·AIM:To evaluate the efficacy and safety of full-thickness sutures combined with intracameral air injection(FTS-AI)versus pre-Descemet’s membrane sutures combined with intracameral air injection(PDS-AI)in the ma...·AIM:To evaluate the efficacy and safety of full-thickness sutures combined with intracameral air injection(FTS-AI)versus pre-Descemet’s membrane sutures combined with intracameral air injection(PDS-AI)in the management of acute corneal hydrops in keratoconus.·METHODS:The research included 8 patients(8 eyes)suffering from acute corneal hydrops caused by keratoconus.Four patients were randomly assigned to FTS-AI.And the other four were randomly assigned to PDS-AI.Corneal oedema,visual acuity,corneal thickness were assessed during follow-up.·RESULTS:The demographics,preoperative duration of symptoms and severity of corneal hydrops between the two groups were not significantly different.The mean corneal oedema resolution time after FTS-AI and PDSAI were 11±1.15 and 15±1.41 d,respectively(P=0.005).The maximum corneal thickness of the scarred region decreased in both groups at one week postoperatively(P<0.05).No obvious difference was found in the mean maximal corneal thickness between the two groups postoperatively.The BCVA improved significantly after FTS-AI and PDS-AI at three months postoperatively.No obvious difference was found in the BCVA after FTS-AI and PDS-AI at three months postoperatively.·CONCLUSION:FTS-AI and PDS-AI are safe and effective therapies to accelerate the resolution of corneal oedema in acute corneal hydrops secondary to keratoconus.Despite faster resolution of corneal oedema in the FTS-AI group,we recommend PDS-AI to avoid potential endothelium cell damage.展开更多
The oil oxidation characteristics of the whole temperature regions from 30 ℃ to 600 ℃ during oil reservoir air injection were revealed by experiments. The whole oil oxidation temperature regions were divided into fo...The oil oxidation characteristics of the whole temperature regions from 30 ℃ to 600 ℃ during oil reservoir air injection were revealed by experiments. The whole oil oxidation temperature regions were divided into four different parts: dissolving and inflation region, low temperature oxidation region, medium temperature oxidation region and high temperature oxidation region. The reaction mechanisms of different regions were explained. Based on the oil oxidation characteristics and filed tests results, light oil reservoirs air injection development methods were divided into two types: oxygen-reducing air flooding and air flooding;heavy oil reservoirs air injection in-situ combustion development methods were divided into two types: medium temperature in-situ combustion and high temperature in-situ combustion. When the reservoir temperature is lower than 120 ℃, oxygen-reducing air flooding should be used for light oil reservoir development. When the reservoir temperature is higher than 120 ℃, air flooding method should be used for light oil reservoir development. For a normal heavy oil reservoir, when the combustion front temperature is lower than 400 ℃, the development method is medium temperature in-situ combustion. For a heavy oil reservoir with high oil resin and asphalting contents, when the combustion front temperature is higher than 450 ℃, the development method at this condition is high temperature in-situ combustion. Ten years field tests of air injection carried out by PetroChina proved that air has advantages in technical, economical and gas source aspects compared with other gas agents for oilfield gas injection development. Air injection development can be used in low/super-low permeability light oil reservoirs, medium and high permeability light oil reservoirs and heavy oil reservoirs. Air is a very promising gas flooding agent.展开更多
Steady air injection upstream of the leading edge was used to increase the surge margin of a centrifugal compressor.To reveal the mechanism,steady numerical simulations were performed on a high pressure ratio centrifu...Steady air injection upstream of the leading edge was used to increase the surge margin of a centrifugal compressor.To reveal the mechanism,steady numerical simulations were performed on a high pressure ratio centrifugal compressor rotor operated with a rotor tip speed of 586 m/s.Eight different injection yaw angle with four different injection mass flow was performed to determine the configuration that provide the best results for the compression system studied in this work.The injection angle,α,was fifteen degree and the injectors were placed at short distance(ten percent of the inlet tip radius upstream of the compressor face) to achieve maximum control over the leading edge flow by varying individual injection parameters.The results show that at design speed(n=50 000 r/min) with injection flow rate more than 2% of the main flow rate and yaw angle between 20° and 30°,the mass flow rate at stall decreases for approximately 8%.But with higher injection rate,other compressor parameters were affected such as compressor efficiency and compressor total pressure ratio.展开更多
From a time value of revenue point of view,it is preferred that the time between reservoir stimulation and oil production response is small.Heavy oil combustion processes have a lag time between air injection and liqu...From a time value of revenue point of view,it is preferred that the time between reservoir stimulation and oil production response is small.Heavy oil combustion processes have a lag time between air injection and liquid production,but the common practice in production data analysis uses simultaneous injection and production data when seeking a relationship between them.In this research,the time scales of production for the Kerrobert toe-to-heel air injection(THAI)heavy oil project in Saskatchewan,Canada,is analyzed by using cross correlation analysis,i.e.time delay analysis between air injection and oil production.The results reveal two time scales with respect to production response with two distinctive recovery mechanisms:(1)a short time scale response(nearly instantaneous)where oil production peaks right after air injection(directly after opening production well)reflecting cold heavy oil production mechanisms,and(2)a longer time scale(of order of 100-300 days)response where peak production occurs associated with the collective phenomena of air injection,heat generating reactions,heat transfer,and finally,heated mobilized heavy oil drainage to the production well.This understanding of the two time scales and associated production mechanisms provides a basis for improving the performance of THAI.展开更多
Cutter-suction dredger transports slurry through pipeline. But the pipeline is easy to be jammed and frayed because of huge resistance, resulting in limited exertion of dredger and high energy consumption. One of the ...Cutter-suction dredger transports slurry through pipeline. But the pipeline is easy to be jammed and frayed because of huge resistance, resulting in limited exertion of dredger and high energy consumption. One of the solutions is air injection transporting, which can reduce the resistance in pipeline. This paper makes research on the relations between pipeline distance and other factors such as slurry concentration, pressure of air injection and transportation distance, by making use of Prof. Aluf Orell' s slug model. The test data prove that the key factors are slurry concentration and air volume fraction, and that high slurry concentration and low air volume fraction can reduce more resistance, and such reducing effect becomes weaker with the increase of transportation distance.展开更多
