scholarly journals The influence of the hydrogen injection timing on the IC engine working cycle

2020 ◽  
pp. 346-346
Author(s):  
Ivan Grujic ◽  
Jovan Doric ◽  
Oday Abdullah ◽  
Nadica Stojanovic ◽  
Aleksandar Davinic
Keyword(s):  
Diesel Engine ◽  
Pressure Rise ◽  
Maximum Pressure ◽  
Injection Timing ◽  
Ic Engine ◽  
Engine Efficiency ◽  
Working Cycle ◽  
Spark Timing ◽  
Ic Engines ◽  
Combustion Speed

From an ecological aspect, the hydrogen has all properties to be a very good fuel for IC engines. However the high combustion speed, as well as the possibility of backfire, is inconvenient properties of port injection. In this paper, the influence of the injection timing on the IC engine working cycle parameters (pressure and temperature) was investigated deeply. The investigation, of the injection timing influence on the IC engine working cycle parameters, was performed numerically by application of ANSYS software. It was observed the geometry of the real engine with added pre chamber, in order of layer mixture formation and pressure damping, because of high combustion speed. The results are presented for four cases with different injection timing and the same spark timing. By earlier injection, the time for mixing rise as well as the possibility of homogenization and uniform mixture creation, in pre chamber and cylinder. This claim it is confirmed on the basis of obtaining pressure and pressure rise gradient, which are growing with earlier injection, because of hydrogen combustion characteristics in stoichiometric mixture. The higher pressures as well as the surface under the diagram are positive from the aspect of the engine efficiency. However, with the earlier injection, the values of the pressure rise gradient are higher than for the classic diesel engine. This means that this phenomena can cause brutal engine work from the aspect of mechanical stresses. However the value of the maximum pressure is smaller than this in a diesel engine, this is due to added pre chamber, which has decreased the compression ratio.

Performance of Dual Fuel Engine Running on Jojoba Oil as Pilot Fuel and CNG or LPG

2007 ◽  
Author(s):  
Mohamed Y. E. Selim ◽  
M. S. Radwan ◽  
H. E. Saleh
Keyword(s):  
Methyl Ester ◽  
Natural Gas ◽  
Pressure Rise ◽  
Combustion Noise ◽  
Dual Fuel ◽  
Maximum Pressure ◽  
Injection Timing ◽  
Pressure Rise Rate ◽  
Rise Rate ◽  
Pilot Fuel

The use of Jojoba Methyl Ester as a pilot fuel was investigated for almost the first time as a way to improve the performance of dual fuel engine running on natural gas or LPG at part load. The dual fuel engine used was Ricardo E6 variable compression diesel engine and it used either compressed natural gas (CNG) or liquefied petroleum gas (LPG) as the main fuel and Jojoba Methyl Ester as a pilot fuel. Diesel fuel was used as a reference fuel for the dual fuel engine results. During the experimental tests, the following have been measured: engine efficiency in terms of specific fuel consumption, brake power output, combustion noise in terms of maximum pressure rise rate and maximum pressure, exhaust emissions in terms of carbon monoxide and hydrocarbons, knocking limits in terms of maximum torque at onset of knocking, and cyclic data of 100 engine cycle in terms of maximum pressure and its pressure rise rate. The tests examined the following engine parameters: gaseous fuel type, engine speed and load, pilot fuel injection timing, pilot fuel mass and compression ratio. Results showed that using the Jojoba fuel with its improved properties has improved the dual fuel engine performance, reduced the combustion noise, extended knocking limits and reduced the cyclic variability of the combustion.

Experimental investigations on combustion of jatropha methyl ester in a turbocharged direct-injection diesel engine

2008 ◽  
Vol 222 (10) ◽  
pp. 1865-1877 ◽  
Author(s):  
K Anand ◽  
R P Sharma ◽  
P S Mehta
Keyword(s):  
Diesel Engine ◽  
Methyl Ester ◽  
Diesel Fuel ◽  
Fuel Injection ◽  
Peak Pressure ◽  
Direct Injection ◽  
Pressure Rise ◽  
Experimental Investigations ◽  
Injection Timing ◽  
Gas Temperature

