Investigations on Low Heat Rejection Diesel Engine With Crude Jatropha Oil as an Alternate Fuel

2002 ◽  
Author(s):  
M. V. S. Murali Krishna ◽  
C. M. Vara Prasad ◽  
Tandur Rajashekar ◽  
Supriya Tiwari ◽  
T. Sujani
Keyword(s):  
Diesel Engine ◽  
Diesel Fuel ◽  
Injection Pressure ◽  
High Viscosity ◽  
Injection Timing ◽  
Jatropha Oil ◽  
Heat Rejection ◽  
Reduction Of Nox ◽  
Conventional Diesel Fuel ◽  
Diesel Operation

Jatropha oil, a non-edible vegetable oil shows a greater potential for replacing conventional diesel fuel quite effectively, as its properties are compatible to that of diesel fuel. But low volatility and high viscosity of jatropha oil call for hot combustion chamber, which is provided by a low heat rejection diesel engine with threaded air gap piston and liner with superni-90 inserts. The performance of the engine with jatropha oil is obtained with different versions of the engine such as conventional engine and insulated engine at normal and preheat condition of the oil, with varying injection pressure and timing and compared to the engine with pure diesel operation at recommended injection pressure and timing. Increase of thermal efficiency of 18% and reduction of NOx levels by 5% are observed at optimized injection timing and at higher injection pressure with insulated engine at preheat condition of jatropha oil in comparison with pure diesel operation on conventional engine.

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.

scholarly journals Performance Evaluation of a Low-Grade Low-Heat-Rejection Diesel Engine with Crude Pongamia oil

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Ch. Kesava Reddy ◽  
M. V. S. Murali Krishna ◽  
P. V. K. Murthy ◽  
T. Ratna Reddy
Keyword(s):  
Diesel Engine ◽  
Cylinder Head ◽  
Peak Load ◽  
Injection Pressure ◽  
Operating Conditions ◽  
Injection Timing ◽  
Low Grade ◽  
Heat Rejection ◽  
Pongamia Oil ◽  
Diesel Operation

Investigations are carried out to evaluate the performance of a low heat rejection (LHR) diesel engine with ceramic coated cylinder head [ceramic coating of thickness 500 microns is done on inside portion of cylinder head] with different operating conditions [normal temperature and pre-heated temperature] of crude Pongamia oil (CPO) with varied injection pressure and injection timing. Performance parameters and pollution levels are determined at various magnitudes of brake mean effective pressure. Combustion characteristics at peak load operation of the engine are measured with special pressure-crank angle software package. Conventional engine (CE) showed deteriorated performance, while LHR engine showed improved performance with CPO operation at recommended injection timing and pressure and the performance of both version of the engine is improved with advanced injection timing and at higher injection pressure when compared with CE with pure diesel operation. The optimum injection timing is 31°bTDC for conventional engine while it is 29°bTDC with LHR engine with vegetable oil operation. Peak brake thermal efficiency increased by 5%, smoke levels decreased by 2% and NOx levels increased by 40% with CPO operation on LHR engine at its optimum injection timing, when compared with pure diesel operation on CE at manufacturer’s recommended injection timing.

Spray and Combustion Characteristics of Biodiesel∕Diesel Blended Fuel in a Direct Injection Common-Rail Diesel Engine

2008 ◽  
Vol 130 (3) ◽  
Author(s):  
Hyun Kyu Suh ◽  
Hyun Gu Roh ◽  
Chang Sik Lee
Keyword(s):  
Diesel Engine ◽  
Diesel Fuel ◽  
Direct Injection ◽  
Injection Rate ◽  
Combustion Characteristics ◽  
Biodiesel Fuel ◽  
Injection Timing ◽  
Pilot Injection ◽  
Blended Fuel ◽  
Conventional Diesel Fuel

The aim of this work is to investigate the effect of the blending ratio and pilot injection on the spray and combustion characteristics of biodiesel fuel and compare these factors with those of diesel fuel in a direct injection common-rail diesel engine. In order to study the factors influencing the spray and combustion characteristics of biodiesel fuel, experiments involving exhaust emissions and engine performance were conducted at various biodiesel blending ratios and injection conditions for engine operating conditions. The macroscopic and microscopic spray characteristics of biodiesel fuel, such as injection rate, split injection effect, spray tip penetration, droplet diameter, and axial velocity distribution, were compared with the results from conventional diesel fuel. For biodiesel blended fuel, it was revealed that a higher injection pressure is needed to achieve the same injection rate at a higher blending ratio. The spray tip penetration of biodiesel fuel was similar to that of diesel. The atomization characteristics of biodiesel show that it has higher Sauter mean diameter and lower spray velocity than conventional diesel fuel due to high viscosity and surface tension. The peak combustion pressures of diesel and blending fuel increased with advanced injection timing and the combustion pressure of biodiesel fuel is higher than that of diesel fuel. As the pilot injection timing is retarded to 15deg of BTDC that is closed by the top dead center, the dissimilarities of diesel and blending fuels combustion pressure are reduced. It was found that the pilot injection enhanced the deteriorated spray and combustion characteristics of biodiesel fuel caused by different physical properties of the fuel.

