Common Rail Direct Injection Diesel Engine Research Articles

Effect of Butylated Hydroxytoluene Nanoparticles Blended with Biodiesel Derived from Bauhinia Purpurea Linn Seed Fueled in a CRDI Diesel Engine

This study sought to investigate techniques for lowering diesel engine emissions by using waste seed as an alternative energy source in place of conventional fossil fuels. This study thoroughly investigated the process of transesterifying waste seed oil obtained from Bauhinia purpurea linn for use as fuel in a common rail direct injection (CRDI) diesel engine. Butylated hydroxytoluene (BHT) nanoparticles serve as a combustion enhancer. The engine outcome metrics were analyzed using diesel, Bauhinia purpurea linn biodiesel (BPLB) and BPLB-BHT blends ([Formula: see text]m BHT 10 ppm and [Formula: see text]m BHT 10 ppm) without changing the operating circumstances. At full brake power, the [Formula: see text]m BHT 10 ppm mix outperformed the BPLB and [Formula: see text]m BHT 10 ppm blends, but fell short of diesel. The [Formula: see text]m BHT 10 ppm blend reduced smoke opacity by 39.14%, hydrocarbon (HC) emissions by 42.71%, carbon monoxide (CO) emissions by 59.03% and oxides of nitrogen (NOx) emissions by 12.29% compared to neat diesel fuel at maximum brake power.

Optimization of NOX emissions of a CRDI DIESEL engine using CMA-ES method

Engine calibration is the tuning of embedded parameters in the engine control unit (ECU) software to improve vehicle characteristics and meet legal requirements. Due to the stricter emission limits and rising customer expectations, current ECU software may include variables up to 30,000, which require very much time for engine calibration development. For this reason, automotive manufacturers continuously develop mathematical-based optimization methods to find optimum operating conditions for the engines. This study aimed to develop an online optimization algorithm to conduct automated dynamometer tests in the calibration development process. A modified covariance matrix adaptation (CMA) algorithm, which is an evolutionary strategy (ES) method belonging to meta-heuristic optimization, was integrated with an automation system for online calibration optimization. Some CMA method parameters such as step size and damping factor were initially revised to achieve the method to function efficiently in online engine calibration. Optimization was conducted at three different operating points of a 2-liter common rail direct injection (CRDI) diesel engine, where NOx emission mainly impacts the New European Driving Cycle (NEDC) results. The main injection timing, rail pressure, pilot injection quantity and timing, manifold pressure, and mass air flow were controlled in the optimization process. Optimization targets were determined according to the NOx-PM Pareto curve for each operating point. Covariance matrix adaptation was used to generate Pareto curves. Sixty-five measurements were taken for each operating point in the optimization process. Once optimization targets were determined, optimization occurred at each operating point. A total NOx emission reduction of 3.8% was obtained in the NEDC test, while fuel consumption and PM remained almost the same at steady-state operating points. The modified CMA-ES algorithm is expected to be an efficient method for online calibration optimization.

Effects of Blended Diesel-Biodiesel Fuel on Emissions of a Common Rail Direct Injection Diesel Engine with Different Exhaust Gas Recirculation Rates.