Suitability of vegetable oil as an alternative to diesel fuel in compression ignition engines has become attractive, and research in this area has gained momentum because of concerns on energy security, high oil prices, and increased emphasis on clean environment. The experimental work reported here has been carried out on a turbocharged direct-injection multicylinder truck diesel engine using diesel fuel and jatropha methyl ester (JME)-diesel blends. The results of the experimental investigation indicate that an increase in JME quantity in the blend slightly advances the dynamic fuel injection timing and lowers the ignition delay compared with the diesel fuel. A maximum rise in peak pressure limited to 6.5 per cent is observed for fuel blends up to 40 per cent JME for part-load (up to about 50 per cent load) operations. However, for a higher-JME blend, the peak pressures decrease at higher loads remained within 4.5 per cent. With increasing proportion of JME in the blend, the peak pressure occurrence slightly advances and the maximum rate of pressure rise, combustion duration, and exhaust gas temperature decrease by 9 per cent, 15 per cent and 17 per cent respectively. Although the changes in brake thermal efficiencies for 20 per cent and 40 per cent JME blends compared with diesel fuel remain insignificant, the 60 per cent JME blend showed about 2.7 per cent improvement in the brake thermal efficiency. In general, it is observed that the overall performance and combustion characteristics of the engine do not alter significantly for 20 per cent and 40 per cent JME blends but show an improvement over diesel performance when fuelled with 60 per cent JME blend.

scholarly journals Assessing the optimum combustion under constrained conditions

2018 ◽  
Vol 21 (5) ◽  
pp. 811-823 ◽  
Author(s):  
Pablo Olmeda ◽  
Jaime Martín ◽  
Ricardo Novella ◽  
Diego Blanco-Cavero
Keyword(s):  
Heat Transfer ◽  
Diesel Engine ◽  
Heat Release ◽  
Engine Speed ◽  
Direct Injection ◽  
Pressure Rise ◽  
Maximum Pressure ◽  
Low Load ◽  
Negative Effect ◽  
Constrained Conditions

This work studies the optimum heat release law of a direct injection diesel engine under constrained conditions. For this purpose, a zero-dimensional predictive model of a diesel engine is coupled to an optimization tool used to shape the heat release law in order to optimize some outputs (maximize gross indicated efficiency and minimize NO x emissions) while keeping several restrictions (mechanical limits such as maximum peak pressure and maximum pressure rise rate). In a first step, this methodology is applied under different heat transfer scenarios without restrictions to evaluate the possible gain obtained through the thermal isolation of the combustion chamber. Results derived from this study show that heat transfer has a negative effect on gross indicated efficiency ranging from −4% of the fuel energy ( ṁfHv), at high engine speed and load, up to −8% ṁfHv, at low engine speed and load. In a second step, different mechanical limits are applied resulting in a gross indicated efficiency worsening from −1.4% ṁfHv up to −2.8% ṁfHv compared to the previous step when nominal constraints are applied. In these conditions, a temperature swing coating that covers the piston top and cylinder head is considered obtaining a maximum gross indicated efficiency improvement of +0.5% ṁfHv at low load and engine speed. Finally, NO x emissions are also included in the optimization obtaining the expected tradeoff between gross indicated efficiency and NO x. Under this optimization, cutting down the experimental emissions by 50% supposes a gross indicated efficiency penalty up to −8% ṁfHv when compared to the optimum combustion under nominal limits, while maintaining the experimental gross indicated efficiency allows to reduce the experimental emissions 30% at high load and 65% at low load and engine speed.

Combustion of Raw Algae Oil and Its Methyl Ester in a Diesel Engine

2010 ◽  
Author(s):  
Yousef Haik ◽  
Mohamed Y. E. Selim ◽  
Taher Abdulrehman
Keyword(s):  
Diesel Engine ◽  
Methyl Ester ◽  
Compression Ratio ◽  
Combustion Noise ◽  
Design Parameters ◽  
Maximum Pressure ◽  
Injection Timing ◽  
Maximum Heat ◽  
Output Torque ◽  
Algae Oil

An experimental study has been carried to use raw Algae oil and its methyl esters in an indirect injection diesel engine. Effects of engine speed, engine load output, injection timing of the algae biofuel and engine compression ratio on the engine output torque, combustion noise (maximum pressure rise rate), maximum pressure and maximum heat release rate have been studied. Raw oil extracted from microalgae and its methyl ester have been evaluated in a Ricardo E6 engine. It has been shown that the algae oil methyl ester’s properties are similar to diesel fuel and its use has been successful in running the diesel engine smoothly. However, its use reduced the engine output torque slightly and increased the combustion noise. Nonetheless, the engine output can be increased and the combustion noise can be reduced by controlling the engine design parameters e.g. injection timing and compression ratio.

