Engine Performance and Exhaust Emissions of Peanut Oil Biodiesel

The engine performance and exhaust emissions of biodiesel produced from peanut oil must be evaluated to assess its potential as an alternative diesel fuel. In this study, two diesel engines rated at 14.2 kW (small) and 60 kW (large) were operated on pure peanut oil biodiesel (PME) and its blends with a reference diesel (REFDIESEL). Results showed that comparable power and torque were delivered by both the small and large engines when ran on pure PME than on REFDIESEL while brake-specific fuel consumption (BSFC) was found to be higher in pure PME. Higher exhaust concentrations of nitrogen oxides (NOx), carbon dioxide (CO2) and total hydrocarbons (THC) and lower carbon monoxide (CO) emissions were observed in the small engine when using pure PME. Lower CO2, CO and THC emissions were obtained when running the large engine with pure PME. Blends with low PME percentage showed insignificant changes in both engine performance and exhaust emissions as compared with the reference diesel. Comparison with soybean biodiesel indicates similar engine performance. Thus, blends of PME with diesel may be used as a supplemental fuel for steady-state non-road diesel engines to take advantage of the lubricity of biodiesel as well as contributing to the goal of lowering the dependence to petroleum diesel.

A Comparative Study on the Engine Performance and Exhaust Emissions of Biodiesel from Various Vegetable Oils and Animal Fat

The potential of biodiesel fuels from various vegetable oil sources such as sunflower (SFME), safflower (SAFME), peanut (PME) and canola (CME) as well as from low-cost chicken fat (CFME) to supplement increasing biodiesel demands must be evaluated in terms of the corresponding engine performance and exhaust emissions. In this study, two diesel engines rated at 14.2 kW (small) and 60 kW (large) were operated by using the different biodiesel fuels and a reference diesel. Results showed that both the small and large engines delivered similar power when using biodiesel fuels in the expense of higher brake-specific fuel consumptions (BSFC). Higher exhaust concentrations of nitrogen oxides (NOx) and carbon dioxide (CO2) while lower carbon dioxide (CO) and negligible sulfur dioxide (SO2) emissions were observed in both engines. Total hydrocarbon emissions (THC) were higher in both engines when using SME, SFME and CME but comparable when using CFME, SAFME and PME in the large engine. Thus, with the increasing demand for biodiesel, alternative feedstock sources such as those used in this study may be utilized to take advantage of their availability, renewability and environmental benefits.

Effect of exhaust gas recirculation and intake pre-heating on performance and emission characteristics of dual fuel engines at part loads

Achieving simultaneous reduction of NOx,CO and unburned hydrocarbon(UHC) emissions without compromising engine performance at part loads is the current focus of dual fuel engine research.The present work focuses on an experimental investigation conducted on a dual fuel(diesel-natural gas) engine to examine the simultaneous effect of inlet air pre-heating and exhaust gas recirculation(EGR) ratio on performance and emission characteristics at part loads.The use of EGR at high levels seems to be unable to improve the engine performance at part loads.However,it is shown that EGR combined with pre-heating of inlet air can slightly increase thermal efficiency,resulting in reduced levels of both unburned hydrocarbon and NOx emissions.CO and UHC emissions are reduced by 24% and 31%,respectively,The NOx emissions decrease by 21% because of the lower combustion temperature due to the much inert gas brought by EGR and decreased oxygen concentration in the cylinder.

Modeling the Effect of Variable Timing of the Exhaust Valves on SI Engine Emissions for Greener Vehicles

