Studies on Influence of Injection Timing and Diesel Replacement on LPG-Diesel Dual-Fuel Engine

2003 ◽  
Author(s):  
C. V. Sudhir ◽  
Vijay Desai ◽  
Y. Suresh Kumar ◽  
P. Mohanan
Keyword(s):  
Energy Consumption ◽  
Diesel Engine ◽  
Fuel Consumption ◽  
Thermal Efficiency ◽  
Dual Fuel ◽  
Injection Timing ◽  
Brake Thermal Efficiency ◽  
Full Load ◽  
Smoke Density ◽  
Diesel Operation

Reducing the emissions and fuel consumption for IC engines are no longer the future goals; instead they are the demands of today. People are concerned about rising fuel costs and effects of emissions on the environment. The major contributor for the increased levels of pollutants is the Diesel engines. Diesel engine finds application in almost in all fields, including transportation sector such as buses, trucks, railway engines, etc. and in industries as power generating units. In the present work an attempt is made for effective utilization of diesel engine aiming for reduction in fuel consumption and smoke density. This is achieved by some minor modifications in diesel engine, so as to run the existing diesel engine as a LPG-Diesel dual-fuel engine with LPG (Liquefied Petroleum Gas) induction at air intake. The important aspect of LPG-Diesel dual-fuel engine is that it shows significant reduction in smoke density and improved brake thermal efficiency with reduced energy consumption. An existing 4-S, single cylinder, naturally aspirated, water-cooled, direct injection, CI engine test rig was used for the experimental purpose. With proper instrumentation the tests were conducted under various LPG flow rates, loads, and injection timings. The influence of the diesel replacement by LPG on smoke density, brake specific energy consumption and brake thermal efficiency were studied. The optimal diesel replacement pertaining to the maximum allowable LPG gas flow limits could be assessed with these experiments. The influence of the injection timing variation on the engine performance and smoke density were analyzed form the experimental results. It was also observed that beyond half load operation of the dual-fuel engine, the brake thermal efficiency increases with diesel replacement, and at full load up to 4% improvement was observed compared to full diesel operation. At full load reduction in smoke density up to 25–36% was observed compared to full diesel operation. At advance injection timing of 30°btdc the performance was better with lower emissions compared to normal and retarded injection timings.

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

2013 ◽  
Vol 11 ◽  
pp. 27-44 ◽  
Author(s):  
N. Janardhan ◽  
M.V.S. Murali Krishna ◽  
P. Ushasri ◽  
P.V.K. Murthy
Keyword(s):  
Diesel Engine ◽  
Thermal Efficiency ◽  
Peak Pressure ◽  
Air Gap ◽  
Injection Timing ◽  
Jatropha Oil ◽  
Opening Pressure ◽  
Brake Thermal Efficiency ◽  
Heat Rejection ◽  
Diesel Operation

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.

Factors Affecting Performance of Dual Fuel Compression Ignition Engines

2013 ◽  
Vol 388 ◽  
pp. 217-222
Author(s):  
Mohamed Mustafa Ali ◽  
Sabir Mohamed Salih
Keyword(s):  
Diesel Engine ◽  
Fuel Consumption ◽  
Thermal Efficiency ◽  
Fuel Injection ◽  
Direct Injection ◽  
Injection System ◽  
Dual Fuel ◽  
Injection Timing ◽  
Compression Ignition ◽  
Factors Affecting

Compression Ignition Diesel Engine use Diesel as conventional fuel. This has proven to be the most economical source of prime mover in medium and heavy duty loads for both stationary and mobile applications. Performance enhancements have been implemented to optimize fuel consumption and increase thermal efficiency as well as lowering exhaust emissions on these engines. Recently dual fueling of Diesel engines has been found one of the means to achieve these goals. Different types of fuels are tried to displace some of the diesel fuel consumption. This study is made to identify the most favorable conditions for dual fuel mode of operation using Diesel as main fuel and Gasoline as a combustion improver. A single cylinder naturally aspirated air cooled 0.4 liter direct injection diesel engine is used. Diesel is injected by the normal fuel injection system, while Gasoline is carbureted with air using a simple single jet carburetor mounted at the air intake. The engine has been operated at constant speed of 3000 rpm and the load was varied. Different Gasoline to air mixture strengths investigated, and diesel injection timing is also varied. The optimum setting of the engine has been defined which increased the thermal efficiency, reduced the NOx % and HC%.