Low NOx and Low Smoke Operation of a Diesel Engine Using Gasolinelike Fuels

2010 ◽  
Vol 132 (9) ◽  
Author(s):  
Gautam Kalghatgi ◽  
Leif Hildingsson ◽  
Bengt Johansson
Keyword(s):  
Diesel Engine ◽  
Heat Release ◽  
Compression Ratio ◽  
Diesel Fuel ◽  
Ignition Delay ◽  
Cetane Number ◽  
Pressure Rise ◽  
Maximum Pressure ◽  
Single Cylinder ◽  
Intake Pressure

Much of the technology in advanced diesel engines, such as high injection pressures, is aimed at overcoming the short ignition delay of conventional diesel fuels to promote premixed combustion in order to reduce NOx and smoke. Previous work in a 2 l single-cylinder diesel engine with a compression ratio of 14 has demonstrated that gasoline fuel, because of its high ignition delay, is very beneficial for premixed compression-ignition compared with a conventional diesel fuel. We have now done similar studies in a smaller—0.537 l—single-cylinder diesel engine with a compression ratio of 15.8. The engine was run on three fuels of very different auto-ignition quality—a typical European diesel fuel with a cetane number (CN) of 56, a typical European gasoline of 95 RON and 85 MON with an estimated CN of 16 and another gasoline of 84 RON and 78 MON (estimated CN of 21). The previous results with gasoline were obtained only at 1200 rpm—here we compare the fuels also at 2000 rpm and 3000 rpm. At 1200 rpm, at low loads (∼4 bars indicated mean effective pressure (IMEP)) when smoke is negligible, NOx levels below 0.4 g/kWh can be easily attained with gasoline without using exhaust gas recirculation (EGR), while this is not possible with the 56 CN European diesel. At these loads, the maximum pressure-rise rate is also significantly lower for gasoline. At 2000 rpm, with 2 bars absolute intake pressure, NOx can be reduced below 0.4 g/kW h with negligible smoke (FSN<0.1) with gasoline between 10 bars and 12 bars IMEP using sufficient EGR, while this is not possible with the diesel fuel. At 3000 rpm, with the intake pressure at 2.4 bars absolute, NOx of 0.4 g/kW h with negligible smoke was attainable with gasoline at 13 bars IMEP. Hydrocarbon and CO emissions are higher for gasoline and will require after-treatment. High peak heat release rates can be alleviated using multiple injections. Large amounts of gasoline, unlike diesel, can be injected very early in the cycle without causing heat release during the compression stroke and this enables the heat release profile to be shaped.

Influence of Micro-Emulsified Biodiesel on Combustion and Emission Characteristics of a Turbocharged Diesel Engine

2012 ◽  
Vol 608-609 ◽  
pp. 269-274
Author(s):  
Qi Min Wu ◽  
Ping Sun ◽  
De Qing Mei ◽  
Zhen Chen
Keyword(s):  
Diesel Engine ◽  
Combustion Process ◽  
Pressure Rise ◽  
Operating Conditions ◽  
Maximum Pressure ◽  
Emission Characteristics ◽  
Combustion Duration ◽  
Rise Rate ◽  
Di Diesel Engine ◽  
Emulsified Biodiesel

In this paper, two kinds of micro-emulsified biodiesel containing 5.6% and10% water are prepared. The effects of micro-emulsified biodiesel on engine’s power, combustion and emission characteristics are investigated in a DI diesel engine. The results show that under the rated speed and full load operating conditions, the maximum pressure rise rate and peak heat release rate for micro-emulsified biodiesel increase dramatically, while the ignition delay is prolonged and the combustion duration becomes shorter. Compared to base diesel, the HC, CO and smoke emissions from the engine fueled with biodiesel decrease sharply, except for a 9% increased NOx at large loads. However, micro-biodiesel could significantly reduce the NOx and smoke emissions, except for the higher HC and CO emissions at low and medium loads. When fuelled with 10%MB, the NOx and smoke emissions are 9% and 90% lower than that of diesel, respectively. Results reported here suggest that the application of micro-emulsified biodiesel in diesel engines has a potential to improve combustion process and reduce NOx, PM emissions simultaneously.

