Injector Opening Pressure Research Articles

Effects of injection timing, injector opening pressure and nozzle geometry on the performance of cottonseed oil methyl ester-fuelled diesel engine

Increasing petroleum prices, increasing threat to the environment from exhaust emissions and global warming have generated intense international interest in developing renewable and alternative non-petroleum fuels for engines. Evolving technology and a recurring energy crisis necessitates a continuous investigation into the search for sustainable and clean-burning renewable fuels. In this paper, cottonseed oil methyl ester (COME) was used in a four-stroke, single-cylinder variable compression ratio diesel engine. Tests were carried out to study the effects of fuel injection timing, fuel injector opening pressure (IOP) and injector nozzle geometry on the performance and combustion of COME biodiesel fuel used in a compression ignition engine with a single fuel mode. Fuel injection timing varied from 19° to 27° before top dead centre (bTDC) in incremental steps of 4° bTDC; fuel IOP varied from 210 to 240 bar in incremental steps of 10 bar. Fuel nozzle injectors with three, four and five holes, each of 0.3 mm size, were selected for the study. The results suggested that with retarded injection timing of 19° bTDC, increased IOP of 230 bar and a four-hole nozzle injector of 0.3 mm size resulted in overall better engine performance with an increased brake thermal efficiency and reduced HC, CO and smoke emission levels.

Performance Evaluation of a Low Heat Rejection Diesel Engine with Jatropha Oil

Investigations were carried out to evaluate the performance of a low heat rejection (LHR) diesel engine consisting of air gap insulated piston with 3-mm air gap, with superni (an alloy of nickel) crown, air gap insulated liner with superni insert and ceramic coated cylinder head with different operating conditions of crude jatropha oil (CJO) with varied injection timing and injector opening pressure . Performance parameters [brake thermal efficiency, exhaust gas temperature, coolant load and volumetric efficienc and exhaust emissions [smoke and oxides of nitroge were determined at various values of brake mean effective pressure (BMEP). Combustion characteristics [ peak pressure, time of occurrence of peak pressure and maximum rate of pressure ris of the engine were at peak load operation of the engine. Conventional engine (CE) showed deteriorated performance, while LHR engine showed improved performance with vegetable operation at recommended injection timing and pressure. The performance of both versions of the engine improved with advanced injection timing and higher injector opening pressure when compared with CE with pure diesel operation. Relatively, peak brake thermal efficiency increased by 14%, smoke levels decreased by 27% and NOx levels increased by 49% with vegetable oil operation on LHR engine at its optimum injection timing, when compared with pure diesel operation on CE at manufacturers recommended injection timing.

Optimization of Injection System Parameters and Exhaust Gas Recirculation for Jatropha Biodiesel Fuel in Diesel Engine Using Taguchi Method

AbstractAn experimental investigation and Taguchi optimization analysis were carried out to optimize Jatropha biodiesel engine parameters for lower fuel consumption and exhaust emissions. The engine parameters considered for optimization were injection timing, injector opening pressure, nozzle configuration, nozzle tip protrusion, percentage of exhaust gas recirculation, fuel type, brake mean effective pressure (BMEP), and speed. Taguchi’s signal-to-noise ratio approach was applied to obtain an optimal level setting of these parameters. From the experimental results and further analysis it is concluded that under 95% confidence interval a nozzle configuration of 5×0.18, tip protrusion of 3.5 mm, exhaust gas recirculation of 0%, BMEP of 3.2 bar, and speed of 1,800 rpm with Jatropha biodiesel fuel gave the minimum carbon monoxide (CO) and unburned hydrocarbon (HC) emissions, whereas the lowest nitric oxide (NO) emissions were obtained with an injection timing of 350 crank angle degrees (CAD), nozzle configu...

Effect of injection timing, injector opening pressure and nozzle geometry on the performance of a compression ignition engine operated on non-edible oil methyl esters from different sources

Increasing cost of fossil fuels, environmental threats from exhaust emissions and their depleting nature have generated intense international interest in developing renewable and alternative fuels for internal combustion engines. This study investigates the suitability of different non-edible-derived biodiesels such as cottonseed oil methyl ester (COME), honne oil methyl ester (HnOME) and honge oil methyl ester (HOME) to four-stroke, single-cylinder compression ignition (CI) engine. Engine tests were conducted to study the effect of fuel injection timing (IT), fuel injector opening pressure (IOP) and injector nozzle geometry on the performance, combustion and emission characteristics of COME, HnOME and HOME in the modified CI engine. IT was varied from 19° to 27° before top dead centre (bTDC) in steps of 4° bTDC; IOP was varied from 205 to 240 bar in steps of 10 bar. Nozzle injectors of three to five holes, each of 0.3 mm size, were selected for the study. It was concluded that a retarded IT of 19° bTDC increased IOP of 230 bar, and four-hole nozzle injector of 0.3 mm size resulted in overall better engine performance with increased brake thermal efficiency and reduced hydrocarbon and carbon monoxide smoke emissions for the fuels tested.