Dual-Fueling of a Prechamber Diesel Engine With Natural Gas

1985 ◽  
Vol 107 (4) ◽  
pp. 914-921 ◽  
Author(s):  
S. Song ◽  
P. G. Hill
Keyword(s):  
Energy Consumption ◽  
Diesel Engine ◽  
Natural Gas ◽  
Consumption Rate ◽  
Dual Fuel ◽  
Combustion Mechanism ◽  
Injection Timing ◽  
Cylinder Pressure ◽  
Energy Consumption Rate ◽  
Diesel Operation

The feasibility of dual-fuel operation with natural gas in a prechamber diesel engine was studied with special emphasis on fuel consumption and cylinder pressure development. The effects of air restriction, pilot diesel flow rate, and injection timing were also investigated. Near full load the fuel energy consumption rate was close to that of straight diesel operation though at part load (in the absence of air restriction) the fuel energy consumption rate was relatively high. In the absence of injection timing adjustment the maximum power output of dual-fuel operation was severely limited by the maximum cylinder pressure. Retarding the injection timing is effective in reducing the maximum cylinder pressure to a safe level. The analysis of apparent energy release indicates the differences in combustion mechanism between auto-ignition of diesel fuel in straight diesel operation and propagation of flame fronts in dual-fuel operation.

Experimental Investigations on a Compressed Natural Gas Operated Dual Fuel Engine

2005 ◽  
Author(s):  
N. Kapilan ◽  
Chandramohan Somayaji ◽  
P. Mohanan ◽  
R. P. Reddy
Keyword(s):  
Diesel Engine ◽  
Natural Gas ◽  
Thermal Efficiency ◽  
Experimental Investigations ◽  
Dual Fuel ◽  
Nox Emissions ◽  
Compressed Natural Gas ◽  
Brake Thermal Efficiency ◽  
Full Load ◽  
Performance And Emissions

In the present work, an attempt has been made for the effective utilization of Compressed Natural Gas (CNG) in diesel engine. A four stroke, single cylinder diesel engine was modified to work on dual fuel mode. The effect of CNG flow rate and Exhaust Gas Recirclulation (EGR) on the performance and emissions of the dual fuel engine was studied. The variables considered for the tests were different CNG flow rates (0.2, 0.3, 0.4, 0.5, 0.6 and 0.7 kg/hr), EGR (0 %, 4.28 %, 6.63 % and 8.12 %) and loads (25 %, 50 %, 75 % and 100 % of full load). From the test results, it was observed that the EGR rate of 4.28 % results in better brake thermal efficiency and lower CO and NOx emissions than other ERG rates at 25 %, 50% and 75% of full loads. At full load, EGR rate of 8.12 % results in higher brake thermal efficiency and lower NOx emissions.

scholarly journals EFFECT OF COMPRESSION RATIO ON PERFORMANCE OF A HYDROGEN BLENDED CNG-DIESEL DUAL FUEL ENGINE

2015 ◽  
Vol 44 (2) ◽  
pp. 87-93 ◽  
Author(s):  
Sridhara Reddy ◽  
Maheswar Dutta ◽  
K.Vijaya Kumar Reddy
Keyword(s):  
Energy Consumption ◽  
Specific Energy ◽  
Compression Ratio ◽  
Thermal Efficiency ◽  
Specific Energy Consumption ◽  
Dual Fuel ◽  
Operating Parameters ◽  
Brake Thermal Efficiency ◽  
Performance And Emission ◽  
Emission Behavior

Compression ratios of the engine considerably affect the performance and emission behavior of an engine.The paper discusses about effect of compression ratios on the operating parameters such as brake specific fuelconsumption (BSFC), brake specific energy consumption (BSEC), brake thermal efficiency (BTE) and volumetricefficiency on a stationary diesel-CNG dual fuel engine by adding hydrogen fraction as a combustion booster. Theexhaust emission behavior of the engine is also presented. Addition of hydrogen in CNG has given better resultsthan diesel-CNG dual fuel operation of the engine. The volumetric efficiency and emissions like NOx are theparameters which needed attention towards this study. The paper presents experimental results and analyzes them.