The aim of the study was to investigate the exhaust gas emissions and fuel consumption of a common rail direct injection (CRDI) diesel engine using mixed diesel (B10) and biodiesel (B20-B100) fuels. The study's primary objective was to determine the effects of blended diesel-biodiesel fuel on CRDI emissions based on different exhaust gas recirculation (EGR) rates, including carbon monoxide (CO), carbon dioxide (CO2), oxygen (O2), nitrogen oxide (NOx), and hydrocarbon (HC) emissions, smoke opacity, exhaust gas temperature, and fuel consumption. The CRDI experiments involved adjusting the different engine speeds (1400-3000 rpm) and EGR rates (0 and 12.5%), which were analyzed to determine their impact on these parameters for both blended diesel and biodiesel fuels. The results showed that under the conditions of no EGR (0%), the CO and HC emissions and the smoke opacity were lower than those with a 12.5% EGR rate for all fuel types and all cases. With 12.5% EGR rate, the O2 emissions and the EGT of the CRDI diesel engine decreased, which resulted in significantly lower NOx emissions because of EGR into the combustion chamber. For the maximum engine speed of 3000 rpm and with no EGR, the CO and HC emissions and the smoke opacity were lower than those with a 12.5% EGR rate for all fuel types. With a 12.5% EGR rate at 3000 rpm, the O2 emissions and the exhaust gas temperature were reduced by 0.07% and 2.27%, respectively, and the NOx emissions were reduced by 2.54%. However, with EGR, the CO and HC emissions and the smoke opacity increased by 7.70%, 18.61%, and 0.4%, respectively. Furthermore, the fuel consumption of pure biodiesel (B100) at 3000 rpm with a 12.5% EGR rate was reduced by 2.81% compared to that with a 0% EGR rate. Because the temperature in the combustion chamber is high enough for the engine to run, the EGR reuses a portion of the exhaust gases and can help to minimize the quantity of fuel in the combustion chamber. As a suggestion based on these observations, biodiesel fuel should not exceed B80 because the viscosity and density of fuel that are too high may affect the fuel injection system, both the injectors, and the pressure pump, causing the injectors to be unable to work correctly. These findings can contribute to the development of strategies and technologies for reducing emissions and improving fuel efficiency in CRDI diesel engines.

Screening nano additives for favorable NOx/smoke emissions trade-off in a CRDI diesel engine fueled by industry leather waste fat biodiesel blend

The depletion of petroleum reserves and increasing environmental concerns prompted significant research into alternative fuels. This work, biodiesel, is extracted from the byproduct of industrial leather waste fat to generate beneficial energy.The main objective of this study is to enhance common rail direct injection (CRDI) diesel engine outcome characteristics by substituting industrial leather waste fat biodiesel (ILWFB) with the mixing of aluminium nitrate (Al (NO3)3) nanoparticles and graphene oxide nanoplates (GONPS) in the proportion of 50 ppm (parts per million) as catalysts to enhance ignition process. This research found that with the mixing of Al (NO3)3 nanoparticles and GONPS 50 ppm into the ILWFB blend, the in-cylinder pressure increased by 0.463% and 1.5%, and the heat release rate (HRR) improved by 4.19% and 12.04% than diesel and ILWFB blend at maximum load circumstances. Brake thermal efficiency (BTE) increased by 3.1% and 5.27%, and brake specific fuel consumption (BSFC) decreased by 3.57% and 7.14% in D50ILWFB50+Al (NO3)3 50 ppm blend and D50ILWFB50+GONPS 50 ppm blend related to diesel fuel. The carbon monoxide (CO), hydrocarbon (HC), and smoke emissions were reduced by 26.84%, 13.11%, and 5.75% in D50ILWFB50+Al (NO3)3 50 ppm blend and 38.94%, 21.31%, and 9.12% decreased in D50ILWFB50+GONPS 50 ppm blend than diesel fuel. Oxides of nitrogen (NOx) emissions marginally increased by 3.66%, 5.42%, and 8.94% in ILWFB blend, D50ILWFB50+Al (NO3)3, and D50ILWFB50+GONPSrelated to pure diesel at peak load conditions. This work concluded that the nano additives effectively enhanced BTE and decreased BSFC, CO, HC, and smoke emissions in diesel engine applications.

Studies on CRDI diesel engine performance and emissions using waste plastic oil and fly ash catalyst

Fossil fuels are quickly draining on a daily basis, causing fuel product prices to increase throughout the world. There is a crucial need to develop new alternate fuels from various sources that meet our daily requirements, like industries, mining, building construction, transportation, electric power generation from rural areas, etc. In the present study, mono-use low density polyethylene (LDPE) was successfully transformed into a liquid form of hydrocarbon fuel with fly ash-supported catalytic pyrolysis. The ratio of 0.1 with reference to catalyst-to-feedstock was fixed for the preparation of waste plastic oil (WPO) using batch-type pyrolysis reactors. About 180 °C was the temperature at which the extracted crude oil was segregated. The diesel fuel’s properties and those of the WPO fuel were compared and evaluated. Experiments were carried out using diesel-WPO mixed fuel (10%, 20%, 30%, and 40%) in a multi-cylinder, water-cooled Common Rail Direct Injection (CRDI) diesel engine. Additionally, the impact of the compression and mixing ratios on performance, emission characteristics, and combustion was studied. We observed significant improvement in the results of BTE and BSFC for the tested fuel blend, D80WPO20, compared to other blends. Additionally, it has been demonstrated that the emissions of CO, HC, and NOx rise with an increasing fuel mixing ratio. Based on the analysis carried out on performance and emissions, it was determined that D80WPO20 was the best combination.