The problem with fixed valve timing that the valve train is set by the automaker for peak efficiency running at a specific point in the engine’s operating range. When the vehicle is moving slower or faster than this ideal operating point the engine’s combustion cycle fails to properly burn the air/fuel mixture leading to considerably compromised engine performance and wastes fuel. Variable Valve Timing (VVT) is a solution developed to overcome this engine deficiency, dynamically altering the valve's opening and closing for optimal performance at any speed. The intension in this work is to contribute towards pursuing the development of variable valve timing (VVT) for improving the engine performance. This investigation covers the effect of exhaust valve opening (EVO), and closing (EVC) angle on engine performance and emissions. The aim is to optimize engine power and brake specific fuel consumption (BSFC) where the effect of engine speed has also been considered. Power, BMEP, BSFC, NO, and CO were calculated and presented to show the effect of varying valve timing on them for all the valve timing cases. The calculations of engine performance were carried out using the simulation and analysis engineering software: LOTUS”, and engine emissions were calculated using “ZINOX” program. Sensitivity analysis shows that the reduction of 10% of (EVO) angle gave a reduction of around 2.5% in power and volumetric efficiency, also a slight increase in nitrogen oxide (NO) and carbon monoxide (CO), while a 10% decrease in (EVC) causes around 1% improvement in Power. The effects of different (VVT) from the simulations are analyzed and compared with those in the reviewed literature.

INVESTIGATION IN REDUCING EXHAUST EMISSIONS FROM TWO STROKE MOTORCYCLES

Test results of reducing two stroke motorcycle emissions with new type carburettors and electronic fuel injection systems are presented. Analyses and comparison between different systems are discussed. The adoption of electronically controlled injection and corresponding electronic control technique is an effective measure of prolonged vitality to improve emissions from two stroke motorcycles. Suggestions about the strategic steps of China′s motorcycle emission control are proposed.

Validation of an Emission Model for a Marine Diesel Engine with Data from Sea Operations

In this study,a model is developed to simulate the dynamics of an internal combustion engine,and it is calibrated and validated against reliable experimental data,making it a tool that can effectively be adopted to conduct emission predictions.In this work,the Ricardo WAVE software is applied to the simulation of a particular marine diesel engine,a four-stroke engine used in the maritime field.Results from the bench tests are used for the calibration of the model.Finally,the calibration of the model and its validation with full-scale data measured at sea are presented.The prediction includes not only the classic engine operating parameters for a comparison with surveys but also an estimate of nitrogen oxide emissions,which are compared with similar results obtained with emission factors.The calibration of the model made it possible to obtain an overlap between the simulation results and real data with an average error of approximately 7%on power,torque,and consumption.The model provides encouraging results,suggesting further applications,such as in the study on transient conditions,coupling of the engine model with the ship model for a complete simulation of the operating conditions,and optimization studies on consumption and emissions.The availability of the emission data during the sea trial and validated simulation results are the strengths and novelties of this work.

Ultrafine particle emission characteristics of diesel engine by on-board and test bench measurement

This study investigated the emission characteristics of ultra.fine particles based on test bench and on-board measurements. The bench test results showed the ultrafine particle number concentration of the diesel engine to be in the range of （0.56-8.35）×10^8 cm^-3. The on-board measurement results illustrated that the ultra_fine particles were strongly correlated with changes in real-world driving cycles. The particle number concentration was down to 2.0 ×10^6 cm^-3 and 2.7 ×10^7 cm^-3 under decelerating and idling operations and as high as 5.0×10^8 cm^-3 under accelerating operation. It was also indicated that the particle number measured by the two methods increased with the growth of engine load at each engine speed in both cases. The particle number presented a ＂U＂ shaped distribution with changing speed at high engine load conditions, which implies that the particle number will reach its lowest level at medium engine speeds. The particle sizes of both measurements showed single mode distributions. The peak of particle size was located at about 50-80 nm in the accumulation mode particle range. Nucleation mode particles will significantly increase at low engine load operations like idling and decelerating caused by the high concentration of unburned organic compounds.

Design and optimization of exhaust gas aftertreatment system for a heavy-duty diesel engine

Diesel engines meeting the latest emission regulations must be equipped with exhaust gas aftertreatment system,including diesel oxidation catalysts(DOC),diesel particulate filters(DPF),and selective catalytic reduction(SCR).However,before the final integration of the aftertreatment system(DOC+DPF+SCR)and the diesel engine,a reasonable structural optimization of the catalytic converters and a large number of bench calibration tests must be completed,involving large costs and long development cycles.The design and optimization of the exhaust gas aftertreatment system for a heavy-duty diesel engine was proposed in this paper.Firstly,one-dimensional(1D)and threedimensional(3D)computational models of the exhaust gas aftertreatment system accounting for the structural parameters of the catalytic converters were established.Then based on the calibrated models,the effects of the converter’s structural parameters on their main performance indicators,including the conversion of various exhaust pollutants and the temperatures and pressure drops of the converters,were studied.Finally,the optimal design scheme was obtained.The temperature distribution of the solid substrates and pressure distributions of the catalytic converters were studied based on the 3D model.The method proposed in this paper has guiding significance for the optimization of diesel engine aftertreatment systems.