Cavitation commonly induces performance deterioration and system vibration in many engineering applications.This paper aims to investigate the effects of air injection on cavitation evolution,pressure pulsation and vi...Cavitation commonly induces performance deterioration and system vibration in many engineering applications.This paper aims to investigate the effects of air injection on cavitation evolution,pressure pulsation and vibration in a centrifugal pump with inducer.In this paper,the high-speed camera is used to capture the gas flow pattern and cavitation evolution process in the inducer.The impacts of air injection on the inlet pressure pulsation and vibration are also investigated.The results show that the cavitation development in the inducer undergoes four patterns:incipient cavitation,sheet cavitation,cloud cavitation and super cavitation.During the development of cavitation,the main frequency of the pressure pulsation shifts to lower frequencies,and the amplitude of the vibration increases.In addition,air injection promotes the incipient cavitation but delays the cavitation development.A small amount of air can effectively decrease amplitudes of pressure pulsation and vibration.But as the air content increases,the fluctuations and amplitudes of pressure pulsation and vibration increase.展开更多
A multitracer-gas method was proposed to study the secondary air(SA)mixing along the bed height in a circulating fluidized bed(CFB)using carbon monoxide(CO),oxygen(O_(2)),and carbon dioxide(CO_(2))as tracer gases.Expe...A multitracer-gas method was proposed to study the secondary air(SA)mixing along the bed height in a circulating fluidized bed(CFB)using carbon monoxide(CO),oxygen(O_(2)),and carbon dioxide(CO_(2))as tracer gases.Experiments were carried out on a cold CFB test rig with a cross-section of 0.42 m×0.73 m and a height of 5.50 m.The effects of superficial velocity,SA ratio,bed inventory,and particle diameter on the SA mixing were investigated.The results indicate that there are some differences in the measurement results obtained using different tracer gases,wherein the deviation between CO and CO_(2) ranges from 42%to 66%and that between O_(2) and CO_(2) ranges from 45%to 71%in the lower part of the fluidized bed.However,these differences became less pronounced as the bed height increased.Besides,the high solid concentration and fine particle diameter in the CFB may weaken the difference.The measurement results of different tracer gases show the same trends under the variation of operating parameters.Increasing superficial velocity and SA ratio and decreasing particle diameter result in better mixing of the SA.The effect of bed inventory on SA mixing is not monotonic.展开更多
In this work, we perform a numerical study of a water flow over a stepped spillway. This flow is described by the Reynolds averaged Navier-Stokes equation (RANS) associated with the turbulence k - model. These equat...In this work, we perform a numerical study of a water flow over a stepped spillway. This flow is described by the Reynolds averaged Navier-Stokes equation (RANS) associated with the turbulence k - model. These equations are solved using a commercial software based on the finite volume scheme and an unstructured mesh. The air-water flow was modeled using volume of fluid (VOF) and multiphasic methods. The characteristics of the profile, etc.. We analyze the effects on the flow structure of the flow were investigated including the total pressure, the velocity steps and countermarch inclination, the air injection through the countermarch into the water flow and the dynamics water discharges. Results show that the inclination of the countermarch relative to the vertical and the air injection into the water flow increase the total pressure in the neighbourhood of the steps.展开更多
This paper is the first attempt to evaluate huff-n-puff air injection in a shale oil reservoir using a simulation approach.Recovery mechanisms and physical processes of huff-n-puff air injection in a shale oil reservo...This paper is the first attempt to evaluate huff-n-puff air injection in a shale oil reservoir using a simulation approach.Recovery mechanisms and physical processes of huff-n-puff air injection in a shale oil reservoir are investigated through investigating production performance,thermal behavior,reservoir pressure and fluid saturation features.Air flooding is used as the basic case for a comparative study.The simulation study suggests that thermal drive is the main recovery mechanism for huff-n-puff air injection in the shale oil reservoir,but not for simple air flooding.The synergic recovery mechanism of air flooding in conventional light oil reservoirs can be replicated in shale oil reservoirs by using air huff-npuff injection strategy.Reducing huff-n-puff time is better for performing the synergic recovery mechanism of air injection.O2 diffusion plays an important role in huff-n-puff air injection in shale oil reservoirs.Pressure transmissibility as well as reservoir pressure maintenance ability in huff-n-puff air injection is more pronounced than the simple air flooding after primary depletion stage.No obvious gas override is exhibited in both air flooding and air huff-n-puff injection scenarios in shale reservoirs.Huffn-puff air injection has great potential to develop shale oil reservoirs.The results from this work may stimulate further investigations.展开更多
The aim of this study is to reveal the influence mechanism of endwall air injection with distributed holes on the corner separation of a highly loaded compressor cascade,so as to promote the application of injection i...The aim of this study is to reveal the influence mechanism of endwall air injection with distributed holes on the corner separation of a highly loaded compressor cascade,so as to promote the application of injection in aero-engines.Single-hole and double-hole endwall injection schemes featuring different axial locations,pitchwise locations,injection mass rates and injection directions,were designed and investigated.Results showed that the corner separation was eliminated by endwall injection;the optimal single-hole injection scheme achieved an endwall loss coefficient reduction of 29.7%,with injection coefficient as low as 0.48%.The optimal axial location of single-hole endwall injection was at 82%axial chord,being the center of corner separation.However,as injection hole was located at upstream of it,endwall injection resulted in severer corner separation.The mid-span flow field was deteriorated after endwall injection,which was due to 3D flow effects,i.e.,AVDR(axial velocity density ratio)effect and low-momentum fluid spanwise migration effect.The optimal injection was achieved at low injection angle and from close to the suction surface on pitchwise.Double-hole injection exhibited inferior performance compared with single-hole,which was due to the interaction of the two injection streams and mixing of injection streams with the bulk stream.展开更多
Numerical simulations were performed to model the non-reacting and reacting flow behind a rearward step flameholder in Mach 1.6 supersonic flow with fuel injection at the step base.The combustor geometry was based on ...Numerical simulations were performed to model the non-reacting and reacting flow behind a rearward step flameholder in Mach 1.6 supersonic flow with fuel injection at the step base.The combustor geometry was based on the University of Florida scramjet experimental facility.Turbulence was modeled using k-u shear stress transport(SST),laminar flamelet was used for combustion modeling.Wall static pressure showed good agreement with experimental data for non-reacting and reacting flow.For non-reacting flow,dummy fuel helium mole fraction distribution in the recirculation region behind the step was validated with planar laser induced fluorescence(PLIF)images in experiments.To improve the combustion characteristics,air was injected in tandem with hydrogen at step base using various configurations.With all fuel injection as baseline,the case with 2 air jets around each fuel jet and air injected at 2 times the stagnation pressure of fuel showed the most improvement compared to other cases.It was most effective in reducing the local fuel richness,shortening the flame length and increasing combustion efficiency.展开更多