Determination of combustion and emission characteristics of liquid Fischer-Tropsch diesel fuel synthesized from coal in a diesel engine

Fischer–Tropsch (FT) synthesis is a production method that processes a liquid diesel fuel from heavy carbon-containing organic compounds such as coal and biomass. FT synthesis is an essential process in demonstrating the usability of coal-to-liquid fuel in internal combustion engines. This study investigates the effects of using FT diesel fuel synthesized from coal on the combustion characteristics of a single-cylinder common-rail direct-injection diesel engine. The engine tests were conducted at 50% of the wide-open throttle position and fixed engine control parameters (cycle duration, fuel amount, start of injection timing, etc.). As a result of the study, it was observed that the combustion with the use of FT diesel fuel started (almost 1.5 °CA) and completed earlier according to the petroleum-based diesel (D100). The cyclic variations were more stable with FT diesel fuel. With the use of FT diesel fuel, the indicated mean effective pressure was 3% lower, peak cylinder gas pressure was slightly lower, and the combustion noise was 2–3 dB quieter compared to D100. The heat release was higher during the premixed combustion phase at the cycle durations of 67 ms and 55 ms, while it occurred very small at the cycle duration of 86 ms. Significant reductions in CO2 and NOx emissions, which are complete oxidation products, were obtained with FT diesel fuel compared to D100. The fuel properties, combustion characteristics and emission results showed that no further measures should be taken to use FT diesel in compression ignition engines. FT diesel fuel can be safely used as an alternative fuel.

Effects on the performance and emission characteristics of CRDI diesel engine fueled with ethanol, acid oil methyl ester biodiesel and diesel blends

The present investigation of utilizing biodiesel as an alternative additive for diesel and ethanol for diesel engines. Biodiesel blended with diesel or ethanol using 50 vol% biodiesel and by varying 04 vol%, 08 vol%, 12 vol% and 16 vol% ethanol with 46 vol%, 42 vol%, 38% vol and 34% vol diesel blend on 4-stroke 4-Cylinder, Common Rail Direct Injection (CRDI) Diesel engine. The experimental results showed that the fuel properties of the blend met the requirements of a diesel engine, although a trend towards more carbon residue was observed with increasing proportion of biodiesel. Studies have shown that with increasing alcohol content in the mixture, brake thermal efficiency decreases, BSFC increases, CO and HC emissions increase while NOx emissions decrease. As the engine speed increased from 1200 to 1800 rpm, BTE continued to increase, but CO and HC emissions decreased, while NOx emissions increased significantly.

Analysis of CRDI diesel engine characteristics operated on dual fuel mode fueled with biodiesel-hydrogen enriched producer gas under the single and multi-injection scheme

The present work aims to investigate the consequences of pilot fuel (PF) multiple injections and hydrogen manifold injection (HMI) on the combustion and tailpipe gas characteristics of a common rail direct injection (CRDI) compression ignition (CI) engine operated on dual fuel (DF) mode. The CI engine can perform on a wide variety of fuels and under high pilot fuel (PF) pressure. Pilot fuel injection (PFI) is achieved at TDC, 5, 10, and 15ºCA before the top dead center (bTDC), and divided injection consists of injecting fuel in three different magnitudes on a time basis and PF is injected into the engine cylinder at a pressure of 600 bar. In this work, the hydrogen flow rate (HFR) was fixed at 8 lpm constant and producer gas was inducted without any restriction. The investigational engine setup has the ability to deliver a PF and hydrogen (H2) precisely in all operating circumstances using a separate electronic control unit (ECU). Results showed that diesel-hydrogen enriched producer gas (HPG) operation at maximum operating conditions provided amplified thermal efficiency by 4.01% with reduced emissions, except NOx levels, compared to biodiesel-HPG operation. Further, DiSOME with the multi-injection strategy of 60 + 20+20 and 50 + 25+25, lowered thermal efficiency by 4.8% and 9.12%, respectively compared to identical fuel combinations under a single injection scheme. However, reductions in NOx levels, cylinder pressure, and HRR were observed with a multi-injection scheme. It is concluded that multi-injection results in lower BTE, changes carbon-based emissions marginally, and decreases cylinder pressure and heat release rate than the traditional fuel injection method.