Development of 2D Temperature and Concentration Measurement Method Using Tunable Diode Laser Absorption Spectroscopy

Exhaust gas temperature is an important factor in NOx, THC and PM emissions of engines. Especially 2D temperature and concentration distribution plays an important role for the engine efficiency. A thermocouple is intrinsically a point temperature measurement method and noncontact 2D temperature distribution cannot be attained by thermocouples. Recently, as a measurement technique with high sensitivity and high response, laser diagnostics has been developed and applied to the actual engine combustions. With these engineering developments, transient phenomena such as start-ups and load changes in engines have been gradually elucidated in various conditions. In this study, the theoretical and experimental research has been conducted in order to develop the noncontact and fast response 2D temperature and concentration distribution measurement method. The method is based on a Computed Tomography （CT） method using absorption spectra of water vapor at 1388 nm. It has been demonstrated that the method has been successfully applied to engine exhausts to measure 2D temperature distributions.

Application of Waste Biomass Pyrolysis Oil in a Direct Injection Diesel Engine： For a Small Scale Non-Grid Electrification

The population which could not access to electricity was around 1.2 billion in 2010 and is distributed in many low developing countries. With the increase in the population and the economic growth in those countries, waste generation is growing rapid especially for the organic and the plastic, and the uncontrolled waste disposal is becoming more serious issues to manage it. The interest on waste to energy is growing by the above drivers. This research was carried out for aiming to the real world adaption at the minimum cost of the pyrolysis oil from waste biomass in a diesel engine, mainly for electricity generation. The proposal of the appropriate adaptable blend ratio was the major scope rather than the optimization of the engine parameters. For the sake of it, the pyrolysis oil of the waste biomass was produced from a gasification pilot plant in Japan and blended with biodiesel at minimum effort. A small single cylinder diesel engine （direct injection） was used for the experiment with regard to full load power-output, exhaust emissions and fuel consumption.

Performance of a Direct Injection of IC Engine on SVO and Biodiesel from Multiple Feedstocks

Straight Vegetable Oil (SVO) is a promising biofuel with a low energy input to energy output ratio. Successful use of SVO in engines depends on engine performance, wear and emissions. This study focuses on short term engine emissions and performance. This research uses oils produced in Colorado as a full diesel fuel substitute in a modified single cylinder engine. This engine testing was conducted in the laboratory. The test engine was a Yanmar TF140E, which is naturally aspirated and uses low pressure (~140 bar) mechanical direct injection. The engine fuel system was modified to accommodate a 2-tank custom SVO kit. The SVO was heated to 75 °C. Fuel economy and emissions measurements were performed for petroleum diesel, four different vegetable oils (sunflower, canola, camelina, and soybean) and their biodiesel derivatives. Fuel mass flow, oxides of nitrogen (NOX), total hydrocarbons (THC), carbon monoxide (CO), and particulate matter were measured. No engine degradation was experienced through approximately 50 hrs of testing on SVO and 50 hrs of testing on biodiesel. Overall engine emissions for SVO and biodiesel, with the exception of THC for biodiesel, were higher than petroleum diesel. More favorable biofuel emissions comparisons to diesel are expected with other engine designs based on data from various literature sources. Data comparing raw and refined SVO indicate that refined vegetable oil produces lower particulate matter (PM) emissions. General trends were observed showing that oils with higher levels of polyunsaturated fats (e.g. C18:1, C18:2, and C18:3) produce higher levels of NOX and THC’s.