Air injection is a good option to development light oil reservoir.As well-known that,reservoir heterogeneity has great effect for various EOR processes.This also applies to air injection.However,oil recovery mechanism...Air injection is a good option to development light oil reservoir.As well-known that,reservoir heterogeneity has great effect for various EOR processes.This also applies to air injection.However,oil recovery mechanisms and physical processes for air injection in heterogeneous reservoir with dip angle are still not well understood.The reported setting of reservoir heterogeneous for physical model or simulation model of air injection only simply uses different-layer permeability of porous media.In practice,reservoir heterogeneity follows the principle of geostatistics.How much of contrast in permeability actually challenges the air injection in light oil reservoir?This should be investigated by using layered porous medial settings of the classical Dykstra-Parsons style.Unfortunately,there has been no work addressing this issue for air injection in light oil reservoir.In this paper,Reservoir heterogeneity is quantified based on the use of different reservoir permeability distribution according to classical Dykstra-Parsons coefficients method.The aim of this work is to investigate the effect of reservoir heterogeneity on physical process and production performance of air injection in light oil reservoir through numerical reservoir simulation approach.The basic model is calibrated based on previous study.Total eleven pseudo compounders are included in this model and ten complexity of reactions are proposed to achieve the reaction scheme.Results show that oil recovery factor is decreased with the increasing of reservoir heterogeneity both for air and N2 injection from updip location,which is against the working behavior of air injection from updip location.Reservoir heterogeneity sometimes can act as positive effect to improve sweep efficiency as well as enhance production performance for air injection.High O2 content air injection can benefit oil recovery factor,also lead to early O2 breakthrough in heterogeneous reservoir.Well-type does not show great effect on production performance for air injection in extreme heterogeneous reservoir.While adopting horizontal producer is favourable to promote production performance for air injection in homogenous reservoir.展开更多
Alkaline pretreatment(AL)and air mixing(air)both have the potential to improve anaerobic co-digestion(Co-AD)of poultry litter with wheat straw for methane production.In this study,the effects of the combination of AL(...Alkaline pretreatment(AL)and air mixing(air)both have the potential to improve anaerobic co-digestion(Co-AD)of poultry litter with wheat straw for methane production.In this study,the effects of the combination of AL(pH 12 for 12 h)and air mixing(12 mL·d^(−1))on the Co-AD process were investigated.The substrate hydrolysis was enhanced by AL,with soluble chemical oxygen demand increased by 4.59 times and volatile fatty acids increased by 5.04 times.The cumulative methane yield in the group of Co-AD by AL integrated with air(Co-(AL+air)),being 287 mL·(g VS_(added))^(−1),was improved by 46.7%compared to the control.The cone model was found the best in simulating the methane yield kinetics with R^(2)≥0.9979 and root mean square prediction error(rMSPE)≤3.50.Co-(AL+air)had a larger hydrolysis constant k(0.14 d^(−1))and a shorter lag phaseλ(0.99 d)than the control(k=0.12 d^(−1),λ=2.06 d).The digestate improved the removal of total solids and total volatile solids by 2.0 and 2.3 times,respectively.AL facilitated substrate degradation,while air can enrich the microbial activity,together enhancing the methane generation.The results show that AL+air can be applied as an effective method to improve methane production from the Co-AD process.展开更多
The adaptive feedback control of stability with circumferential inlet distortion has been experimentally investigated in a low-speed,axial compressor.The flat-baffles with different span heights are used to simulate d...The adaptive feedback control of stability with circumferential inlet distortion has been experimentally investigated in a low-speed,axial compressor.The flat-baffles with different span heights are used to simulate different distorted inflow cases.Compared with auto-correlation and root-mean-square analysis,cross-correlation analysis used to predict early stall warning does not depend on the distortion position.Hence,the cross-correlation coefficient was used to monitor the stable status of the compressor and provide the feedback signal in the active control strategy when suffering from different distortions.Based on the stall margin improvement of tip air injection obtained under different distorted inflow cases and the sensitivity analysis of cross-correlation coefficients to injected momentum ratios,tip air injection was adopted as the actuator for adaptive feedback control.The digital signal processing controller was designed and applied to achieve adaptive feedback control in distorted inflow conditions.The results show that the adaptive feedback control of air injection nearly achieves the same stall margin improvement as steady air injection under different distortion intensities with a reduced injection mass flow.Thus,the proposed adaptive feedback control method is ideal for the engine operation with circumferential distorted inflow,which frequently occurs in flight.展开更多
The presence of a bottom water(BW)layer in heavy oil reservoirs can present substantial problems for efficient oil recovery for all recovery techniques.Hence,it is necessary to know how particular production processes...The presence of a bottom water(BW)layer in heavy oil reservoirs can present substantial problems for efficient oil recovery for all recovery techniques.Hence,it is necessary to know how particular production processes are affected by different BW layer thicknesses,and how standard production procedures can be adapted to handle such reservoirs.Toe-to-heel air injection(THAI)is a thermally efficient process,generating in situ energy in the reservoir by burning a fraction of the oil-in-place as coke and has the potential to economically and environmentally friendly work in reservoirs with BW layer.However,to ascertain that,studies are needed first.These are conducted via numerical simulations using commercial reservoir thermal simulator,CMG STARS.This work has shown that the shape of the combustion zone in THAI remains forward-leaning even in the presence of a BW layer,indicating that the process is stable,and that there is no oxygen bypassing of the combustion front.However,the oil recovery rate is highly negatively affected by how large the thickness of the BWzone is,and the severity of such effect is determined to be proportional to the thickness of the BW layer.This study also shows that there is a period of low oil production rate which corresponds to mobilised oil displacement into the BW zone which in turn causes a surge in water production rate.The practical implication of this is that prolonged period of low oil production rates will expose companies and/or investors to higher risk due to the oil market volatility.In this study,it is also revealed that the height of the mobilised oil that is displaced into the BW zone equates to that of the displaced and replaced water thereby implying that when the BW layer thickness is 50%that of the oil layer(OL),less than 50%of the mobilised oil will be recovered when the entire reservoir is swept by the combustion front.Therefore,conclusively,applying the THAI process in its conventional form in reservoirs containing bottom water is not recommended,and as a result,a new strategy is needed to enhance process economics by improving the oil production and hence recovery rates.展开更多
This article experimentally studies the effects of air injection near the blade trailing edge on flow separation and losses in a highly loaded linear compressor cascade. Aerodynamic parameters of eight cascades with d...This article experimentally studies the effects of air injection near the blade trailing edge on flow separation and losses in a highly loaded linear compressor cascade. Aerodynamic parameters of eight cascades with different air injection slot configura- tions are measured by using a five-hole probe at the cascade outlets. Ink-trace flow visualization is performed to obtain the flow details around the air injection slots. The static pressure distribution is clarified with pressure taps on the endwalls. The...展开更多