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.

Experimental Investigations on DI Diesel Engine With Low Heat Rejection Combustion Chamber With Carbureted Ethanol and Crude Jatropha Oil

2015 ◽  
Author(s):  
Vencherla V. R. Seshagiri Rao ◽  
Maddali V. S. Murali Krishna ◽  
T. Kishen Kumar Reddy ◽  
D. Srikanth ◽  
P. V. Krishna Murthy
Keyword(s):  
Diesel Engine ◽  
Combustion Chamber ◽  
Vegetable Oil ◽  
Air Gap ◽  
Injection Timing ◽  
Jatropha Oil ◽  
Heat Rejection ◽  
Full Load ◽  
Full Load Operation ◽  
Ci Engines

It has been found that the vegetable oils and alcohols (ethanol and methanol) are promising substitute fuels for diesel fuel, because they are renewable in nature. However drawbacks associated with crude vegetable oil (high viscosity and low volatility) and ethanol (low cetane number and low energy content) which cause combustion problems in CI engines, call for engine with hot combustion chamber. Investigations were carried out on single–cylinder, four–stroke, water cooled, 3.68 kW direct injection diesel engine at a speed of 1500 rpm to evaluate the performance of a engine with medium grade low heat rejection (LHR) combustion chamber. It consisted of an air gap insulated piston and an air gap insulated liner fuelled with crude jatropha oil and carbureted ethanol with varied injection timing and injector opening pressure. Carbureted ethanol was inducted into the engine through a variable jet carburetor. This carburetor was installed at the inlet manifold of the engine and ethanol was inducted at different percentages of crude vegetable oil at full load operation on mass basis. Aldehydes (measured by dinitrophenyl hydrazine method), particulate emissions and oxides of nitrogen were measured at full load operation of the engine. With maximum induction of ethanol, engine with LHR combustion chamber showed improved performance over conventional engine at 27°bTDC and optimized injection timing.

scholarly journals Performance of Semi Adiabatic DI Diesel Engine with Supercharged air using Crude Jatropha Oil

2020 ◽  
Vol 9 (5) ◽  
pp. 10-16
Keyword(s):  
Developing Countries ◽  
Diesel Engine ◽  
Injection Pressure ◽  
Edible Oil ◽  
Intake Manifold ◽  
Injection Timing ◽  
High Grade ◽  
Jatropha Oil ◽  
Waste Land ◽  
Di Diesel Engine

Vegetable oils are the only fuels, can be substituted as alternative to overcome the shortage in developing countries. Using non-edible oil like crude jatropha as alternative, waste land can be effectively cultivated and employment can be improved. Experiments were Initiated on semi adiabatic diesel engine with super charging air through the intake manifold using crude jatropha oil with varied injection pressure and varied injection timing to study the performance of the engine. Tests were also conducted using diesel fuel in diesel engine and engine with high grade heat rejection combustion chamber at recommended injection timing at 270 bTDC with super charging air using crude jatropha oil. Improvement in performance was found with super charging when comparing with natural aspiration.

Spray and Combustion Characteristics of Biodiesel Fuel in a Direct Injection Common-Rail Diesel Engine

2007 ◽  
Author(s):  
Hyun Kyu Suh ◽  
Hyun Gu Rho ◽  
Chang Sik Lee
Keyword(s):  
Diesel Engine ◽  
Diesel Fuel ◽  
Direct Injection ◽  
Injection Rate ◽  
Combustion Characteristics ◽  
Common Rail ◽  
Biodiesel Fuel ◽  
Injection Timing ◽  
Pilot Injection ◽  
Conventional Diesel Fuel

