Study on Sealing Characteristics of Sliding Seal Assembly of Aircraft Hydraulic Actuator

The hydraulic actuator,known as the"muscle"of military aircraft,is responsible for flight attitude adjustment,trajectory control,braking turn,landing gear retracting and other actions,which directly affect its flight efficiency and safety.However,the sealing assembly often has the situation of over-aberrant aperture fit clearance or critical over-aberrant clearance,which increases the failure probability and degree of movable seal failure,and directly affects the flight efficiency and safety of military aircraft.In this paper,the simulation model of hydraulic actuator seal combination is established by ANSYS software,and the sealing principle is described.The change curve of contact width and contact pressure of combination seal under the action of high-pressure fluid is drawn.The effects of different oil pressure,fit clearance and other parameters on the sealing performance are analyzed.Finally,the accelerated life test of sliding seal components is carried out on the hydraulic actuator accelerated life test rig,and the surface morphology is compared and analyzed.The research shows that the O-ring is the main sealing element and the role of the check ring is to protect and support the O-ring to prevent damage caused by squeezing into the fit clearance,so the check ring bears a large load and is prone to shear failure.Excessive fit clearance is the main factor affecting the damage of the check ring,and the damage parts are mainly concentrated at the edge of the sealing surface.This paper provides a theoretical basis for the design of hydraulic actuator and the improvement of sealing performance.

Influence of pressure disturbance wave on dynamic response characteristics of liquid film seal for multiphase pump

Slug flow or high GVF(Gas Volume Fraction)conditions can cause pressure disturbance waves and alternating loads at the boundary of mechanical seals for multiphase pumps,endangering the safety of multiphase pump units.The mechanical seal model is simplified by using periodic boundary conditions and numerical calculations are carried out based on the Zwart-Gerber-Belamri cavitation model.UDF(User Define Function)programs such as structural dynamics equations,alternating load equations,and pressure disturbance equations are embedded in numerical calculations,and the dynamic response characteristics of mechanical seal are studied using layered dynamic mesh technology.The results show that when the pressure disturbance occurs at the inlet,as the amplitude and period of the disturbance increase,the film thickness gradually decreases.And the fundamental reason for the hysteresis of the film thickness change is that the pressure in the high-pressure area cannot be restored in a timely manner.The maximum value of leakage and the minimum value of axial velocity are independent of the disturbance period and determined by the disturbance amplitude.The mutual interference between enhanced waves does not have a significant impact on the film thickness,while the front wave in the attenuated wave has a promoting effect on the subsequent film thickness changes,and the fluctuation of the liquid film cavitation rate and axial velocity under the attenuated wave condition deviates from the initial values.Compared with pressure disturbance conditions,alternating load conditions have a more significant impact on film thickness and leakage.During actual operation,it is necessary to avoid alternating load conditions in multiphase pump mechanical seals.

Vegetation characteristics and soil properties of artificially remediated grasslands:The case study of the Shimenhe mining area in Qilian Mountains,northwest China

The mining of limestone mines plays a crucial role in societal and economic advancement.However,mining activities have led to destructive variations in grassland ecology and soil,causing numerous environmental problems,and effective artificial restoration measures have been used to restore grasslands in the Shimenhe mining areas to different degrees.In this study,we investigated,examined and analyzed plant community structure and its correlation with soil properties across varying degrees of alpine grassland restoration in Qilian Mountains Shimenhe restoration mines using the sample method,and studied the changes in species diversity using five diversity indexes(Simpson index,Shannon index,Margalef index,Dominance index and Evenness index).This study showed that the plant community characteristics with high recovered degree(HRD)>middle recovered degree(MRD)>low recovered degree(LRD)>very low recovered degree(VLRD),11 plant genera comprising 11 species across 10 families were identified.Dominant families with robust ecological adaptability included Leguminosae,Rosaceae,Gramineae,Asteraceae,and Salicaceae.The highest Simpson,Shannon,Margalef and Evenness index of HRD grassland community species were 0.82,1.96,1.66 and 0.89,respectively.The highest Dominance index of VLRD grassland community species was 0.34,which required several restoration methods such as spraying and mulching.Soil pH and EC tended to decrease with increasing restoration,SOC,SMC,TP,AP,NH4-N,TN,AN and NO3-N tended to increase and the content of soil environmental factors contributed to vegetation growth across various restoration levels the mine grassland.In conclusion,our study indicated that the community structure gradually diversified and soil properties changed positively with the increase of restoration degrees in the Qilian Mountains Shimenhe mine,and the best results of HRD restoration were obtained.This study provides the theoretical basis for the restoration and conservation of grasslands in mining areas by demonstrating examined the correlation between plant characteristics and soil properties in restored grasslands in alpine mining areas.