Effect of Water Injection in Acetylene-Diesel Dual Fuel DI Diesel Engine

2012 ◽  
Author(s):  
T. Lakshmanan ◽  
A. Khadeer Ahmed ◽  
G. Nagarajan
Keyword(s):  
Diesel Engine ◽  
Thermal Efficiency ◽  
Alternative Fuels ◽  
Gas Flow ◽  
Water Injection ◽  
Intake Manifold ◽  
Dual Fuel ◽  
Intake Port ◽  
Gas Temperature ◽  
Brake Thermal Efficiency

Gaseous fuels are good alternative fuels to improve the energy crisis of today’s situation due to its clean burning characteristics. However, the incidence of backfire and knock remains a significant barrier in commercialization. With the invention of latest technology, the above barriers are eliminated. One such technique is timed injection of water into the intake port. In the present investigation, acetylene was aspirated in the intake manifold of a single cylinder diesel engine, with a gas flow rate of 390 g/h, along with water injected in the intake port, to overcome the backfire and knock problems in gaseous dual fuel engine. The brake thermal efficiency and emissions such as NOx, smoke, CO, HC, CO2 and exhaust gas temperature were studied. Dual fuel operation of acetylene induction with injection of water results in lowered NOx emissions with complete elimination of backfire and knock at the expense of brake thermal efficiency.

Cyclic Variability in Diesel/Gasoline Dual-Fuel Combustion on a Medium-Duty Diesel Engine

2013 ◽  
Author(s):  
Jiafeng Sun ◽  
Joshua A. Bittle ◽  
Timothy J. Jacobs
Keyword(s):  
Diesel Engine ◽  
Heat Release ◽  
Gasoline Fraction ◽  
Fuel Spray ◽  
Intake Manifold ◽  
Dual Fuel ◽  
Injection Timing ◽  
Fuel Injector ◽  
Cyclic Variability ◽  
Diesel Operation

Most studies comparing diesel/gasoline dual-fuel operation and single-fuel diesel operation in diesel engines center on time-averaged results. It seems few studies discuss differences in cyclic variability. Motivated by this, the present study evaluates the cyclic variability of combustion in both dual-fuel and single-fuel operations of a diesel engine. Steady-state tests were done on a medium duty diesel engine with conventional direct injection timings of diesel fuel into the cylinder at one speed and three loads. In addition to single-fuel (diesel) operation, dual-fuel (gasoline and diesel) operation was studied at increasing levels of gasoline fraction. Gasoline fuel is introduced via a fuel injector at a single location prior to the intake manifold (and EGR mixing location). Crank-angle resolved data including in-cylinder pressure and heat release rate obtained for around 150 consecutive cycles are used to assess cyclic variability. The sources of cyclic variability, namely the factors causing cyclic variability or influencing its magnitude, especially those related to cylinder charge amount and mixture preparation, are analyzed. Fuel spray penetration and cyclic variability of cylinder charging, overall A/F ratio, and fuel injection timing, tend to increase cyclic variability of combustion in dual-fuel operation. On the other hand, fuel type and fuel spray droplet size tend to increase cyclic variability in single-fuel operation. The cyclic variability in dual-fuel operation in this study is more serious than that in single-fuel operation, in terms of magnitude, indicated by metrics chosen to quantify it. Most measures of cyclic variability increase consistently with increasing gasoline fraction. Variations of gasoline amount and possibly gasoline low temperature heat release cause higher combustion variation in dual-fuel operation primarily by affecting premixed burning. Statistical methods such as probability density function, autocorrelation coefficient, return map, and symbol sequence statistics methods are used to check determinism. In general, the parameters studied do not show strong determinism, which suggests other parameters must be identified to establish determinism or the system is inherently stochastic. Regardless, dominant sequences and optimal sequence lengths can be identified.

Potential of a Medium Grade Low Heat Rejection Diesel Engine With Crude Tobacco Seed Oil

2013 ◽  
Author(s):  
M. V. S. Murali Krishna ◽  
P. Pavan Kumar ◽  
P. V. K. Murthy ◽  
D. Baswaraju
Keyword(s):  
Diesel Engine ◽  
Maximum Rate ◽  
Seed Oil ◽  
Peak Pressure ◽  
Injection Pressure ◽  
Air Gap ◽  
Injection Timing ◽  
Brake Thermal Efficiency ◽  
Tobacco Seed ◽  
Diesel Operation