scholarly journals Effects of ethanol port injection timing and delivery rate on combustion characteristic of a heavy-duty V12 diesel engine

2021 ◽  
pp. 137-137
Author(s):  
Kien Nguyen Trung ◽  
Hai Hoang Tuan
Keyword(s):  
Diesel Engine ◽  
Fossil Fuels ◽  
Pressure Rise ◽  
Delivery Rate ◽  
Combustion Characteristic ◽  
Injection Timing ◽  
Heavy Duty ◽  
Characteristic Analysis ◽  
Ethanol Injection ◽  
Reduce Emissions

Using bio-based fuels in diesel engines is an effective solution to reduce the generation of toxic components in the exhaust gas. One of them, alcohol, is the potential fuel to reduce emissions and dependence on fossil fuels. So, this study is aimed to investigate the effects of ethanol port injection timing and delivery rate on the combustion characteristic of a heavy-duty V-12 diesel engine when ethanol substitution percentage is 30% to reach the original diesel quantity at full load. The combustion characteristic analysis indicates that the variation in cylinder gas pressure and temperature decreases when retarded ethanol injection timing and decreased ethanol delivery rate, the engine works more smoothly due to the maximum rate of pressure rise decreases. However, the changes are greater when changing the ethanol injection timing as compared to ethanol delivery rate case.

Low NOx and Low Smoke Operation of a Diesel Engine Using Gasoline-Like Fuels

2009 ◽  
Author(s):  
Gautam Kalghatgi ◽  
Leif Hildingsson ◽  
Bengt Johansson
Keyword(s):  
Diesel Engine ◽  
Heat Release ◽  
Compression Ratio ◽  
Diesel Fuel ◽  
Ignition Delay ◽  
Cetane Number ◽  
Pressure Rise ◽  
Maximum Pressure ◽  
Single Cylinder ◽  
Intake Pressure

Much of the technology in advanced diesel engines, such as high injection pressures, is aimed at overcoming the short ignition delay of conventional diesel fuels to promote premixed combustion in order to reduce NOx and smoke. Previous work in a 2 litre single cylinder diesel engine with a compression ratio of 14 has demonstrated that gasoline fuel, because of its high ignition delay, is very beneficial for premixed compression ignition compared to a conventional diesel fuel. We have now done similar studies in a smaller — 0.537 litre — single cylinder diesel engine with a compression ratio of 15.8. The engine was run on three fuels of very different auto-ignition quality — a typical European diesel fuel with a cetane number (CN) of 56, a typical European gasoline of 95 RON and 85 MON with an estimated CN of 16 and another gasoline of 84 RON and 78 MON (estimated CN of 21). The previous results with gasoline were obtained only at 1200 rpm — here we compare the fuels also at 2000 rpm and 3000 rpm. At 1200 rpm, at low loads (∼4 bar IMEP) when smoke is negligible, NOx levels below 0.4 g/kWh can be easily attained with gasoline without using EGR while this is not possible with the 56 CN European diesel. At these loads, the maximum pressure rise rate is also significantly lower for gasoline. At 2000 rpm, with 2 bar absolute intake pressure, NOx can be reduced below 0.4 g/kWh with negligible smoke (FSN <0.1) with gasoline between 10 and 12 bar IMEP using sufficient EGR while this is not possible with the diesel fuel. At 3000 rpm, with the intake pressure at 2.4 bar absolute, NOx of 0.4 g/KWh with negligible smoke was attainable with gasoline at 13 bar IMEP. Hydrocarbon and CO emissions are higher for gasoline and will require after-treatment. High peak heat release rates can be alleviated using multiple injections. Large amounts of gasoline, unlike diesel, can be injected very early in the cycle without causing heat release during the compression stroke and this enables the heat release profile to be shaped.

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