Mechanical properties and damage characteristics of solidified body-coal combination in continuous driving and gangue backfilling

Recovery of the coal buried under buildings,railways and water bodies and the residual coal in irregularly arranged fully mechanized mining faces is a common engineering problem facing underground coal mining.In this study,a mining technology of continuous driving and gangue backfilling(CDGB)was proposed.The technology,which can not only alleviate ground subsidence and gangue discharge,but also release the above-mentioned coals,contributes to green and efficient sustainable development of mining.The stability of the system of the solidified body-reserved coal pillar combination(S-C combination)is crucial to the CDGB technology.Therefore,it is of great significance to explore the mechanical and damage characteristics of S-C combination in the synergistic bearing process.First,four sets of differentshaped S-C combination specimens were fabricated and a S-C combination bearing structure in CDGB was constructed to explore the differences in mechanical characteristics and damage modes of different-shaped S-C combination specimens during CDGB.Subsequently,their surface strain field evolutions and acoustic emission(AE)response characteristics in the load-bearing process were obtained with the aid of the digital image correlation technique and the AE signal monitoring system.Furthermore,a damage evolution model based on AE parameters and mechanical parameters was established to clarify the damage evolution law.The following results were obtained:(1)The free area of S-C combination can serve as a quantitative index to evaluate the stability of the overburden control system;(2)The concept of critical value k of the free area was first proposed.When the free area exceeds the critical value k(free area ratio greater than 1.13),the deformation resistance and the free area changes becomes negatively correlated;(3)As the free area expands,the failure of the S-C combination specimen evolves from tensile failure to shear failure.The distribution characteristics of the axial strain field also verified such a change in the failure mode;(4)When the free area expands,the peak AE count gradually changes from“double peaks”to“a single peak”.In this process,the expansion of free area shortens the time for accumulating and releasing energy during loading.Micro cracks generated in the specimen change from a phased steep growth to a continuous increase,and the process in which micro cracks develop,converge,intersect and connect to form macro cracks accelerates.The damage evolution law concluded based on AE parameters and mechanical parameters can well characterize the damage evolution process of S-C combination,providing certain reference for the study on the synergistic bearing of S-C combination during CDGB.

The Influence of Acid on the RockMechanical Characteristics of Deep Shale in theWujiaping Formation

The microscopic characteristics and mechanical properties of rocks change after the action of acid on deep shale,which affects the fracturing effect.Accordingly,we designed and conducted indoor experiments related to the changes in macro and microscopic characteristics after the interaction of acid with the shale of Wujiaping Formation,based on which the characteristic law of fracture volume modification after acid fracturing was studied using numerical simulation.The results demonstrate that the pores and fractures are enlarged and the structure is significantly loosened after the acid immersion.And a 15%concentration of hydrochloric acid can effectively dissolve shale.Furthermore,the degree of acid-etching reaction is highly variable because of the different carbonate content,which reveals the strong inhomogeneity of the shale system in the Wujiaping Group reservoir section.After the acid interacted with the shale rock samples,the triaxial compressive strength,elastic modulus,and Poisson’s ratio of shale decreased.Moreover,the evaluation of the effect after acid fracturing simulated by fracturing software revealed that the smaller the value of elastic modulus in shale-based reservoirs,the more favorable the fracture volume modification.This discovery not only provides a theoretical basis for the expansion and extension patterns of acid-fracturing in carbonaceous shale formations but also offers research methods and theoretical insights for the fundamental exploration of other deep-seated oil and gas resources.

Preparation and property of seal coating for gas turbine compressor

Double-layer structure of seal coating which consisted of a Ni5Al bond coating and a Ni25 graphite top coating were prepared on steel substrate of gas turbine compressor cylinder block.Bond coating was prepared by atmospheric plasma spraying and top coating was prepared by flame spraying.The microstructure,mechanical properties and abradability of the coating were characterized by scanning elec-tron microscope(SEM),hardness tester,universal testing machine,thermal shock testing machine and abradability testing machine.The res-ults show that the overall spraying structure of the seal coating is uniform,the nickel metal phase is the skeleton supporting the entire coat-ing,and the coating is well bonded without separation.The seal coating has a bonding strength of not less than 7.7 MPa,excellent thermal stability,and thermal shock resistance cycle numbers at 500℃more than 50;the scratch length,deepest invasion depth and wear amount of the coating increase with rise of test temperature,with almost no coating adhesion,indicating that the seal coating has excellent abradability.