This paper introduces a novel design method of highly loaded compressor blades with air injection.CFD methods were firstly validated with existing data and then used to develop and investigate the new method based on ...This paper introduces a novel design method of highly loaded compressor blades with air injection.CFD methods were firstly validated with existing data and then used to develop and investigate the new method based on a compressor cascade.A compressor blade is designed with a curvature induced pressure-recovery concept.A rapid drop of the local curvature on the blade suction surface results in a sudden increase in the local pressure,which is referred to as a curvature induced ‘Shock'.An injection slot downstream from the ‘Shock' is used to prevent ‘Shock' induced separation,thus reducing the loss.As a result,the compressor blade achieves high loading with acceptable loss.First,the design concept based on a 2D compressor blade profile is introduced.Then,a 3D cascade model is investigated with uniform air injection along the span.The effects of the incidence are also investigated on emphasis in the current study.The mid-span flow field of the 3D injected cascade shows excellent agreement with the 2D designed flow field.For the highly loaded cascade without injection,the flow separates immediately downstream from the ‘Shock';the initial location of separation shows little change in a large incidence range.Thus air injection with the same injection configuration effectively removes the flow separation downstream from the curvature induced ‘Shock' and reduces the size of the separation zone at different incidences.Near the endwall,the flow within the incoming passage vortex mixes with the injected flow.As a result,the size of the passage vortex reduces significantly downstream from the injection slot.After air injection,the loss coefficient along spanwise reduces significantly and the flow turning angle increases.展开更多
According to the analysis of the 2020 estimates of the International Energy Agency(2020),the world will require up to 770 billion barrels of oil from now to 2040.However,based on the British Petroleum(BP)statistical r...According to the analysis of the 2020 estimates of the International Energy Agency(2020),the world will require up to 770 billion barrels of oil from now to 2040.However,based on the British Petroleum(BP)statistical review of world energy 2020,the world-wide total reserve of the conventional light oil is only 520.2 billion barrels as at the end of 2019.That implies that the remaining 249.8 billion barrels of oil urgently needed to ensure a smooth transition to a decarbonised global energy and economic systems is provided must come from unconventional oils(i.e.heavy oils and bitumen)reserves.But heavy oils and bitumen are very difficult to produce and the current commercial production technologies have poor efficiency and release large quantities of greenhouse gases.Therefore,these resources should ideally be upgraded and produced using technologies that have greener credentials.This is where the energy-efficient,environmentally friendly,and self-sustaining THAI-CAPRI coupled in situ combustion and in situ catalytic upgrading process comes in.However,the novel THAI-CAPRI process is trialled only once at field and it has not gained wide recognition due to poor understanding of the optimal design parameters and procedures.Hence,this work reports the first ever results of investigations of the effect of operating pressure on the performance of the THAI-CAPRI process.Two experimental scale numerical models of the process based on Athabasca tar sand properties were run at pressures of 8000 kPa and 500 kPa respectively using CMG STARS.This study has shown that the higher the operating pressure,the larger the API gravity and the higher the cumulative volume of high-quality oil is produced(i.e.a 2300 cm3 of z24 oAPI oil produced at 8000 kPa versus the 2050 cm3 of z17.5 oAPI oil produced at 500 kPa).The study has further shown that despite presence of annular catalyst layer,the THAI-CAPRI process operates stably.However,it is found that a more stable and safer operation of the process can only be achieved at optimal pressure that should lie between 500 kPa and 8000 kPa,especially since at the lower pressure,should the process time be extended,it will not take long before oxygen breakthrough takes place.The simulations have shown in details that at higher pressures,the catalyst bed is easily and rapidly coked and thus the catalyst life will be very short especially during actual field reservoir operations.Since the oil drainage flux into the HP well at field-scale is different from that at laboratory-scale,and at field-scale,the combustion front does not propagate inside the HP well,it will be practically very challenging to regenerate or replace the coke-deactivated annular catalyst layer in actual reservoir operations.There-fore,it is concluded that during field operation designs,an optimum pressure must be selected such that a balance is obtained between the combustion front stability and the degree of catalytic upgrading,and between the catalyst life and its effectiveness.展开更多
Based on the analysis of recent projections by the International Energy Agency(IEA),to meet the growing and subsequently declining demands of oil from now to 2040,we need up to around 770 billion barrels of oil.Since ...Based on the analysis of recent projections by the International Energy Agency(IEA),to meet the growing and subsequently declining demands of oil from now to 2040,we need up to around 770 billion barrels of oil.Since the worldwide total proved reserves of easy-and-cheaper-to-produce conventional oils is roughly only 520.2 billion barrels,the remaining 249.8 billion barrels must be obtained from unconventional petroleum resources(i.e.heavy oils and bitumen).These resources are however very difficult and costly to upgrade and produce due to their inherently high asphaltene contents which are reflected in their very high viscosities and large densities.However,still they should prove attractive development prospects if,as much as practicably possible,their upgrading can be performed in conjunction with in situ or downhole catalytic upgrading processes.Such projects will contribute significantly towards smoother and greener transition to full decarbonisation.Advanced technologies,such as the toe-to-heel air injection coupled to its add-on in situ catalytic process(i.e.THAI-CAPRI processes),have the potential to develop these reserves,but require further developmental understanding to realise their full capability.In this work,a new detailed procedure for numerically simulating the THAI-CAPRI processes is presented.The numerical model is made-up of Athabasca-type bitumen and it has a horizontal producer(HP)well that is surrounded by an annular layer of alumina-supported cobalt-oxide-molybdenum-oxide(CoMo/γ-Al2O3)catalyst.The simulation is performed using the computer modelling group(CMG)reservoir simulator,STARS.This new work has shown that the choice of the frequency factor of the catalytic reactions allowed model validation based on the degree of catalytic upgrading in form of API gravity.Overall,the work herein identifies the important parameters,such as API gravity,peak temperature,oil production rate,cumulative oil production,produced oxygen concentration,temperature distribution profile,extent of coke deposition on the catalyst surface,etc.,governing the successful operation of the THAI-CAPRI processes.In particular,this study has shown that even in the vicinities of the mobile oil zone(MOZ)where the catalytic upgrading is expected to be taking place,the catalyst surfaces are covered with high concentration of coke.This finding is in parallel to the observations reported from experiment of CAPRI process alone.Therefore,it is concluded that when experimental studies of the THAI-CAPRI processes are to be conducted,a catalyst regeneration mechanism must be put in place in order to prolong the effectiveness and thus the life of the catalyst so that proper field operation design can be made.Additionally,the study has also shown that the temperature of the MOZ is less than 306°C and that implies that an external source of heating the annular catalyst layer must be provided in order to effect the catalytic upgrading in the THAI-CAPRI processes.Thus,a new study should look at the feasibility of targeted heating(in the case of microwave)or conductive or resistive heating(in the case of electrical heating)to raise the temperature of the annular catalyst layer to that required to achieve the catalytic upgrading.展开更多