Correlation analysis of factors influencing the electronic unit pump cycle fuel injection quantity under overall operating conditions for diesel engines

Electronic unit pump (EUP) can satisfy both diesel engine emission legislation and fuel economy by improving injection pressure and numerical control. Fluctuations in cycle fuel injection quantity (CFIQ) of EUP determine the coherence and stability of the EUP fuel injection system. The EUP simulation model is developed in the AMESim environment. The method for the simulation experiment is designed in the MODDE environment using the design of experiments method. The results of the simulation reveal the variation laws of correlation between parameters with interaction or no interaction under overall operating conditions of diesel engines. In addition, the results also show the EUP system is a complex nonlinear system. Under overall operating conditions, all the characteristic parameters, such as fuel supply pressure, cam profile velocity, control valve lift, injector opening pressure, injector needle lift, and injector flow coefficient, have significant correlation with CFIQ. The interacting first-order factors exhibit the most significant correlation with CFIQ. The self-interacting second-order factors have significant secondary correlation with CFIQ.

Blends of karanja and jatropha biodiesels for diesel engine applications

Over a number of years, the work of exploring different biodiesels as an alternative to diesel fuel has been carried out worldwide. Not much focus on the use of combination of different biodiesels and their behaviour in diesel engines has been reported. This work is an attempt in this direction, which reports on the use of combination of biodiesels derived from jatropha and karanja oils. Jatropha oil methyl ester (JOME) and honge oil methyl ester (HOME) represent the respective biodiesels derived from these non-edible oils. Experiments were conducted on a four-stroke, single-cylinder diesel engine using these biodiesel combinations in order to check their feasibility as alternative fuels to diesel. Initially, experiments were conducted on each biodiesel and their blends with diesel and engine parameters were optimised in terms of injection pressure and injection timing. Advancing the injection timing improved the overall performance of the engine fuelled with JOME while retarding the injection timing favoured the HOME. Both biodiesels performed better with an injector opening pressure of 230 bar. Finally, experiments were conducted with the combination of both biodiesels with different blend ratios. It was observed that increasing the JOME content in the biodiesels blend improved the performance with reduced emissions of smoke, hydrocarbons and carbon monoxide emissions. However NO x emission increased.

A study on cycle fuel injection quantity variation for a diesel engine combination electronic unit pump system

A new fuel injection equipment, combination electronic unit pump was developed to make diesel engines compliant with China’s new laws on emissions. Combination electronic unit pump system is a complex assembly constituting of mechanical, hydraulic, and electrical magnetic components. Combination electronic unit pump system includes several electronic unit pumps and mechanical injectors. Cycle fuel injection quantity variation influences product performance and defines its quality of qualification. A numerical model of the combination electronic unit pump system was developed in AMESim environment to create a design tool for engine application and system optimization. Simulated results obtained from this numerical model were validated through experimental tests conducted under the conditions same as numerical model. The results are quite encouraging and consistent with model predictions. Influences of parameters, including variations in supply fuel pressure, cam velocity, plunger-matching clearance, peak control current, anchor residual clearance, valve-matching clearance, valve lift, injector opening pressure, nozzle-flow coefficient, and injector needle lift, on cycle fuel injection quantity variation were analyzed in AMESim simulation environment and verified through experiments. The quantitative percentage indexes of the influence of injector characteristic, valve characteristic, plunger characteristic, and low-pressure supply fuel characteristic parameters on cycle fuel injection quantity variation range from 44% to 34%, 20% to 35%, 32% to 19%, and 4% to 12%, respectively, at a cam rotational speed of 500–1300 r/min.