Shear resistance characteristics and influencing factors of root-soil composite on an alpine metal mine dump slope with different recovery periods

Artificial vegetation restoration is the main measure for vegetation restoration and soil and water conservation in alpine mine dumps on the Qinghai-Tibet Plateau,China.However,there are few reports on the dynamic changes and the influencing factors of the soil reinforcement effect of plant species after artificial vegetation restoration under different recovery periods.We selected dump areas of the Delni Copper Mine in Qinghai Province,China to study the relationship between the shear strength and the peak displacement of the root-soil composite on the slope during the recovery period,and the influence of the root traits and soil physical properties on the shear resistance characteristics of the root-soil composite via in situ direct shear tests.The results indicate that the shear strength and peak displacement of the rooted soil initially decreased and then increased with the increase of the recovery period.The shear strength of the rooted soil and the recovery period exhibited a quadratic function relationship.There is no significant function relationship between the peak displacement and the recovery period.Significant positive correlations(P<0.05)exists between the shear strength of the root-soil composite and the root biomass density,root volume density,and root area ratio,and they show significant linear correlations(P<0.05).There are no significant correlations(P>0.05)between the shear strength of the root-soil composite and the root length density,and the root volume ratio of the coarse roots to the fine roots.A significant negative linear correlation(P<0.05)exists between the peak displacement of the rooted soil and the coarse-grain content,but no significant correlations(P>0.05)with the root traits,other soil physical property indices(the moisture content and dry density of the soil),and slope gradient.The coarse-grain content is the main factor controlling the peak displacement of the rooted soil.

Tailoring the microstructural characteristics and enhancing creep properties of as-cast Mg-5Bi-5Sn alloy through Mn addition

The creep properties, microstructural characteristics and creep mechanisms of as-cast Mg-5Bi-5Sn(BT55) alloy without and with Mn(BTM550) addition were investigated via creep at 423, 448, and 473 K as well as stresses of 30, 50 and 75 MPa. The results indicate that adding Mn can result in the formation of primary and the dynamic precipitated α-Mn phases. In addition, the morphology of the precipitated Mg_(3)Bi_(2) phase and the orientation relationship between Mg_(2)Sn precipitates and α-Mg can be effectively modified. Tailoring the microstructural characteristics is responsible for the improved creep performance of BTM550 alloy. The dominant creep mechanisms in BT55 and BTM550 alloys are dislocation cross-slip and climb, respectively. Furthermore, twinning and pyramidal slip play an assisting part in both alloys during creep process.

Landscape Aesthetic Characteristics of Wulingyuan World Natural Heritage Property and Realization Path of Aesthetic Education Value

Wulingyuan is a world natural heritage property mainly dominated by rare quartz sandstone peak forest landscape at home and abroad and supplemented by karst landscapes,with a large number of geological and historical sites,biological and ecological landscape and unique cultural landscapes.Preserving the secluded and beautiful scenery environment,biological environment and ecosystem of subtropical zone,Wulingyuan presents a splendid and magnificent landscape,with high aesthetic value,and becomes an important practice base of aesthetic education.The aesthetic education value of Wulingyuan World Natural Heritage Property can be realized by systematically studying and presenting the aesthetic education value of Wulingyuan World Natural Heritage Property,developing a series of aesthetic education courses to lead tourists into the world of Wulingyuan aesthetic education,carrying out a series of popular science activities of“Wulingyuan World Natural Heritage Property Entering Campus”,and incorporating into the aesthetic education curriculum system of schools,etc.This paper analyzes the landscape aesthetic characteristics of Wulingyuan World Natural Heritage Property thoroughly,which indicates the direction for realizing the aesthetic education value of the property,and also provides a reference for realizing the aesthetic education value of similar world natural heritage property.

Cavitation and electrochemical characteristics of thermal spray coating with sealing material

Steel applied in ocean environment is exposed to corrosion and cavitation and is subject to increasing damages. To prevent this, anti-corrosion thermal spray coating technique is widely used. The low-temperature thermal spray coating was performed with 85%Al-14.5%Zn-0.5%Zr for ship materials and various sealing materials were applied to improve its durability, and the electrochemical behavior and cavitation characteristics were observed. The results show that the sealing improves all the properties of the materials. Hybrid ceramic and fluoro-silicon sealing materials show good electrochemical characteristics, and the fluoro-silieon sealing material shows the best anti-cavitation characteristics.