基金Supported by the National Natural Science Foundation of China(No.82070920)Major Clinical Research Projects of the Three-Year Action Plan for Promoting Clinical Skills and Clinical Innovation in Municipal Hospitals(No.SHDC2020CR1043B-010)。
文摘·AIM:To evaluate the efficacy and safety of full-thickness sutures combined with intracameral air injection(FTS-AI)versus pre-Descemet’s membrane sutures combined with intracameral air injection(PDS-AI)in the management of acute corneal hydrops in keratoconus.·METHODS:The research included 8 patients(8 eyes)suffering from acute corneal hydrops caused by keratoconus.Four patients were randomly assigned to FTS-AI.And the other four were randomly assigned to PDS-AI.Corneal oedema,visual acuity,corneal thickness were assessed during follow-up.·RESULTS:The demographics,preoperative duration of symptoms and severity of corneal hydrops between the two groups were not significantly different.The mean corneal oedema resolution time after FTS-AI and PDSAI were 11±1.15 and 15±1.41 d,respectively(P=0.005).The maximum corneal thickness of the scarred region decreased in both groups at one week postoperatively(P<0.05).No obvious difference was found in the mean maximal corneal thickness between the two groups postoperatively.The BCVA improved significantly after FTS-AI and PDS-AI at three months postoperatively.No obvious difference was found in the BCVA after FTS-AI and PDS-AI at three months postoperatively.·CONCLUSION:FTS-AI and PDS-AI are safe and effective therapies to accelerate the resolution of corneal oedema in acute corneal hydrops secondary to keratoconus.Despite faster resolution of corneal oedema in the FTS-AI group,we recommend PDS-AI to avoid potential endothelium cell damage.
文摘The oil oxidation characteristics of the whole temperature regions from 30 ℃ to 600 ℃ during oil reservoir air injection were revealed by experiments. The whole oil oxidation temperature regions were divided into four different parts: dissolving and inflation region, low temperature oxidation region, medium temperature oxidation region and high temperature oxidation region. The reaction mechanisms of different regions were explained. Based on the oil oxidation characteristics and filed tests results, light oil reservoirs air injection development methods were divided into two types: oxygen-reducing air flooding and air flooding;heavy oil reservoirs air injection in-situ combustion development methods were divided into two types: medium temperature in-situ combustion and high temperature in-situ combustion. When the reservoir temperature is lower than 120 ℃, oxygen-reducing air flooding should be used for light oil reservoir development. When the reservoir temperature is higher than 120 ℃, air flooding method should be used for light oil reservoir development. For a normal heavy oil reservoir, when the combustion front temperature is lower than 400 ℃, the development method is medium temperature in-situ combustion. For a heavy oil reservoir with high oil resin and asphalting contents, when the combustion front temperature is higher than 450 ℃, the development method at this condition is high temperature in-situ combustion. Ten years field tests of air injection carried out by PetroChina proved that air has advantages in technical, economical and gas source aspects compared with other gas agents for oilfield gas injection development. Air injection development can be used in low/super-low permeability light oil reservoirs, medium and high permeability light oil reservoirs and heavy oil reservoirs. Air is a very promising gas flooding agent.
基金Supported by Chinese Specialized Research Fund for the Doctoral Program of Higher Education (20091101110014)the National Natural Science Foundation of China (51176013)National High Technology Research and Development Program of China("863" Program) (2007AA050502)
文摘Steady air injection upstream of the leading edge was used to increase the surge margin of a centrifugal compressor.To reveal the mechanism,steady numerical simulations were performed on a high pressure ratio centrifugal compressor rotor operated with a rotor tip speed of 586 m/s.Eight different injection yaw angle with four different injection mass flow was performed to determine the configuration that provide the best results for the compression system studied in this work.The injection angle,α,was fifteen degree and the injectors were placed at short distance(ten percent of the inlet tip radius upstream of the compressor face) to achieve maximum control over the leading edge flow by varying individual injection parameters.The results show that at design speed(n=50 000 r/min) with injection flow rate more than 2% of the main flow rate and yaw angle between 20° and 30°,the mass flow rate at stall decreases for approximately 8%.But with higher injection rate,other compressor parameters were affected such as compressor efficiency and compressor total pressure ratio.
基金support from the Department of Chemical and Petroleum Engineering at the University of Calgary,the University of Calgary’s Canada First Research Excellence Fund program(the Global Research Initiative for Sustainable Low-Carbon Unconventional Resources)
文摘From a time value of revenue point of view,it is preferred that the time between reservoir stimulation and oil production response is small.Heavy oil combustion processes have a lag time between air injection and liquid production,but the common practice in production data analysis uses simultaneous injection and production data when seeking a relationship between them.In this research,the time scales of production for the Kerrobert toe-to-heel air injection(THAI)heavy oil project in Saskatchewan,Canada,is analyzed by using cross correlation analysis,i.e.time delay analysis between air injection and oil production.The results reveal two time scales with respect to production response with two distinctive recovery mechanisms:(1)a short time scale response(nearly instantaneous)where oil production peaks right after air injection(directly after opening production well)reflecting cold heavy oil production mechanisms,and(2)a longer time scale(of order of 100-300 days)response where peak production occurs associated with the collective phenomena of air injection,heat generating reactions,heat transfer,and finally,heated mobilized heavy oil drainage to the production well.This understanding of the two time scales and associated production mechanisms provides a basis for improving the performance of THAI.
文摘Cutter-suction dredger transports slurry through pipeline. But the pipeline is easy to be jammed and frayed because of huge resistance, resulting in limited exertion of dredger and high energy consumption. One of the solutions is air injection transporting, which can reduce the resistance in pipeline. This paper makes research on the relations between pipeline distance and other factors such as slurry concentration, pressure of air injection and transportation distance, by making use of Prof. Aluf Orell' s slug model. The test data prove that the key factors are slurry concentration and air volume fraction, and that high slurry concentration and low air volume fraction can reduce more resistance, and such reducing effect becomes weaker with the increase of transportation distance.
基金supported by the National Natural Science Foundation of China(Grant No.51979126).