The aim of this work is to investigate the effect of mixing ratio and pilot injection on spray and combustion characteristics of biodiesel fuel and compared with those of diesel fuel in a direct injection common-rail diesel engine. In order to study the influence factors of biodiesel fuel on the spray and combustion characteristics, the experiments were conducted at various mixing ratios and injection conditions of the biodiesel and engine operating conditions. The macroscopic and microscopic characteristics such as injection rate, split injection effect, spray tip penetration, droplet diameter, and axial velocity distribution of biodiesel fuel were compared with the results of conventional diesel fuel by using spray visualization system composed of Ar-ion laser, ICCD camera and phase Doppler particle analyzer (PDPA) system. The combustion and exhaust emission characteristics of biodiesel fuel were studies using common-rail diesel engine with four cylinders. For the biodiesel blended fuel, it was revealed that higher injection pressure is needed to achieve the same injection rate at the higher mixing ratio. The spray tip penetration of biodiesel fuel was much the same with those of diesel. The atomization characteristics of biodiesel were inferior to conventional diesel fuel due to high viscosity and surface tension. The peak combustion pressures of both fuels were increased with advanced injection timing and the combustion pressure of biodiesel fuel is higher than that of diesel fuel. As the pilot injection timing is advanced to the TDC, the dissimilarities of both fuels combustion pressure are reduced. It can be also founded that the pilot injection can enhance the deteriorated spray and combustion characteristics of biodiesel fuel caused by physical fuel properties.

A phenomenological combustion analysis of a dual-fuel natural-gas diesel engine

2016 ◽  
Vol 231 (1) ◽  
pp. 66-83 ◽  
Author(s):  
Shuonan Xu ◽  
David Anderson ◽  
Mark Hoffman ◽  
Robert Prucka ◽  
Zoran Filipi
Keyword(s):  
Diesel Engine ◽  
Natural Gas ◽  
Heat Release ◽  
Diesel Fuel ◽  
Fuel Injection ◽  
Dual Fuel ◽  
Injection Timing ◽  
Heavy Duty ◽  
Engine System ◽  
Wiebe Function

Energy security concerns and an abundant supply of natural gas in the USA provide the impetus for engine designers to consider alternative gaseous fuels in the existing engines. The dual-fuel natural-gas diesel engine concept is attractive because of the minimal design changes, the ability to preserve a high compression ratio of the baseline diesel, and the lack of range anxiety. However, the increased complexity of a dual-fuel engine poses challenges, including the knock limit at a high load, the combustion instability at a low load, and the transient response of an engine with directly injected diesel fuel and port fuel injection of compressed natural gas upstream of the intake manifold. Predictive simulations of the complete engine system are an invaluable tool for investigations of these conditions and development of dual-fuel control strategies. This paper presents the development of a phenomenological combustion model of a heavy-duty dual-fuel engine, aided by insights from experimental data. Heat release analysis is carried out first, using the cylinder pressure data acquired with both diesel-only and dual-fuel (diesel and natural gas) combustion over a wide operating range. A diesel injection timing correlation based on the injector solenoid valve pulse widths is developed, enabling the diesel fuel start of injection to be detected without extra sensors on the fuel injection cam. The experimental heat release trends are obtained with a hybrid triple-Wiebe function for both diesel-only operation and dual-fuel operation. The ignition delay period of dual-fuel operation is examined and estimated with a predictive correlation using the concept of a pseudo-diesel equivalence ratio. A four-stage combustion mechanism is discussed, and it is shown that a triple-Wiebe function has the ability to represent all stages of dual-fuel combustion. This creates a critical building block for modeling a heavy-duty dual-fuel turbocharged engine system.

Investigations on performance of diesel engine by varying injection timings with design modification on piston crown

2018 ◽  
Vol 15 (5) ◽  
pp. 562-566
Author(s):  
Vijaya K. ◽  
Shailesh Palaparty ◽  
Raghavan Srinivasa ◽  
Ravi Kumar Puli
Keyword(s):  
Diesel Engine ◽  
Injection Pressure ◽  
Combustible Mixture ◽  
Injection Timing ◽  
Connecting Rod ◽  
Design Modification ◽  
Content Type ◽  
Piston Head ◽  
Piston Crown ◽  
Fuel Vaporization

Purpose Investigations are carried out with the aim of improving performance of a diesel engine with the design modification on piston crown to stimulate the uniform combustion by inducing turbulence in the incoming charge. Design/methodology/approach A stirrer is introduced at the top of the piston so as to inculcate more turbulence to the incoming charge by improving the rate of fuel vaporization. Whirling motion is created in the combustible mixture by providing rotating blades on the cavity/bowl of the reciprocating piston head. By putting a simple link mechanism, the oscillatory motion of connecting rod will rotate the blade by an angle of 60°. Findings The investigations are carried out with and without swirl piston at 17.5 compression ratio and 200 bar injection pressure by varying injection timings. Originality/value Finally, the result shows that by using the modified piston, nearly 3 per cent of efficiency increased and 31 per cent of NOx emissions are reduced compared to that of a normal piston with 80 per cent load at standard injection timing.

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