A new evaluation method of gel's dynamic sealing characteristic in porous media

Water shutoff through injection wells is one of the most important techniques used for water injection profile control and modification in severely heterogeneous reservoirs,aiming at stabilizing oil production.It has been widely reported that the effectiveness and efficiency of water shutoff using gel is mostly dependent on the gel dynamic sealing properties in the porous media.Firstly the gelation strength and gelation time of polymer gel were evaluated.Then,core flowing experiments were conducted before and after gelation in a 32 m long sand pack.In addition,water flooding core experiments were also carried out in a long core of 80 cm before and after injecting gel system to check the reliability of this evaluation method.The experimental results show that moderate-strength gel can be formed at 65 °C.According to the integrated evaluation of the plugging coefficient,plugging strength and water breakthrough time,the gel particles are capable of migrating to a distance of 7.47 m from the injection point of the 32 m long sand pack during the water injection process after gelation.Based on sands gelation status and effluent analyses,the effective migration distance of the gel particles is 4-14 m.Through the core flooding experiments using the 80 cm heterogeneous core,it is evidenced that the gel can be formed in the deep reservoir(40.63% of total length) with the plugging strength as high as 6.33 MPa/m,which leads to extra oil recovery of 10.55% of original oil in place(OOIP) by water flooding after gel treatment.

Dielectric properties and temperature increase characteristics of zinc oxide dust from fuming furnace

Cavity perturbation method was used to determine the dielectric properties （ε′,ε″, and tanδ） of zinc oxide dust in different apparent densities. The process was conducted to study the microwave-absorption properties of zinc oxide dust and the feasibility of microwave roasting zinc oxide dust to remove fluorine and chlorine. The dielectric constant, dielectric loss, and loss tangent were proportional to the apparent density of zinc oxide dust. The effects of sample mass and microwave power on the temperature increase characteristics under the microwave field were also studied. The results show that the apparent heating rate of the zinc oxide dust increases with the increase in microwave roasting power and decreases with the increase in the sample mass. The temperature of the samples reaches approximately 800 ＆#176;C after microwave treatment for 8 min, which indicates that the zinc oxide dust has strong microwave-absorption ability.

Characteristic atom sequences of Nb-Mo alloys system in BCC structure and properties of disordered alloys

Comprehensively considering energy, volume and electronic structure of alloys, the ninth equation was determined as the interaction function of Nb-Mo alloys system in BCC structure on the basis of idea of systematic science of alloys, experimental lattice constants and heats of formation of disordered Nb（1-x）Mox alloys. The structural parameters and properties of Nb and Mo characteristic atoms sequences and corresponding characteristic crystals sequences were determined in Nb-Mo alloys system. The electronic structure and physical properties of disordered Nb（1-x）Mox alloys system were calculated according to concentration of characteristic atoms of disordered alloys. The change trend of physical properties is the same as that of electronic structure.

Analysis on the Functions and Properties of the Preliminarily Determined Characteristics Listed in DUS Test Guideline of Tagetes L.

[Objective] This study aimed to investigate the functions and properties of the preliminarily determined characteristics listed in DUS test guideline of Tagetes L., and explore the representativeness and comprehensiveness of this group of characteristics in DUS test. [Method] Based on the functions and properties of the characteristics, the described plant part （s）, observation stage, expression pattern and observation method of each characteristic were analyzed to illustrate the representativeness and comprehensiveness of the combination of this group of characteristics in above functions and properties. [Result] As for described plant part（s）, there are 5 characteristics describing plant as a whole, 3 characteristics describing stem, 6 characteristics describing leaf, 23 characteristics describing flower and 1 characteristic describing physiological feature. As for observation stage, there are 1 characteristic needing to be observed in the stage of seedling, 1 characteristic in the stage of beginning of flowering and other 36 characteristics in the stage of fully flowering. As for the expression pattern, there are 10 qualitative characteristics, 9 pseudo-qualitative characteristics and 19 quantitative characteristics. As for the observation method, there are 30 characteristics using VG as the observation method, and 8 characteristics using MS. [Conclusion] In view of the variation and morphological properties of marigold, this group of characteristics are representative and comprehensive, and ensure the accuracy and easiness of DUS test of Tagetes L., thereby achieving the reasonable combination of characteristics in described plant parts, observation stages, expression patterns and observation methods.