文摘Cavitation commonly induces performance deterioration and system vibration in many engineering applications.This paper aims to investigate the effects of air injection on cavitation evolution,pressure pulsation and vibration in a centrifugal pump with inducer.In this paper,the high-speed camera is used to capture the gas flow pattern and cavitation evolution process in the inducer.The impacts of air injection on the inlet pressure pulsation and vibration are also investigated.The results show that the cavitation development in the inducer undergoes four patterns:incipient cavitation,sheet cavitation,cloud cavitation and super cavitation.During the development of cavitation,the main frequency of the pressure pulsation shifts to lower frequencies,and the amplitude of the vibration increases.In addition,air injection promotes the incipient cavitation but delays the cavitation development.A small amount of air can effectively decrease amplitudes of pressure pulsation and vibration.But as the air content increases,the fluctuations and amplitudes of pressure pulsation and vibration increase.
基金the Key Project of the National Research Program of China(2020YFB0606201)。
文摘A multitracer-gas method was proposed to study the secondary air(SA)mixing along the bed height in a circulating fluidized bed(CFB)using carbon monoxide(CO),oxygen(O_(2)),and carbon dioxide(CO_(2))as tracer gases.Experiments were carried out on a cold CFB test rig with a cross-section of 0.42 m×0.73 m and a height of 5.50 m.The effects of superficial velocity,SA ratio,bed inventory,and particle diameter on the SA mixing were investigated.The results indicate that there are some differences in the measurement results obtained using different tracer gases,wherein the deviation between CO and CO_(2) ranges from 42%to 66%and that between O_(2) and CO_(2) ranges from 45%to 71%in the lower part of the fluidized bed.However,these differences became less pronounced as the bed height increased.Besides,the high solid concentration and fine particle diameter in the CFB may weaken the difference.The measurement results of different tracer gases show the same trends under the variation of operating parameters.Increasing superficial velocity and SA ratio and decreasing particle diameter result in better mixing of the SA.The effect of bed inventory on SA mixing is not monotonic.
基金the ERASMUS MUNDUS AVERROES Program,for the financial support off this study
文摘In this work, we perform a numerical study of a water flow over a stepped spillway. This flow is described by the Reynolds averaged Navier-Stokes equation (RANS) associated with the turbulence k - model. These equations are solved using a commercial software based on the finite volume scheme and an unstructured mesh. The air-water flow was modeled using volume of fluid (VOF) and multiphasic methods. The characteristics of the profile, etc.. We analyze the effects on the flow structure of the flow were investigated including the total pressure, the velocity steps and countermarch inclination, the air injection through the countermarch into the water flow and the dynamics water discharges. Results show that the inclination of the countermarch relative to the vertical and the air injection into the water flow increase the total pressure in the neighbourhood of the steps.
基金The authors would like to acknowledge the funding from U.S.Department of Energy under Award Number DE-FE0024311In addition,this paper was supported by National Natural Science Foundation of China(No.51404202)+1 种基金Sichuan Youth Science and Technology Fund(No.2015JQ0038)scientific research starting project of SWPU(No.2014QHZ001).
文摘This paper is the first attempt to evaluate huff-n-puff air injection in a shale oil reservoir using a simulation approach.Recovery mechanisms and physical processes of huff-n-puff air injection in a shale oil reservoir are investigated through investigating production performance,thermal behavior,reservoir pressure and fluid saturation features.Air flooding is used as the basic case for a comparative study.The simulation study suggests that thermal drive is the main recovery mechanism for huff-n-puff air injection in the shale oil reservoir,but not for simple air flooding.The synergic recovery mechanism of air flooding in conventional light oil reservoirs can be replicated in shale oil reservoirs by using air huff-npuff injection strategy.Reducing huff-n-puff time is better for performing the synergic recovery mechanism of air injection.O2 diffusion plays an important role in huff-n-puff air injection in shale oil reservoirs.Pressure transmissibility as well as reservoir pressure maintenance ability in huff-n-puff air injection is more pronounced than the simple air flooding after primary depletion stage.No obvious gas override is exhibited in both air flooding and air huff-n-puff injection scenarios in shale reservoirs.Huffn-puff air injection has great potential to develop shale oil reservoirs.The results from this work may stimulate further investigations.
基金This work was sponsored by the seed Foundation of Innovation and Creation for Graduate Students in Northwestern Polytechnical University(No.CX2020138)National Natural Science Foundation of China(Nos.51806174 and 51741601)the Fundamental Research Funds for the Central Universities of China(No.G2018KY0303).
文摘The aim of this study is to reveal the influence mechanism of endwall air injection with distributed holes on the corner separation of a highly loaded compressor cascade,so as to promote the application of injection in aero-engines.Single-hole and double-hole endwall injection schemes featuring different axial locations,pitchwise locations,injection mass rates and injection directions,were designed and investigated.Results showed that the corner separation was eliminated by endwall injection;the optimal single-hole injection scheme achieved an endwall loss coefficient reduction of 29.7%,with injection coefficient as low as 0.48%.The optimal axial location of single-hole endwall injection was at 82%axial chord,being the center of corner separation.However,as injection hole was located at upstream of it,endwall injection resulted in severer corner separation.The mid-span flow field was deteriorated after endwall injection,which was due to 3D flow effects,i.e.,AVDR(axial velocity density ratio)effect and low-momentum fluid spanwise migration effect.The optimal injection was achieved at low injection angle and from close to the suction surface on pitchwise.Double-hole injection exhibited inferior performance compared with single-hole,which was due to the interaction of the two injection streams and mixing of injection streams with the bulk stream.
文摘Numerical simulations were performed to model the non-reacting and reacting flow behind a rearward step flameholder in Mach 1.6 supersonic flow with fuel injection at the step base.The combustor geometry was based on the University of Florida scramjet experimental facility.Turbulence was modeled using k-u shear stress transport(SST),laminar flamelet was used for combustion modeling.Wall static pressure showed good agreement with experimental data for non-reacting and reacting flow.For non-reacting flow,dummy fuel helium mole fraction distribution in the recirculation region behind the step was validated with planar laser induced fluorescence(PLIF)images in experiments.To improve the combustion characteristics,air was injected in tandem with hydrogen at step base using various configurations.With all fuel injection as baseline,the case with 2 air jets around each fuel jet and air injected at 2 times the stagnation pressure of fuel showed the most improvement compared to other cases.It was most effective in reducing the local fuel richness,shortening the flame length and increasing combustion efficiency.
基金This work is supported by the fund of National Science Foundation of China(Award No.51404202)Sichuan Youth Science and Technology Fund(Award No.2015JQ0038)PetroChina Innovation Foundation(Award No.2017D-5007-0202).