Instrumental and bio-monitoring of heavy metal and nanoparticle emissions from diesel engine exhaust in controlled environment

In the present article we characterized the emissions at the exhaust of a Common Rail （CR） diesel engine, representative of lightduty class, equipped with a catalyzed diesel particulate filter （CDPF） in controlled environment. The downstream exhausts were directly analyzed （for PM, CO, CO/, Oz, HCs, NOx） by infrared and electrochemical sensors, and SEM-EDS microscope; heavy metals were chemically analyzed using mosses and lichens in bags, and glass-fibre filters all exposed at the engine exhausts. The highest particle emission value was in the 7-54 nm size range; the peak concentration rose until one order of magnitude for the highest load and speed. Particle composition was mainly carbonaceous, associated to noticeable amounts of Fe and silica fibres. Moreover, the content of Cu, Fe, Na, Ni and Zn in both moss and lichen, and of A1 and Cr in moss, was significantly increased. Glass-fibre filters were significantly enriched in A1, B, Ba, Cu, Fe, Na, and Zn. The role of diesel engines as source of carbonaceous nanoparticles has been confirmed, while further investigations in controlled environment are needed to test the catalytic muffler as a possible source of silica fibres considered very hazardous for human health.

Experimental Investigation for NO_x Emission Reduction in Hydrogen Fueled Spark Ignition Engine Using Spark Timing Retardation, Exhaust Gas Recirculation and Water Injection Techniques

The experimental tests were carried out on a single cylinder hydrogen fueled spark ignition(SI)generator set with different spark timings(4-20℃A bTDC),exhaust gas recirculation(EGR)up to 28% by volume and water injection up to 1.95 kg/h(maximum water to fuel mass ratio of 8:1).The engine speed was kept constant of 3000 r/min.The NOx emission and thermal efficiency of engine with gasoline and hydrogen fuel operation at 1.4 kW power output are 5 g/kWh and 12.1 g/kWh,and 15% and 20.9% respectively.In order to reduce the NOx emission at source level,retarding spark timing,exhaust gas recirculation(EGR),and water injection techniques were studied.Nox emission decreased with spark timing retardation,EGR,and water injection.NOx emission with hydrogen at 1.4 kW power output decreased from 12.1 g/kWh with maximum brake torque(MBT)spark timing(10℃A bTDC)to 8.1 g/kWh with retarded spark timing(4℃A bTDC)due to decrease in the in-cylinder peak pressure and temperature.The Nox emission decreased to 6.1 g/kWh with 20% EGR due to thermal and chemical dilution effect.However,thermal efficiency decreased about 33% and 17% with spark timing retardation and 20EGR respectively as compared to that of MBT spark timing.But,in the case of water injection,the NOx emission decreased significantly without affecting the thermal efficiency of the engine and it is 5.6 g/kWh with water-hydrogen ratio of 4:1(water flow rate of 0.92 kg/h).Water injection is the best suitable method to reduce the NOx emission in a hydrogen fueled engine compared with the spark timing retardation and EGR technique.

Performance and emission characteristics of a diesel engine operating on different water in diesel emulsion fuels:optimization using response surface methodology(RSM)

The nitrogen oxide(NOx)release of diesel engines can be reduced using water in diesel emulsion fuel without any engine modification.In the present paper,different formulations of water in diesel emulsion fuels were prepared by ultrasonic irradiation.The water droplet size in the emulsion,polydisperisty index,and the stability of prepared fuel was examined,experimentally.Afterwards,the performance characteristics and exhaust emission of a single cylinder air-cooled diesel engine were investigated using different water in diesel emulsion fuels.The effect of water content(in the range of 5%-10% by volume),surfactant content(in the range of 0.5%-2% by volume),and hydrophilic-lipophilic balance(HLB)(in the range of 5-8)was examined using Box-Behnken design(BBD)as a subset of response surface methodology(RSM).Considering multi-objective optimization,the best formulation for the emulsion fuel was found to be 5%water,2% surfactant,and HLB of 6.8.A comparison was made between the best emulsion fuel and the neat diesel fuel for engine performance and emission characteristics.A considerable decrease in the nitrogen oxide emission(-18.24%)was observed for the best emulsion fuel compared to neat diesel fuel.