Experimental study of the dynamic mechanical responses and failure characteristics of coal under true triaxial confinements

Investigations on the dynamic mechanical properties and failure mechanisms of coal under in-situ stress is essential for the prevention of dynamic disasters in deep coal mines.Thus,a modified true triaxial Hopkinson bar was employed to explore the dynamic mechanical behaviors of coal at different confining pressures(0–20 MPa)and strain rates(40–220 s^(-1)).The results show that the dynamic peak stress is positively correlated with lateral static pre-stressσy andσz,but negatively correlated with axial static prestressσx.At approximate strain rates,increasing the lateral static pre-stress facilitates increasing the dynamic peak stress,but the minimum lateral static pre-stress is the primary factor limiting a significant increase in dynamic peak stress of coal.Furthermore,the dynamic differential stress is linearly related to the logarithm of strain rate,and the peak strain varies linearly with strain rate.However,there is no significant correlation between confining pressure and peak strain.Moreover,X-ray CT images and photographic fracture observations of coal samples show the failure patterns under uniaxial and triaxial conditions are splitting failure and shear failure,respectively.The device provides a viable approach for fully comprehending the dynamic mechanical behaviors of rock-like material in complex stress conditions.

Mechanical and acoustic emission characteristics of anhydrite rock under freeze-thaw cycles

To study the damage mechanisms of anhydrite rock under freeze-thaw cycles, the physicalmechanical properties and the microcracking activities of anhydrite rock were investigated through mass variation, nuclear magnetic resonance, scanning electron microscope tests, and uniaxial compression combined with acoustic emission(AE) tests. Results show that with the increase of freeze-thaw processes,the mass, uniaxial compression strength, and elastic modulus of the anhydrite specimens decrease while the porosity and plasticity characteristics increase.For example, after 120 cycles, the uniaxial compression strength and elastic modulus decrease by 46.54% and 60.16%, and the porosity increase by 75%. Combined with the evolution trend of stressstrain curves and the detected events, three stages were labeled to investigate the AE characteristics in freeze-thaw weathered anhydrite rock. It is found that with the increase of freeze-thaw cycles, the proportions of AE counts in stage Ⅰ and stage Ⅱ show a decaying exponential trend. Contrarily, the proportion of AE counts in stage Ⅲ displays an exponential ascending trend. Meanwhile, as the freeze-thaw cycles increase, the low-frequency AE signals increase while the intermediate-frequency AE signals decrease. After 120 cycles, the proportion of low-frequency AE signals increases by 168.95%, and the proportion of intermediate-frequency AE signals reduces by 81.14%. It is concluded that the microtensile cracking events occupy a dominant position during the loading process. With the increase of freeze-thaw cycles, the b value of samples decreases.After 120 cycles, b value decreases by 27.2%, which means that the proportion of cracking events in rocks with small amplitude decreases. Finally, it is proposed that the freeze-thaw damage mechanism of anhydrite is also characterized by the water chemical softening effect.

Sealing properties and structure optimization of packer rubber under high pressure and high temperature

During hydraulic fracturing operations of low-permeability reservoirs,packers are the key component to ensure the success of multistage fracturing.Packers enable sections of the wellbore to be sealed off and separately fractured by hydraulic pressure,one at a time,while the remainder of the wellbore is not affected.However,reliable sealing properties of the packer rubber are required to meet the high-pressure and high-temperature(HPHT)conditions of reservoirs(such as 70 MPa and 170 ℃).In this study,the structures of the packer rubber with two different materials are optimized numerically by ABAQUS and validated by experiments.The optimization process starts from the packer rubber with a conventional structure,and then,the weakest spots are identified by ABAQUS and improved by slightly varying its structure.This process is iterative,and the final optimized structure of a single rubber barrel with expanding back-up rings is achieved.For the structure of three rubber barrels with metallic protective covers,both HNBR and AFLAS fail under HPHT conditions.For the final optimized structure,the packer rubber made of AFLAS can work better under HPHT than that made of HNBR which ruptures after setting.The results show that the optimized structure of a single rubber barrel with expanding back-up rings and the material AFLAS are a good combination for the packer rubber playing an excellent sealing performance in multistage fracturing in horizontal wells.