文摘Air injection is a good option to development light oil reservoir.As well-known that,reservoir heterogeneity has great effect for various EOR processes.This also applies to air injection.However,oil recovery mechanisms and physical processes for air injection in heterogeneous reservoir with dip angle are still not well understood.The reported setting of reservoir heterogeneous for physical model or simulation model of air injection only simply uses different-layer permeability of porous media.In practice,reservoir heterogeneity follows the principle of geostatistics.How much of contrast in permeability actually challenges the air injection in light oil reservoir?This should be investigated by using layered porous medial settings of the classical Dykstra-Parsons style.Unfortunately,there has been no work addressing this issue for air injection in light oil reservoir.In this paper,Reservoir heterogeneity is quantified based on the use of different reservoir permeability distribution according to classical Dykstra-Parsons coefficients method.The aim of this work is to investigate the effect of reservoir heterogeneity on physical process and production performance of air injection in light oil reservoir through numerical reservoir simulation approach.The basic model is calibrated based on previous study.Total eleven pseudo compounders are included in this model and ten complexity of reactions are proposed to achieve the reaction scheme.Results show that oil recovery factor is decreased with the increasing of reservoir heterogeneity both for air and N2 injection from updip location,which is against the working behavior of air injection from updip location.Reservoir heterogeneity sometimes can act as positive effect to improve sweep efficiency as well as enhance production performance for air injection.High O2 content air injection can benefit oil recovery factor,also lead to early O2 breakthrough in heterogeneous reservoir.Well-type does not show great effect on production performance for air injection in extreme heterogeneous reservoir.While adopting horizontal producer is favourable to promote production performance for air injection in homogenous reservoir.
基金funded by USDA/NIFA/AFRI Applied Science and Foundational Program(2019-67021-29945)the authors want to show appreciation for the financial support provided by the United States Department of Agriculture.
文摘Alkaline pretreatment(AL)and air mixing(air)both have the potential to improve anaerobic co-digestion(Co-AD)of poultry litter with wheat straw for methane production.In this study,the effects of the combination of AL(pH 12 for 12 h)and air mixing(12 mL·d^(−1))on the Co-AD process were investigated.The substrate hydrolysis was enhanced by AL,with soluble chemical oxygen demand increased by 4.59 times and volatile fatty acids increased by 5.04 times.The cumulative methane yield in the group of Co-AD by AL integrated with air(Co-(AL+air)),being 287 mL·(g VS_(added))^(−1),was improved by 46.7%compared to the control.The cone model was found the best in simulating the methane yield kinetics with R^(2)≥0.9979 and root mean square prediction error(rMSPE)≤3.50.Co-(AL+air)had a larger hydrolysis constant k(0.14 d^(−1))and a shorter lag phaseλ(0.99 d)than the control(k=0.12 d^(−1),λ=2.06 d).The digestate improved the removal of total solids and total volatile solids by 2.0 and 2.3 times,respectively.AL facilitated substrate degradation,while air can enrich the microbial activity,together enhancing the methane generation.The results show that AL+air can be applied as an effective method to improve methane production from the Co-AD process.
基金co-supported by the National Natural Science Foundation of China(No.51922098)the National Science and Technology Major Project of China(No.2017-Ⅱ-0004-0017)the Special Fund for the Member of Youth Innovation Promotion Association of CAS(No.2018173).
文摘The adaptive feedback control of stability with circumferential inlet distortion has been experimentally investigated in a low-speed,axial compressor.The flat-baffles with different span heights are used to simulate different distorted inflow cases.Compared with auto-correlation and root-mean-square analysis,cross-correlation analysis used to predict early stall warning does not depend on the distortion position.Hence,the cross-correlation coefficient was used to monitor the stable status of the compressor and provide the feedback signal in the active control strategy when suffering from different distortions.Based on the stall margin improvement of tip air injection obtained under different distorted inflow cases and the sensitivity analysis of cross-correlation coefficients to injected momentum ratios,tip air injection was adopted as the actuator for adaptive feedback control.The digital signal processing controller was designed and applied to achieve adaptive feedback control in distorted inflow conditions.The results show that the adaptive feedback control of air injection nearly achieves the same stall margin improvement as steady air injection under different distortion intensities with a reduced injection mass flow.Thus,the proposed adaptive feedback control method is ideal for the engine operation with circumferential distorted inflow,which frequently occurs in flight.
文摘The presence of a bottom water(BW)layer in heavy oil reservoirs can present substantial problems for efficient oil recovery for all recovery techniques.Hence,it is necessary to know how particular production processes are affected by different BW layer thicknesses,and how standard production procedures can be adapted to handle such reservoirs.Toe-to-heel air injection(THAI)is a thermally efficient process,generating in situ energy in the reservoir by burning a fraction of the oil-in-place as coke and has the potential to economically and environmentally friendly work in reservoirs with BW layer.However,to ascertain that,studies are needed first.These are conducted via numerical simulations using commercial reservoir thermal simulator,CMG STARS.This work has shown that the shape of the combustion zone in THAI remains forward-leaning even in the presence of a BW layer,indicating that the process is stable,and that there is no oxygen bypassing of the combustion front.However,the oil recovery rate is highly negatively affected by how large the thickness of the BWzone is,and the severity of such effect is determined to be proportional to the thickness of the BW layer.This study also shows that there is a period of low oil production rate which corresponds to mobilised oil displacement into the BW zone which in turn causes a surge in water production rate.The practical implication of this is that prolonged period of low oil production rates will expose companies and/or investors to higher risk due to the oil market volatility.In this study,it is also revealed that the height of the mobilised oil that is displaced into the BW zone equates to that of the displaced and replaced water thereby implying that when the BW layer thickness is 50%that of the oil layer(OL),less than 50%of the mobilised oil will be recovered when the entire reservoir is swept by the combustion front.Therefore,conclusively,applying the THAI process in its conventional form in reservoirs containing bottom water is not recommended,and as a result,a new strategy is needed to enhance process economics by improving the oil production and hence recovery rates.
基金National Natural Science Foundation of China (50876023)Chinese Specialized Research Fund for the Doctoral Pro-gram of Higher Education (20060213007)National Basic Research Program of China (2007CB210100)
文摘This article experimentally studies the effects of air injection near the blade trailing edge on flow separation and losses in a highly loaded linear compressor cascade. Aerodynamic parameters of eight cascades with different air injection slot configura- tions are measured by using a five-hole probe at the cascade outlets. Ink-trace flow visualization is performed to obtain the flow details around the air injection slots. The static pressure distribution is clarified with pressure taps on the endwalls. The...