Investigations were carried out to evaluate the performance of a medium grade low heat rejection (LHR) diesel engine consisting of air gap insulated piston with 3-mm air gap, with superni (an alloy of nickel) crown and air gap insulated liner with superni insert with different operating conditions of crude tobacco seed oil with varied injection timing and injection pressure. Performance parameters of brake thermal efficiency (BTE), exhaust gas temperature (EGT), volumetric efficiency (VE), coolant load (CL) and sound intensity were determined at various values of brake mean effective pressure (BMEP) of the engine. Exhaust emissions of smoke and oxides of nitrogen (NOx) were noted at different values of BMEP of the engine. Combustion characteristics of peak pressure (PP), time of occurrence of peak pressure (TOPP), maximum rate of pressure rise (MRPR) and time of occurrence of maximum rate of pressure (TOMRPR) were measured with TDC (top dead centre) encoder, pressure transducer, console and special pressure-crank angle software-package at the peak load operation of the engine. Conventional engine (CE) showed deteriorated performance, while LHR engine showed improved performance with crude tobacco seed oil (CTSO) operation when compared with pure diesel operation at recommended injection timing and pressure. The optimum injection timing was found to be 32°bTDC (before top dead centre) with CE while it was 30°bTDC with LHR engine with vegetable oil operation. The performance of both version of the engine improved with advanced injection timing and higher injection pressure with test fuels. Peak brake thermal efficiency increased by 4%, volumetric efficiency decreased by 8%, smoke levels decreased by 4% and NOx levels increased by 37% with vegetable oil operation on LHR engine at its optimum injection timing, when compared with pure diesel operation on CE at manufacturer’s recommended injection timing of 27°bTDC.

The Comparative Trail Research on the Performance of a Diesel Engine Fuelled with Diesel Fuel and Biodiesel/Diesel Blended Fuel

2011 ◽  
Vol 142 ◽  
pp. 103-106
Author(s):  
Wen Ming Cheng ◽  
Hui Xie ◽  
Gang Li
Keyword(s):  
Diesel Engine ◽  
Fuel Consumption ◽  
Diesel Fuel ◽  
Thermal Efficiency ◽  
Specific Fuel Consumption ◽  
Brake Specific Fuel Consumption ◽  
Brake Thermal Efficiency ◽  
Series Of Experiments ◽  
Blended Fuel ◽  
Load Conditions

This paper discusses the brake specific fuel consumption and brake thermal efficiency of a diesel engine using cottonseed biodiesel blended with diesel fuel. A series of experiments were conducted for the various blends under varying load conditions at a speed of 1500 rpm and 2500 rpm and the results were compared with the neat diesel. From the results, it is found that the brake specific fuel consumption of cottonseed biodiesel is slightly higher than that of diesel fuel at different engine loads and speeds, with this increase being higher the higher the percentage of the biodiesel in the blend. And the brake thermal efficiency of cottonseed biodiesel is nearly similar to that of diesel fuel at different engine loads and speeds. From the investigation, it is concluded that cottonseed biodiesl can be directly used in diesel engines without any modifications, at least in small blending ratios.

scholarly journals Performance and emissions of a single cylinder diesel engine operating with rapeseed oil and jp-8 fuel blends

2015 ◽  
Vol 162 (3) ◽  
pp. 13-18
Author(s):  
Gvidonas Labeckas ◽  
Irena Kanapkienė
Keyword(s):  
Diesel Engine ◽  
Fuel Consumption ◽  
Thermal Efficiency ◽  
Rapeseed Oil ◽  
Jet Fuel ◽  
Brake Specific Fuel Consumption ◽  
Test Results ◽  
Brake Thermal Efficiency ◽  
Engine Load ◽  
Fuel Blends

The article presents experimental test results of a DI single-cylinder, air-cooled diesel engine FL 511 operating with the normal (class 2) diesel fuel (DF), rapeseed oil (RO) and its 10%, 20% and 30% (v/v) blends with aviation-turbine fuel JP-8 (NATO code F-34). The purpose of the research was to analyse the effects of using various rapeseed oil and jet fuel RO90, RO80 and RO70 blends on brake specific fuel consumption, brake thermal efficiency, emissions and smoke of the exhaust. The test results of engine operation with various rapeseed oil and jet fuel blends compared with the respective parameters obtained when operating with neat rapeseed oil and those a straight diesel develops at full (100%) engine load and maximum brake torque speed of 2000 rpm. The research results showed that jet fuel added to rapeseed oil allows to decrease the value of kinematic viscosity making such blends suitable for the diesel engines. Using of rapeseed oil and jet fuel blends proved themselves as an effective measure to maintain fuel-efficient performance of a DI diesel engine. The brake specific fuel consumption decreased by about 6.1% (313.4 g/kW·h) and brake thermal efficiency increase by nearly 1.0% (0.296) compared with the respective values a fully (100%) loaded engine fuelled with pure RO at the same test conditions. The maximum NOx emission was up to 13.7% higher, but the CO emissions and smoke opacity of the exhaust 50.0% and 3.4% lower, respectively, for the engine powered with biofuel blend RO70 compared with those values produced by the combustion of neat rapeseed oil at full (100%) engine load and speed of 2000 rpm.

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