Experimental evaluation of soapberry seed oil biodiesel performance in CRDI diesel engine

Due to the ongoing demand for alternative fuels for CI engines, biodiesel-based research has received support globally. In this study, soapberry seed oil produced by transesterification process to creates biodiesel. It is referred to as BDSS (Biodiesel of Soapberry Seed). According to criteria, the oil qualities are recognized, hence, three different blends and pure diesel were tested in CRDI (Common Rail Direct Injection) engines. The blends descriptions are: 10BDSS (10% BDSS + 90% diesel), 20BDSS (20% BDSS + 80% diesel), and 30BDSS (30% BDSS + 70% diesel). The outcomes of the related tests for combustion, performance, and pollution were contrasted with those achieved using 100% diesel fuel. In this case, the mixing has resulted in worse braking thermal efficiency than diesel and lower residual emissions with greater NOx emissions. The superior results were obtained by 30BDSS, which had BTE of 27.82%, NOx emissions of 1348 ppm, peak pressure of 78.93 bar, heat release rate (HRR) of 61.15 J/deg, emissions of CO (0.81%), HC (11 ppm), and smoke opacity of 15.38%.

Effective utilization of waste pork fat as a potential alternate fuel in CRDI research diesel engine – Waste reduction and consumption technique

This work utilized the conventional transesterification process to convert waste pork fat into pork fat biodiesel. The produced biodiesel was meant to serve as a diesel fuel substitution for common rail direct injection (CRDI) diesel engines. Butylated Hydroxytoluene (BHT) as an antioxidant doping with waste pork fat biodiesel-diesel blend has not been analyzed in CRDI diesel engines. Therefore, to improve the ignition process and reduce the engine exhaust emissions in a research CRDI diesel engine, the BHT was employed to combine with diesel-biodiesel mixtures in this work. BHT antioxidants are partially mixed (BHT 50, 100, and 150 ppm) to improve the physicochemical qualities of test fuel and enhance the combustion process of diesel-biodiesel blends (B20). The antioxidant purity was analyzed by energy dispersive X-ray analysis (EDX), structures were analyzed by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) analyzer spectrograph was utilized to study the biodiesel chemical components. After mixing the BHT, the overall phase of the base fuel remained constant. The experiment outcomes revealed that the biodiesel had higher cylinder pressure than the other test fuels, and the BHT100 ppm blend had a higher heat release rate (HRR). B20BHT100 blend shows 3.98% higher brake thermal efficiency (BTE) at full load operation than pure biodiesel but lowered to diesel fuel. Biodiesel (B100) decreases the smoke opacity by 4.5% compared to diesel fuel. BHT has been incorporated into the biodiesel blend to minimize oxides of nitrogen (NOx) emissions at all loads. The B20BHT150 blend decreased NOx emissions by 5.06% more than diesel fuel at maximum load. Compared to pure biodiesel, the B20 blends reduce carbon monoxide (CO) emissions by 7.1% and hydrocarbon emission (HC) by 12.5%. This research found that adding BHT to biodiesel blends lowers NOx emissions with a slight impact on performance.