Performance and combustion study of a low heat rejection engine running with biogas–diethyl ether–diesel

The present research focuses on addressing the faster depletion of fossil fuels and environmental pollution in addition to the energy crisis that hinders the progress of a nation.In the current research,waste banana leaves were considered as substrates for biogas production.Biogas is taken as the primary fuel in dual fuel(DF)operations to maximize possible diesel savings.The performance and combustion assessment were executed in a low heat rejection(LHR)engine using 5%diethyl ether by volume blended with diesel(5DEE)as pilot fuel.The combustion attributes of the engine reveal that the apex of net heat release rate(NHRR)curve retarded a bit as compared to apex of base result.The peak cylinder pressure was noted to be 6.19 MPa in the LHR engine running with 5DEE+biogas at 11.7°crank angle(CA)after top dead center(aTDC)compared to 5.23 MPa for the diesel alone operation at the same position.The apex point for NHRR was observed to be 54.51 J(°)^(−1)for 5DEE+biogas in LHR engine positioned at 3.2°aTDC.The brake thermal efficiency at full engine load operation decreased by 12.7%and 5.2%for biogas substitutions of 0.8 kg h^(−1)with diesel and 5DEE,respectively,compared to the base result.The smoke opacity and nitric oxide emissions were reduced during the DF run accompanied by diethyl ether as a fuel additive.

Quantification of emission variability for off-road equipment in China based on real-world measurements

The objective of this paper is to quantify the variability in emissions of off-road equipment using a portable emission measurement system.A total of 53 commonly used equipment for agriculture,base construction,paving construction,and material handling were selected.Time-based and fuel-based emissions were quantified by different duty and engine modes.Three duty modes(idling,moving,and working)were used.Ten engine modes were defined based on normalized engine revolutions-per-minute and manifold absolute pressure,respectively.Composite emission factors taking into account both duty modes and its corresponding time percentage during a typical duty cycle were estimated.Results showed that there existed a large off-road equipment variability in emissions.Depending on duty and engine modes,time-based NO emissions ranged from 3.1 to 237.9,29.1‒1475.6,83.2‒681.6,and 3.2‒385.2 g/h for agriculture,base construction,paving construction and material handling equipment,respectively while for fuel-based NO emissions these ranges were 5.3‒52.0,11.7‒69.0,4.8‒30.8,and 11.0‒54.6 g/kg,respectively.Furthermore,emission factors derived from this study exhibited a much larger variability compared to those used in NONROAD by US EPA and National Guideline for Off-road Equipment of China.This implied that localized measurements of emissions are needed for improvement of accuracy of emission inventory.Furthermore,both equipment types and operations should be considered for development of emission inventory and control strategy.

NOx Emission Reduction Technology for Marine Engine Based on Tier-Ⅲ:A Review

The development of maritime trade has greatly promoted the development of diesel engines.However,with the increasingly serious environmental problems,more and more attention has been paid to the exhaust emissions of high-power marine diesel engines.The restrictions on SOx have been implemented globally,and the limitation of the NO,will be the next priority.This paper illustrates(a)Principle and research progress of NOx emissions-reduction technology of marine diesel engine;(b)Summary of advantages and disadvantages among various reduction technologies and their reduction effects;(c)The application effect of mainstream technology on board.Firstly,since exhaust gas recirculation(EGR)can achieve Tier-Ⅲ directly from Tier-Ⅰ without considering the increased fuel consumption.It is deemed as the most promising technology to reduce emissions by controlling combustion condition.However,EGR has shortcomings of excessive increase in ftiel consumption and generation of waste water,which need to be solved immediately.Secondly,selective catalytic reduction(SCR)is the most effective and straightforward means to achieve Tier-Ⅲ.Despite of the continuous optimization of SCR unit volume,the problem of scrap catalyst seriously limits its wide application.How to match the supercharger more efficiently is a key factor in choosing between high and low pressure SCR.Thirdly,nature gas(NG)engines are capable of achieving a reduction in NOx,but in order to meet the requirements of Tier-Ⅲ,it still needs to be assisted by other technologies.The emissions of hydrocarbon(HC)and CO in NG engines are huge defects that must be solved.Lastly,technologies such as the Miller cycle,Two-stage supercharging and mixed-water combustion can also reduce emissions but were rarely used alone.These technologies can be combined with EGR,SCR and NG engines to optimize the enginesJ economy and emission characteristics.