Friction Characteristics of Mechanical Seals with Laser-textured Seal Faces

Heat generated by friction between faces of mechanica l seals is a major factor that causes deterioration of the seals and shortens th eir service life. Excessive temperature rise can greatly alter the seal geometry and vaporize the sealing fluid, resulting in friction of boundary lubrication. These effects on face seals usually lead to excessive leakage and ultimately ren der the seal inoperable. In order to maintain the reliability of seals, high fri ction and unwanted wear must be avoided. Using the laser-texturing process to produce regular micro-surface structures is a fast and convenient technique compared to some more conventional etching or erosion technique currently used by the seal industry for various grooved face seals. Indeed, by using a pulse laser, better control is obtained on the geometr y, size and pore ratio of seal rings made of metallic or ceramic materials. In t his study, seal rings are made of silicon carbide and carbon. Mating faces of th e rings are polished and only silicon carbide rings are laser-textured. The las er texturing can be controlled to produce spherical pores at selected diameters, depths and pore ratio. The textured rings are then super-polished to remove th e bulges formed on the pores rims. After this process the average pore diameter, pore depth and pore ratio reach the predetermined parameter. Some untextured ri ngs are also treated to the same surface roughness and served as a reference for comparison of the textured rings. A special test rig is used to simulate a mech anical seal system and to measure the effect of the laser texturing on friction and seal performance. Tests are performed at various rotational speeds and vario us axial loads. Compared with the conventional mechanical seals, temperature rise, friction torq ue and friction coefficient of mechanical seals with laser-textured seal faces are much lower. These preliminary results show the potential of improving fricti on performance and increasing seal life with laser-textured seal faces.

Gas Film Disturbance Characteristics Analysis of High-Speed and High-Pressure Dry Gas Seal

The dry gas seal（DGS） has been widely used in high parameters centrifugal compressor, but the intense vibrations of shafting, especially in high-speed condition, usually result in DGS＇s failure. So the DGS＇s ability of resisting outside interference has become a determining factor of the further development of centrifugal compressor. However, the systematic researches of which about gas film disturbance characteristics of high parameters DGS are very little. In order to study gas film disturbance characteristics of high-speed and high-pressure spiral groove dry gas seal（S-DGS） with a flexibly mounted stator, rotor axial runout and misalignment are taken into consideration, and the finite difference method and analytical method are used to analyze the influence of gas film thickness disturbance on sealing performance parameters, what＇s more, the effects of many key factors on gas film thickness disturbance are systematically investigated. The results show that, when sealed pressure is 10.1MPa and seal face average linear velocity is 107.3 m/s, gas film thickness disturbance has a significant effect on leakage rate, but has relatively litter effect on open force; Excessively large excitation amplitude or excessively high excitation frequency can lead to severe gas film thickness disturbance; And it is beneficial to assure a smaller gas film thickness disturbance when the stator material density is between 3.1 g/cm3 to 8.4 g/cm3; Ensuring sealing performance while minimizing support axial stiffness and support axial damping can help to improve dynamic tracking property of dry gas seal. The proposed research provides the instruction to optimize dynamic tracking property of the DGS.

Drying characteristics, functional properties and in vitro digestion of purple potato slices dried by different methods

The drying characteristics,physico-chemical and functional properties,as well as starch digestibility,of purple potato slices dried using different methods(such as,vacuum freeze-drying,VFD;hot-air drying,HAD;air-impingement jet drying,AIJD;and far-infrared assisted heat-pump drying,FIHPD)were investigated.Drying rate was the highest(3.0 g 100 g^-1 min^-1)using AIJD,followed by FIHPD and HAD,and the rate of VFD was the lowest one(0.3 g 100 g^-1 min^-1).Drying data were fitted to 12 thin-layer drying models,with the Midilli model giving the best predictions.Moreover,AIJD showed higher diffusivity(5.5×10^-10 m^2 s^–1)and energy efficiency(55 J g^-1)than any other drying method used in this study.With reference to the samples dried by VFD,the starch granules of the samples obtained by HAD,FIHPD,and AIJD exhibited different extent of disruption,which significantly increased their water absorption capacity,swelling power,and in vitro digestibility,but decreased the peak viscosity.The sample resulting from AIJD had the greatest water absorption capacity(7.9 g g^-1)and solubility(21.6%),but the smallest syneresis rate(48%).Good correlation coefficients(R^2>0.98)implied that the pseudofirst order kinetic model adequately described the rate and extent of starch digestion of dried potato flours.Samples from AIJD and FIHPD showed the highest digestibility percentages,reaching to 72.4 and 72.5%.Based on the drying rate,specific energy consumption,functional properties and digestibility,AIJD appeared to be quite effective and suitable to be transferred on the industry scale.