PXI-Based High Performance Data Acquisition System for Fuel Injection System of Diesel Engine

High-performance data acquisition system is designed on the foundation of studying the working principle of diesel engine fuel injection system and analyzing the characteristics of fuel injection pressure waveform. The fuel injection pressure waveform can be accurately captured by the data acquisition system which based on embedded pressure sensors and NI PXI-6143 multifunction data acquisition card, and then the fuel injection opening pressure and the maximum injection pressure can be calculated. Fuel supply advance angle can be obtained by comparing the injection pressure waveform and the top dead center signal. The signal to noise ratio of the data acquisition system is very high, and the operating parameters of fuel supply system can be calculated without software filter. The fuel injection opening pressure, maximum injection pressure and fuel supply advance angle were obtained in situ test on 6L20/27 diesel. The operating parameters all coincide with the technology data sheet given by the factory.

Effect of injector opening pressure on performance, emission and combustion characteristics of DI diesel engine fueled with diesel and honne oil methyl ester

Honne oil methyl ester (HOME), a nonedible vegetable oil has remained as an untapped new possible source of alternative fuel. The present research is aimed to investigate experimentally the performance, exhaust emission, and combustion characteristics of a DI diesel engine, when fueled with neat diesel (ND) and HOME. The injector opening pressure (IOP) is varied from 200 bar (manufacturer specified value) to 260 bar in steps of 20 bar.The combustion parameters of HOME (IOP 260 bar) are found to be very close to ND. For other IOPs, these combustion parameters deviated compared to ND. The performance (BTE, BSFC, and EGT) of HOME (IOP 260 bar) is almost the same as that of ND. For other IOPs, BTE is inferior compared to ND. The emissions (CO and SO) of HOME (IOP 260 bar) are dropped significantly compared to ND. HC emissions of HOME (IOP 240 bar) are slightly decreased, whereas for other IOPs, it is increased compared to ND. NOx emissions of HOME (IOP 200 to 260 bar) are slightly decreased.The reductions in exhaust emissions and increase in BTEmade HOME (IOP 260 bar) a suitable alternative fuel for diesel fuel and thus could help in controlling air pollution. © 2011 American Institute of Chemical Engineers Environ Prog, 32: 148–155, 2013.

Effect of injection pressure on diesel engine performance with Sea lemon oil

Due to the increasing demand for fossil fuels and environmental threat, a number of renewable sources of energy have been studied worldwide. An attempt is made to assess the suitability of vegetable oil for diesel engine operation, without any modifications in its existing construction. One of the important factors which influence the performance and emission of diesel engine is fuel injection pressure. In the present investigation a vegetable oil, Sea lemon oil has been investigated in a constant speed, DI diesel engine with varied fuel injection pressures (170, 190,210 and 230 bar). The main objective of this study is to investigate the effect of injection pressures on performance and emissions characteristics of the engine. The injection pressure was changed by adjusting the fuel injector spring tension. The performance and emission characteristics were presented graphically and concluded that increase in injector opening pressure increases the brake thermal efficiency and reduces unburned hydrocarbon and smoke emissions significantly.

Effect of Injection Time and Injection Pressure on CI Engine Fuelled with Methyl Ester of Thevetia Peruviana Seed Oil

Fast depletion of the fossil fuels and stringent emission norms direct us to search for some alternative fuel which can reduce our dependence on fossil fuels. Vegetable oil is a promising alternative fuel for CI engine because it is renewable, environment friendly, and can be produced easily in rural areas. The use of non-edible vegetable oils when compared with edible oils is very significant in developing countries. In this direction, it has already been proved that thevetia peruviana seed oil can be a good alternative fuel for CI engine. In this study, an attempt has been made to study the effect of injection timing and injection pressure on diesel engine fuelled with methyl ester of thevetia peruviana seed oil. A fully automated, single cylinder, constant speed, direct injection diesel engine was operated with the methyl ester of thevetia peruviana seed oil. Advancing the injection timing from the base diesel value and increasing the injector opening pressure has been found to increase the brake's thermal efficiency and reduce CO, HC and smoke emissions significantly. Also, optimum injection time and injection pressure were found as 27° before TDC and 225 bar respectively.

Effect of injector opening pressures on the performance, emission and combustion characteristics of DI diesel engine running on honne oil and diesel fuel blend

The present work examines the use of a non-edible vegetable oil namely honne oil, a new possible source of alternative fuel for diesel engine. Highly viscous honne oil can be reduced by blending it with diesel fuel. A direct injection diesel engine typically used in agricultural sector was operated on neat diesel and a blend of 50% honne oil with 50% diesel fuel (H50). Injector opening pressure was changed to study the performance, emission and combustion characteristics. It was observed that increasing the injector opening pressure with H50 from the rated injector opening pressure (200 bar) increased the brake thermal efficiency and reduced CO, HC, and smoke opacity emissions. However, NOx emission was increased. With H50, ignition delay decreased as injector opening pressure increased. Improved premixed heat release rate were observed with H50 when the injector opening pressure was advanced. The best injector opening pressure was 240 bar for H50 based on brake thermal efficiency and emissions.