基金co-supported by the National Natural Science Foundation of China(Nos.51576003 and 11521091)China Postdoctoral Science Foundation(No.2016M600015)
文摘This paper introduces a novel design method of highly loaded compressor blades with air injection.CFD methods were firstly validated with existing data and then used to develop and investigate the new method based on a compressor cascade.A compressor blade is designed with a curvature induced pressure-recovery concept.A rapid drop of the local curvature on the blade suction surface results in a sudden increase in the local pressure,which is referred to as a curvature induced ‘Shock'.An injection slot downstream from the ‘Shock' is used to prevent ‘Shock' induced separation,thus reducing the loss.As a result,the compressor blade achieves high loading with acceptable loss.First,the design concept based on a 2D compressor blade profile is introduced.Then,a 3D cascade model is investigated with uniform air injection along the span.The effects of the incidence are also investigated on emphasis in the current study.The mid-span flow field of the 3D injected cascade shows excellent agreement with the 2D designed flow field.For the highly loaded cascade without injection,the flow separates immediately downstream from the ‘Shock';the initial location of separation shows little change in a large incidence range.Thus air injection with the same injection configuration effectively removes the flow separation downstream from the curvature induced ‘Shock' and reduces the size of the separation zone at different incidences.Near the endwall,the flow within the incoming passage vortex mixes with the injected flow.As a result,the size of the passage vortex reduces significantly downstream from the injection slot.After air injection,the loss coefficient along spanwise reduces significantly and the flow turning angle increases.
文摘According to the analysis of the 2020 estimates of the International Energy Agency(2020),the world will require up to 770 billion barrels of oil from now to 2040.However,based on the British Petroleum(BP)statistical review of world energy 2020,the world-wide total reserve of the conventional light oil is only 520.2 billion barrels as at the end of 2019.That implies that the remaining 249.8 billion barrels of oil urgently needed to ensure a smooth transition to a decarbonised global energy and economic systems is provided must come from unconventional oils(i.e.heavy oils and bitumen)reserves.But heavy oils and bitumen are very difficult to produce and the current commercial production technologies have poor efficiency and release large quantities of greenhouse gases.Therefore,these resources should ideally be upgraded and produced using technologies that have greener credentials.This is where the energy-efficient,environmentally friendly,and self-sustaining THAI-CAPRI coupled in situ combustion and in situ catalytic upgrading process comes in.However,the novel THAI-CAPRI process is trialled only once at field and it has not gained wide recognition due to poor understanding of the optimal design parameters and procedures.Hence,this work reports the first ever results of investigations of the effect of operating pressure on the performance of the THAI-CAPRI process.Two experimental scale numerical models of the process based on Athabasca tar sand properties were run at pressures of 8000 kPa and 500 kPa respectively using CMG STARS.This study has shown that the higher the operating pressure,the larger the API gravity and the higher the cumulative volume of high-quality oil is produced(i.e.a 2300 cm3 of z24 oAPI oil produced at 8000 kPa versus the 2050 cm3 of z17.5 oAPI oil produced at 500 kPa).The study has further shown that despite presence of annular catalyst layer,the THAI-CAPRI process operates stably.However,it is found that a more stable and safer operation of the process can only be achieved at optimal pressure that should lie between 500 kPa and 8000 kPa,especially since at the lower pressure,should the process time be extended,it will not take long before oxygen breakthrough takes place.The simulations have shown in details that at higher pressures,the catalyst bed is easily and rapidly coked and thus the catalyst life will be very short especially during actual field reservoir operations.Since the oil drainage flux into the HP well at field-scale is different from that at laboratory-scale,and at field-scale,the combustion front does not propagate inside the HP well,it will be practically very challenging to regenerate or replace the coke-deactivated annular catalyst layer in actual reservoir operations.There-fore,it is concluded that during field operation designs,an optimum pressure must be selected such that a balance is obtained between the combustion front stability and the degree of catalytic upgrading,and between the catalyst life and its effectiveness.
文摘Based on the analysis of recent projections by the International Energy Agency(IEA),to meet the growing and subsequently declining demands of oil from now to 2040,we need up to around 770 billion barrels of oil.Since the worldwide total proved reserves of easy-and-cheaper-to-produce conventional oils is roughly only 520.2 billion barrels,the remaining 249.8 billion barrels must be obtained from unconventional petroleum resources(i.e.heavy oils and bitumen).These resources are however very difficult and costly to upgrade and produce due to their inherently high asphaltene contents which are reflected in their very high viscosities and large densities.However,still they should prove attractive development prospects if,as much as practicably possible,their upgrading can be performed in conjunction with in situ or downhole catalytic upgrading processes.Such projects will contribute significantly towards smoother and greener transition to full decarbonisation.Advanced technologies,such as the toe-to-heel air injection coupled to its add-on in situ catalytic process(i.e.THAI-CAPRI processes),have the potential to develop these reserves,but require further developmental understanding to realise their full capability.In this work,a new detailed procedure for numerically simulating the THAI-CAPRI processes is presented.The numerical model is made-up of Athabasca-type bitumen and it has a horizontal producer(HP)well that is surrounded by an annular layer of alumina-supported cobalt-oxide-molybdenum-oxide(CoMo/γ-Al2O3)catalyst.The simulation is performed using the computer modelling group(CMG)reservoir simulator,STARS.This new work has shown that the choice of the frequency factor of the catalytic reactions allowed model validation based on the degree of catalytic upgrading in form of API gravity.Overall,the work herein identifies the important parameters,such as API gravity,peak temperature,oil production rate,cumulative oil production,produced oxygen concentration,temperature distribution profile,extent of coke deposition on the catalyst surface,etc.,governing the successful operation of the THAI-CAPRI processes.In particular,this study has shown that even in the vicinities of the mobile oil zone(MOZ)where the catalytic upgrading is expected to be taking place,the catalyst surfaces are covered with high concentration of coke.This finding is in parallel to the observations reported from experiment of CAPRI process alone.Therefore,it is concluded that when experimental studies of the THAI-CAPRI processes are to be conducted,a catalyst regeneration mechanism must be put in place in order to prolong the effectiveness and thus the life of the catalyst so that proper field operation design can be made.Additionally,the study has also shown that the temperature of the MOZ is less than 306°C and that implies that an external source of heating the annular catalyst layer must be provided in order to effect the catalytic upgrading in the THAI-CAPRI processes.Thus,a new study should look at the feasibility of targeted heating(in the case of microwave)or conductive or resistive heating(in the case of electrical heating)to raise the temperature of the annular catalyst layer to that required to achieve the catalytic upgrading.