Transient emission simulation and optimization o turbocharged diesel engine

In order to alleviate the pressure of experi- mental research of turbocharged diesel engine under transient operations, a whole process simulation platform for turbocharged diesel engine under transient operations was established based on the multi-software coupling technologies of Matlab/Simulink, GT-Power, STAR-CD and artificial neural network. Aimed at the contradiction of NOx and soot emission control with exhaust gas recirculation （EGR） of turbocharged diesel engine under transient operations, on this simulation platform, a transient EGR valve control strategy was proposed, which adjusted the EGR valve in adjacent level based on the feedback of its opening according soot control limit under transient operations. Simulation and experimental results prove that the transient emission optimization effect of this control strategy is obvious. On the one hand, compared with the previous control strategy, which closed the EGR valve during the whole transient operations, soot emission is slightly increased by 9.5%, but it is still 9% lower than the control limit. On the other hand, compared with the previous control strategy, NOx transient emission is reduced by 44%.

Mesozoic–Cenozoic stress field magnitude in Sichuan Basin, China and its adjacent areas and the implication on shale gas reservoir: Determination by acoustic emission in rocks

The Sichuan Basin is one of the vital basins in China,boasting abundant hydrocarbon reservoirs.To clarify the intensity of the tectonic stress field of different tectonic episodes since the Mesozoic and to identify the regional dynamic background of different tectonic movements in the Sichuan Basin and its adjacent areas,the characteristics of the acoustic emission in rocks in different strata of these areas were researched in this paper.Meanwhile,the tectonic stress magnitude in these areas since the Mesozoic was restored.The laws state that the tectonic stress varied with depth was revealed,followed by the discussion of the influence of structural stress intensity on structural patterns in different tectonic episodes.These were conducted based on the paleostress measurement by acoustic emission method and the inversion principle of the stress fields in ancient periods and the present,as well as previous research achievements.The results of this paper demonstrate that the third episode of Yanshanian Movement(Yanshanian III)had the maximum activity intensity and tremendously influenced the structural pattern in the study area.The maximum horizontal principal stress of Yanshanian III varied with depth as follows:0.0168 x+37.001(MPa),R^2=0.8891.The regional structural fractures were mainly formed in Yanshanian III in Xujiahe Formation,west Sichuan Basin,of which the maximum paleoprincipal stress ranging from 85.1 MPa to 120.1 MPa.In addition,the law stating the present maximum horizontal principal stress varies with depth was determined to be 0.0159 x+10.221(MPa),R^2=0.7868 in Wuling Mountain area.Meanwhile,it was determined to be 0.0221 x+9.4733(MPa),R^2=0.9121 in the western part of Xuefeng Mountain area and 0.0174 x+10.247(MPa),R^2=0.8064 in the whole study area.These research results will not only provide data for the simulation of stress field,the evaluation of deformation degree,and the prediction of structural fractures,but also offer absolute geological scientific bases for the elevation of favorable shale gas preservation.

EXPERIMENTAL INVESTIGATION ON TWO- DIMENSIONAL UNSTEADY COLD FLOW IN MPC EXHAUST MANIFOLD

The gas flow in exhaust manifolds has much effect on scavenge, pumping loss and exhaust energy utilization of turbocharged diesel engines. This paper presented experimental investigation on two dimensional unsteady flow in MPC(modular pulse converter) exhaust manifold model. The pressure and velocity distributions in six sections of the manifold model were measured when the diesel engine was motored. The probe with slitted sleeve was used to determine flow direction. The experimental results show that velocity distributions vary with place and time; the pressure traces at different points of the same section are not different obviously.