Optimization of Injection System Parameters and EGR on Jatropha Biodiesel Engine using Taguchi Approach

The diesel engine injection system parameters apart from the operating parameters such as load and speed significantly affect its performance and exhaust emissions. The effect is even adverse sometimes when the engine is tried with some alternative fuels, such as Jatropha biodiesel due to its physico-chemical properties. For better performance and to meet out stringent emission norms, these parameters have to be optimized. An experimental investigation and analysis carried out to simultaneously optimize injection system parameters and exhaust gas recirculation (EGR) levels of small direct injection diesel engine for lower fuel consumption and higher thermal efficiency and peak cylinder pressure is presented in this paper. During the experiments, the different parameters such as fuel type, injection timing, injector opening pressure, nozzle configuration, nozzle tip protrusion, percentage of exhaust gas recirculation (EGR), load torque and speed were changed. Taguchi's signal-to-noise ratio approach was applied to obtain an optimal setting of these parameters. From the experimental results and further analysis it is concluded that under 95% confidence interval the injection timing 340°CA, injector opening pressure 250 bar, nozzle configuration 5x0.18, EGR 0%, load torque 15Nm, speed 1800rpm with Jatropha biodiesel, gave the maximum peak cylinder pressure, while the lowest BSFC with diesel fuel was obtained with nozzle configuration 4x0.18, load torque 15Nm and speed 1800rpm and the highest brake thermal efficiency with nozzle configuration 4x0.18, tip protrusion 2mm, load torque 15Nm and speed 1800rpm. However, the significant control parameters responsible for brake thermal efficiency with their percentage contribution were load torque (79.13%), speed (17.54%), nozzle configuration (1.33%) and tip protrusion (0.96%).

Combustion characteristics of diesel engine operating on jatropha oil methyl ester

Fuel crisis because of dramatic increase in vehicular population and environmental concerns have renewed interest of scientific community to look for alternative fuels of bio-origin such as vegetable oils. Vegetable oils can be produced from forests, vegetable oil crops, and oil bearing biomass materials. Non-edible vegetable oils such as jatropha oil, linseed oil, mahua oil, rice bran oil, karanji oil, etc., are potentially effective diesel substitute. Vegetable oils have reasonable energy content. Biodiesel can be used in its pure form or can be blended with diesel to form different blends. It can be used in diesel engines with very little or no engine modifications. This is because it has combustion characteristics similar to petroleum diesel. The current paper reports a study carried out to investigate the combustion, performance and emission characteristics of jatropha oil methyl ester and its blend B20 (80% petroleum diesel and 20% jatropha oil methyl ester) and diesel fuel on a single-cylinder, four-stroke, direct injections, water cooled diesel engine. This study gives the comparative measures of brake thermal efficiency, brake specific energy consumption, smoke opacity, HC, NOx, ignition delay, cylinder peak pressure, and peak heat release rates. The engine performance in terms of higher thermal efficiency and lower emissions of blend B20 fuel operation was observed and compared with jatropha oil methyl ester and petroleum diesel fuel for injection timing of 20° bTDC, 23° bTDC and 26° bTDC at injection opening pressure of 220 bar.

Artificial neural network modeling of jatropha oil fueled diesel engine for emission predictions

This paper deals with artificial neural network modeling of diesel engine fueled with jatropha oil to predict the unburned hydrocarbons, smoke, and NOx emissions. The experimental data from the literature have been used as the data base for the proposed neural network model development. For training the networks, the injection timing, injector opening pressure, plunger diameter, and engine load are used as the input layer. The outputs are hydrocarbons, smoke, and NOx emissions. The feed forward back propagation learning algorithms with two hidden layers are used in the networks. For each output a different network is developed with required topology. The artificial neural network models for hydrocarbons, smoke, and NOx emissions gave R2 values of 0.9976, 0.9976, and 0.9984 and mean percent errors of smaller than 2.7603, 4.9524, and 3.1136, respectively, for training data sets, while the R2 values of 0.9904, 0.9904, and 0.9942, and mean percent errors of smaller than 6.5557, 6.1072, and 4.4682, respectively, for testing data sets. The best linear fit of regression to the artificial neural network models of hydrocarbons, smoke, and NOx emissions gave the correlation coefficient values of 0.98, 0.995, and 0.997, respectively.