Combustion and Emission Characteristics of a Diesel Engine Fueled with Crude Palm Oil Blends at Various Idling Speeds

At present, the preparation cost of biodiesel is still higher than that of diesel. Thus, directly using vegetable oil before transesterification can greatly reduce the cost. This study investigated the application characteristics of the direct use of crude palm oil (CPO) in a common rail direct injection (CRDI) diesel engine. In this study, the combustion characteristics, engine performance, and emission characteristics of the CRDI diesel engine operated with CPO0 (neat diesel fuel), CPO10 (10% CPO blended with 90% diesel fuel by volume), CPO30 (30% CPO blended with 70% diesel fuel by volume), and CPO50 (50% CPO blended with 50% diesel fuel by volume) at three idling speeds (750 rpm, 1500 rpm, and 2250 rpm) were evaluated. The results obtained from the experiment elucidate that combustion starts earlier by increasing the idling speed. The addition of CPO to diesel fuel resulted in a decrease in the peak in-cylinder pressure at all idle speeds and a decrease in the maximum heat release rate (HRRmax) at 750 and 1500 rpm, but an increase in HRRmax at 2250 rpm. On the other hand, increasing idle speed is beneficial for reducing carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx), but it increases smoke emissions. In addition, adding 10% and 30% CPO to diesel fuel can reduce both HC, NOx, and smoke emissions simultaneously.

Effect of injection timing on combustion, emission and particle morphology of an old diesel engine fueled with ternary blends at low idling operations

Currently, idling emissions and old vehicle emissions have attracted more and more attention. Many countries have made corresponding policies to limit these emissions. In this study, to investigate the combustion, engine performance, and emission characteristics of an old diesel engine fueled with diesel-palm biodiesel-ethanol (DPE) ternary blended fuels according to various multiple injection strategies under low idling conditions, a series of experiments were carried out on an old common-rail direct injection (CRDI) diesel engine. The engine speed and load were fixed at 750 rpm (the lowest speed) and 30 Nm, respectively. Two test modes of A (only pilot injection timing was variable) and B (only main injection timing was variable) were comparative studied. The experimental results show that the main-pilot injection timings and DPE ternary blends have significant impacts on the engine performance, combustion and characteristics. Overall, as the ethanol concentrations in DPE ternary blends increase, brake specific fuel consumption (BSFC), maximum heat release rate (HRRmax), ignition delay, carbon monoxide (CO) and hydrocarbon (HC) emissions increase, while nitrogen oxides (NOx) and smoke emissions are simultaneously reduced. The high volatility, high latent heat of evaporation and high oxygen content of ethanol may play a major role in reducing NOx and smoke emissions. In addition, the primary particle diameter of all tested fuels is distributed in a narrow range of 18–24 nm, and the addition of ethanol is beneficial to reduce the particle diameter.

An experimental study on biodiesel production and impact of EGR in a CRDI diesel engine propelled with leather industry waste fat biodiesel

The purpose of the predominant endeavor is the way of through an experiment aspect for the reticular effect of exhaust gas recirculation (EGR) on combustion, performance, emissions besides energy characteristic of common rail direct injection (CRDI) engine fuelled with leather industry waste fat biodiesel and diesel blends. Biodiesel was converted by the transesterification process from the raw fat oil extracted with leather waste fat feedstock. This work takes advantage of blends of both like B10, B20, B30 along with engines that were run with various EGR rates (5%, 10%, and 15%) to evaluate engine outcome parameters. The maximum in-cylinder pressure was examined with the blend B20 with EGR 5% rate about 6.65% higher than pure diesel fuel. The high heat release rate (HRR) was ascertained with the blend B30 with EGR 10% rate about 23.81% higher than neat diesel fuel. The brake thermal efficiency (BTE) for the blend B10 with EGR 5% rate is higher than other test conditions but 4.2% let down associated with simple diesel fuel. The nitrogen oxides (NOx) were lesser than the clean diesel fuel at all test fuels, the highest NOx emission reduction was achieved in blend B30 with EGR 15% rate of about 87.59% than neat diesel fuel operation. The smoke opacity increased by raising the EGR level, the combination B30 with EGR 5% rate displayed low smoke opacity about 64.5% lower than neat diesel fuel. The hydrocarbon (HC) emission was lower than neat diesel at a low EGR rate, the blend B10 with EGR 5% rate displayed the lowest HC emission about 85.71% decreased then neat diesel operation. The carbon monoxide (CO) emission displayed lower than neat diesel at low EGR rate, the blend B10 with EGR 5% rate displayed the lowest CO emission about 50% than neat diesel. As of energy analysis, it was noted that the heat equivalent to brake power and heat lost to engine cooling water is higher in diesel fuel than biodiesel blends and the heat lost to exhaust gases and heat unaccounted loss were lower in diesel than biodiesel blend. Finally, the TOPSIS optimization study was carried out for finding the optimum input conditions which could result in improved combustion, performance, and reduced emissions. The B30% blend with EGR 15% at full load achieved 1st rank with 0.849 relative closeness value. So, this operating condition was projected as the best prospect for the application of a CRDI diesel engine.