Evaluation of hazelnut kernel oil of Turkish origin as alternative fuel in diesel engines

In the present study, hazelnut kernel oil of Turkish origin was evaluated as alternative fuel in a diesel engine. Potential hazelnut production throughout the world and the status of Turkey were examined. Hazelnut (Corylus avellana L.) kernel oil was transesterified with methanol using potassium hydroxide as catalyst to obtain hazelnut kernel oil methyl ester (HOME) and a comprehensive experimental investigation was carried out to examine performance and emissions of a direct injection diesel engine running with HOME and its blends with diesel fuel. Experimental parameters included the percentage of HOME in the blend, engine load, injection timing, compression ratio, and injector. The cost analysis of HOME production comparing to the price of conventional diesel fuel was performed for last decade was performed. Results showed that HOME and its blends with diesel fuel are generally comparable to diesel fuel and small modifications such as increasing injection timing, compression ratio and injector opening pressure provide significant improvement in performance and emissions. It is also expected that the price of HOME will be lower than the price of conventional diesel fuel in the near future.

Combustion and emission characteristics of a dual fuel engine operated with mahua oil and liquefied petroleum gas

For the present work, a single cylinder diesel engine was modified to work in dual fuel mode. To study the feasibility of using methyl ester of mahua oil as pilot fuel, it was used as pilot fuel and liquefied petroleum gas was used as primary fuel. In dual fuel mode, pilot fuel quantity and injector opening pressure are the few variables, which affect the performance and emission of dual fuel engine. Hence, in the present work, pilot fuel quantity and injector opening pressure were varied. From the test results, it was observed that the pilot fuel quantity of 5 mg per cycle and injector opening pressure of 200 bar results in higher brake thermal efficiency. Also the exhaust emissions such as smoke, unburnt hydrocarbon and carbon monoxide are lower than other pressures and pilot fuel quantities. The higher injection pressure and proper pilot fuel quantity might have resulted in better atomization, penetration of methyl ester of mahua oil and better combustion of fuel.

Analysis of energy release and NO x emissions of a CI engine fuelled on diesel and DME

Combustion and NO x emissions from a dimethyl ether (DME) fuelled compression ignition engine were investigated. The test engine used consisted of an unmodified two-cylinder direct injection four-stroke air cooled type. The injection timing and injector opening pressure were left unaltered from their diesel fuelling settings. Analysis of the fuel line pressure shows that due to the compressibility of DME the rate of pressure rise was lower, resulting in injection occurring later when compared to diesel injection. The maximum combustion chamber pressure was found to be higher in the case of diesel fuelling. In terms of energy release it was found that with DME this occurs later than in the case of diesel fuelling with the larger proportion occurring just after top dead centre. A comparison of NO x emissions revealed that, at all loads tested, these were higher in the case of DME fuelling and decreased steadily with increasing speed. At the higher speeds however, the levels of NO x monitored were noted to be less than those of their diesel counterpart. Some of the factors influencing the promotion of NO x emissions with DME fuelling are discussed and analysed.

Parametric studies for improving the performance of a Jatropha oil-fuelled compression ignition engine

A single cylinder, constant speed, direct injection diesel engine was operated on neat Jatropha oil. Injection timing, injector opening pressure, injection rate and air swirl level were changed to study their influence on performance, emissions and combustion. Results have been compared with neat diesel operation. The injection timing was varied by changing the position of the fuel injection pump with respect to the cam and injection rate was varied by changing the diameter of the plunger of the fuel injection pump. A properly oriented masked inlet valve was employed to enhance the air swirl level. Advancing the injection timing from the base diesel value and increasing the injector opening pressure increase the brake thermal efficiency and reduce HC and smoke emissions significantly. Enhancing the swirl has only a small effect on emissions. The ignition delay with Jatropha oil is always higher than that of diesel under similar conditions. Improved premixed heat release rates were observed with Jatropha oil when the injector opening pressure is enhanced. When the injection timing is retarded with enhanced injection rate, a significant improvement in performance and emissions was noticed. In this case emissions with Jatropha oil are even lower than diesel. At full output, the HC emission level is 532 ppm with Jatropha oil as against 798 ppm with diesel. NO level and smoke with Jatropha oil are, respectively 1162.5 ppm and 2 BSU while they are 1760 ppm and 2.7 BSU with diesel.