Wavelet analysis for cyclic combustion dynamics of a multi-cylinder CRDI diesel engine fuelled with a blending of argemone biodiesel-diesel oil.

Higher cyclic variability in combustion adversely influences emissions, efficiency, and driveability of internal combustion engines. In this paper, we used wavelet transform techniques to investigate the dynamical characteristics of a combustion process in numerous combustion parameters of a 4-cylinder turbocharged common rail direct injection (CRDI) diesel engine fuelled with Argemone mexicana biodiesel (AGB)/diesel blended fuel. In addition, statistical analysis is described to validate the results of the wavelet spectrum methods for cyclic variation in the diesel engine. The results show that the cyclic variations in IMEP and Pmax are sensitive to the engine load and fuel properties. The coefficient of variation of both combustion parameters decreases as engine load increases for all tested fuels. Moreover, adding Argemone mexicana biodiesel (AGB) into diesel fuel up to 20% (AB20) reduces cyclic variations in combustion parameters at all tested engine loads. Furthermore, the global wavelet spectrum and wavelet power spectrum are utilized to identify the dominant oscillatory combustion modes. The cycle-to-cycle fluctuations in combustion parameters (i.e., IMEP and Pmax) exhibit multi-scale dynamics for all experimental conditions. Compared to long and intermediate oscillations in diesel fuel, AB10 and AB20 fuel showed short and intermittent period fluctuations. The findings of this experimental work will be helpful to optimize engine control strategies for AGB/diesel blended fueled multi-cylinder CRDI diesel engines.

Multi-objective optimization of performance and emission characteristics of a CRDI diesel engine fueled with sapota methyl ester/diesel blends

This study examines the combined effect of compression ratio (CR) and exhaust gas recirculation (EGR) on combustion, performance, and emissions characteristic of a common rail direct injection (CRDI) engine fueled by sapota methyl ester (SME) and diesel blend. Biodiesel extracted from sapota fruits waste seeds through the transesterification process. This work utilised diesel-biodiesel blend B50% blend (D50SME50 by vol.), and the engine was run with different compression ratios (16, 17.5, and 19) and EGR rates (0%, 10%, and 20%) to evaluate engine outcome parameters. The result found that the ignition delay was reduced with an increased compression ratio. The high heat release rate (HRR) was ascertained with the CR 16 and EGR 10% rate, about 6.01% higher than diesel fuel. The highest in-cylinder pressure was observed with the CR 19 and EGR 0% rate, about 2.02% higher than diesel. The thermal brake efficiency (BTE) for CR 16 and EGR, 0% rate, is higher than other test conditions but 11.21% lower than neat diesel. The nitrogen (NOx) emission oxides for all the test conditions were lower than neat diesel. The highest NOx emission reduction was achieved in CR 16, and EGR 20% rate about 61.91% lower than diesel operation. The smoke opacity increased by increasing the EGR rate. The CR 17.5 and EGR 0% rate displayed lower smoke opacity, about 2.5% lower than diesel operation. The hydrocarbon (HC) emission was lower than neat diesel at all operating parameters. The CR 17.5 and EGR, 0% rate, displayed the lowest HC emission, about 44.82% decreased than neat diesel operation. The carbon monoxide (CO) emission displayed lower for the EGR 0% rate at all the compression ratios. The CR 16 and EGR 0% rate displayed the lowest HC emission, about 10.77%, than diesel operation. The energy analysis noted that the fuel energy input and energy for brake power and energy flown through the exhaust gases are higher in diesel fuel than biodiesel blend. The unaccounted losses were low in diesel than biodiesel blend. Finally, the TOPSIS optimization study was carried out to find the optimum input conditions to improve combustion, performance, energy, and reduced emissions. The B50% blend with CR 16 and EGR 20% at full load achieved 1st rank with 0.809 relative closeness value. So, this operating condition was projected as the best prospect for applying in a CRDI diesel engine.

NOx–Smoke Trade-off Characteristics in a Palm Oil-Fueled CRDI Diesel Engine under Various Injection Pressures and EGR Rates

Palm oil is one of the most common and productive vegetable oils, so it is often used as an excellent feedstock for biodiesel production. However, due to the high viscosity and other issues of palm oil, it cannot be directly used as an alternative fuel for diesel engines unless some treatment is carried out. In this study, the effects of palm oil-diesel blend fuel on the nitrogen oxides (NOx)–smoke trade-off characteristics were investigated in a common rail direct injection (CRDI) diesel engine under various injection pressures and exhaust gas recirculation (EGR) rates. It was found that NOx and smoke from the combustion of fuel containing 50% palm oil (P50D50) were simultaneously suppressed by 3% and 3.1% compared with diesel fuel at an injection pressure of 400 bar, respectively. The performance of P50D50 was comparable to that of diesel, but at high injection pressure and high EGR rate, it showed shorter ignition delay (ID) and lower smoke emission.

Assessment of The Impact of Multiple Injection Strategies on Combustion Noise, Smoke and Performance Characteristics of a CRDI Heavy Diesel Engine

This experimental research paper presents the impact of 5 different multiple injection strategies as 2-double comprising pilot-Main (pM), Main-after (Ma), 2-triple comprising pilot-Main-after (pMa), early-pilot-Main (epM) and quadruple comprising early-pilot-Main-after (epMa) in comparison with single injection on combustion noise (CN), Brake Specific Fuel Consumption (BSFC), Torque, Brake Thermal Efficiency (BTE) and Smoke emissions. The experimental evaluation was carried out on a 6-cylinder inline CRDI (Common rail Direct Injection) diesel engine in low temperature combustion (LTC) regime with high EGR of 45%, and fixed main injection Crank Angle (CA) using conventional diesel (BS-IV) fuel at full load and 8 speeds (low to high). The comprehensive study revealed that quadruple (epMa) injection strategy is superior in providing optimum results in comparison to other 4 multiple injection strategies in line to single injection. This strategy displayed better BSFC at medium to high speeds zone inline to reduce of combustion noise (radiated) level especially at low speeds around 2 dBA. The epMa exhibited the 2nd best smoke/soot concentration whereas pMa injection scheduling is best in lower smoke/soot generation. The epMa was found to be an optimum in torque performance though epM showed best torque performance in low to medium speed zone. The epMa showed the best BTE than all other. This work indicates the potentiality and further scope to achieve better performance and emissions simultaneously with quadruple injection strategy by parametric optimization of injection parameters.

Energy, exergy, thermoeconomic and sustainability assessment of tire pyrolysis oil in common rail direct injection diesel engine

Waste to fuel conversion has attracted prominence due to higher fuel demand, waste disposal issues, and environmental and economic impact. Therefore, an alternative approach for addressing the issue of waste tire disposal can be provided by using tire pyrolysis oil (TPO). The energy, exergy, thermoeconomic and sustainability studies of TPO-diesel blends were carried out in this study. The analysis was compared with biodiesel-diesel blended fuel and pure diesel. DP10 (Diesel 90%-TPO 10%), DB10 (Diesel 90%-Biodiesel 10%), and neat diesel are used in the experimental study. The four-cylinder diesel engine was used to perform the experiments at different crankshaft speeds ranges 1000–3500 rpm with the increment of 500 rpm. The results reveal that at 3000 rpm, DP10 shows the highest energy and exergy efficiency, 37.12% and 39.60%, respectively, compared to DB10 and D100. The thermoeconomic study indicates that DP10 produced the lowest energy and exergy losses compared to DB10 and D100. The DP10 provides the highest sustainability index, demonstrating that the DP10 is the most sustainable fuel compared to D100 and DB10. It is concluded that the DP10 shows the best results, and it is appropriate to use in the turbocharged common-rail direct injection diesel engine.

Potential improvement in conventional diesel combustion mode on a common rail direct injection diesel engine with PODE/WCO blend as a high reactive fuel to achieve effective Soot-NOx trade-off

Many countries in and around the world have conducted various studies on biodiesel usage over common rail direct injection (CRDI) diesel engines, among which waste cooking oil (WCO) biodiesel has made a major impact on diesel engine research because of its cost-efficient nature and elimination of waste disposal. The deposits of carbon and very high viscosity are some of the key factors which deteriorate the usage of raw WCO biodiesel. Lower volume proportionate blends of WCO biodiesel produce excellent combustion characteristics reducing hydrocarbon (HC), carbon mono oxide (CO), and soot emissions, but they seem to promote the formation of nitrous oxides (NOx). As a solution to overcome this problem, polyoxymethylene dimethyl ether (PODE) with lower viscosity, higher oxygen content, high cetane number, showing better combustion characteristics with a good soot-NOx trade-off is selected for the present research work. The novelty of the current research work shows the reduction of soot and NOx emissions using PODE/WCO/Diesel blends by varying the proportions in a conventional combustion mode of a CRDI diesel engine without any modifications which was lagging by the previous researches. A trans-esterified WCO biodiesel is blended with diesel in varying volumes as 10, 20, and 30%. The chemical properties of the blend fuels were determined using ASTM standards. The investigation was carried out and it was found that W20 blend fuel showed a highest reduction of 21.11%, 23.51%, and 22.45% of CO, HC, and soot emissions respectively with a rise of 6.39% of NOx emissions. W20 blend with a good soot-NOx trade-off was selected in which PODE was blended in varying proportions such as 10, 20, and 30% respectively. The properties of the test fuels were determined and the further investigation was carried out. This second stage of reduction was done in determining the fuel with excellent soot-NOx trade-off without compromising the performance of the engine. It was found that W20P20 blend fuel showed the highest reduction of 33.86%, 50.78%, and 80.86% of HC, CO, and Soot emissions with a slight increase of 0.78% of NOx emissions. Brake Thermal Efficiency was found better for W20P20 fuel in comparison with W20 fuel. Thus, two stages of reduction in emissions were carried out with the aim of meeting the stringent emissions norms in the conventional diesel combustion technique.

Energy-Saving and Pollution-Reduction Potential Analysis for Diesel Engines Fueled with Fischer-Tropsch Fuel.

Alternative fuels have attracted wide attention owing to the increasing energy consumption and environmental pollution problems, which are caused by the extensive application of diesel engines for various occasions. The Fischer–Tropsch (F–T) diesel synthesized from coal is considered as one kind of ideal alternative fuel for diesel engines; however, its combustion and exhaust emission characteristics are different from those of national diesel owing to its special fuel properties. Therefore, the combustion and emission characteristics of F–T diesel and 0# diesel, which meet the China stage VI were compared in a common rail direct injection (CRDI) diesel engine. Moreover, energy-saving and pollution-reduction potential were analyzed in one CRDI diesel engine fueled with F–T diesel. The results showed that F–T diesel had an earlier ignition point, shorter ignition delay, lower cylinder pressure, and heat release rate compared with those of 0# diesel at the same operating conditions. Meanwhile, the amplitude, oscillation level, and energy of cylinder pressure were decreased to some extent, with the maximum drops of 0.98 bar, 16.4 dB, and 1.01 × 1012 Pa, respectively. Additionally, under external characteristic conditions, maximum break thermal efficiency (BTE) and break-specific fuel consumption (BSFC) of F–T diesel were reduced by 1.1 and 2.1% on average compared with those of 0# diesel. In addition, CO, HC, NOx, and SOOT emissions of F–T diesel were found to be lower than those of 0# diesel, which were decreased by an average of 8, 3.7, 2.1, and 1.3%, respectively.