Efficiency of diesel operation on biofuels

2020 ◽  
Vol 919 ◽  
pp. 062010
Author(s):  
V A Likhanov ◽  
A V Fominykh ◽  
V N Kopchikov
Keyword(s):  
Diesel Operation

The impact of water injection and exhaust gas recirculation on combustion and emissions in a heavy-duty compression ignition engine operated on diesel and gasoline

2019 ◽  
Vol 21 (8) ◽  
pp. 1555-1573 ◽  
Author(s):  
Michael Pamminger ◽  
Buyu Wang ◽  
Carrie M Hall ◽  
Ryan Vojtech ◽  
Thomas Wallner
Keyword(s):  
Thermal Efficiency ◽  
Water Injection ◽  
Combustion Process ◽  
Exhaust Gas Recirculation ◽  
Exhaust Gas ◽  
Brake Thermal Efficiency ◽  
Fuel Ratio ◽  
Main Injection ◽  
Gas Recirculation ◽  
Diesel Operation

Steady-state experiments were conducted on a 12.4L, six-cylinder heavy-duty engine to investigate the influence of port-injected water and dilution via exhaust gas recirculation (EGR) on combustion and emissions for diesel and gasoline operation. Adding a diluent to the combustion process reduces peak combustion temperatures and can reduce the reactivity of the charge, thereby increasing the ignition-delay and, allowing for more time to premix air and fuel. Experiments spanned water/fuel mass ratios up to 140mass% and exhaust gas recirculation ratios up to 20vol% for gasoline and diesel operation with different injection strategies. Diluting the combustion process with either water or EGR resulted in a significant reduction in nitrogen oxide emissions along with a reduction in brake thermal efficiency. The sensitivity of brake thermal efficiency to water and EGR varied among the fuels and injection strategies investigated. An efficiency breakdown revealed that water injection considerably reduced the wall heat transfer; however, a substantial increase in exhaust enthalpy offset the reduction in wall heat transfer and led to a reduction in brake thermal efficiency. Regular diesel operation with main and post injection exhibited a brake thermal efficiency of 45.8% and a 0.3% reduction at a water/fuel ratio of 120%. The engine operation with gasoline, early pilot, and main injection strategy showed a brake thermal efficiency of 45.0% at 0% water/fuel ratio, and a 1.2% decrease in brake thermal efficiency for a water/fuel ratio of 140%. Using EGR as a diluent reduced the brake thermal efficiency by 0.3% for diesel operation, comparing ratios of 0% and 20% EGR. However, a higher impact on brake thermal efficiency was seen for gasoline operation with early pilot and main injection strategy, with a reduction of about 0.8% comparing 0% and 20% EGR. Dilution by means of EGR exhibited a reduction in nitrogen oxide emissions up to 15 g/kWh; water injection showed only up to 10 g/kWh reduction for the EGR rates and water/fuel ratio investigated.

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.

scholarly journals Experimental Investigation Of Biogas-Biodiesel Dual Fuel Combustion In A Diesel Engine

2015 ◽  
Vol 13 (1) ◽  
pp. 12-20 ◽  
Author(s):  
D. K. Ramesha ◽  
Adhiviraj Singh Bangari ◽  
Chirag P. Rathod ◽  
Chaitanya R. Samartha
Keyword(s):  
Peak Pressure ◽  
Maximum Load ◽  
Dual Fuel ◽  
Algae Biodiesel ◽  
Mode Of Operation ◽  
Pilot Fuel ◽  
Dual Fuel Combustion ◽  
Smoke Opacity ◽  
Co Concentrations ◽  
Diesel Operation

Abstract This study is an attempt at achieving diesel fuel equivalent performance from diesel engines with maximum substitution of diesel with renewable fuels. In this context the study has been designed to analyze the influence of B20 algae biodiesel as a pilot fuel in a biodiesel biogas dual fuel engine, and results are compared to those of biodiesel and diesel operation at identical engine settings. Experiments were performed at various loads from 0 to 100 % of maximum load at a constant speed of 1500 rpm. In general, B20 algae biodiesel is compatible with diesel in terms of performance and combustion characteristics. Dual fuel mode operation displays lower thermal efficiency and higher fuel consumption than for other fuel modes of the test run across the range of engine loads. Dual fuel mode displayed lower emissions of NOx and Smoke opacity while HC and CO concentrations were considerably higher as compared to other fuels. In dual fuel mode peak pressure and heat release rate were slightly higher compared to diesel and biodiesel mode of operation for all engine loads.

Performance of a direct injection diesel engine fuelled with a dimethyl ether/diesel blend

2003 ◽  
Vol 217 (9) ◽  
pp. 819-824 ◽  
Author(s):  
Wang Hewu ◽  
Zhou Longbao
Keyword(s):  
Diesel Engine ◽  
Dimethyl Ether ◽  
Engine Speed ◽  
Direct Injection ◽  
Test Results ◽  
Di Diesel Engine ◽  
Hc Emissions ◽  
Blend Fuel ◽  
Co Emission ◽  
Diesel Operation

A quantity of 10 per cent dimethyl ether (DME) was added to diesel fuel, and an investigation of the performance of a direct injection (DI) diesel engine fuelled with blend fuel was carried out. The test results showed that, in comparison with diesel operation, the torque at low engine speed was increased; the brake specific fuel consumption (b.s.f.c.) with speed characteristics at full load was reduced by 20 g/kW h on average; the smoke was reduced significantly, and the coeffcient of light absorption of smoke decreased by 50 per cent; the NOx and HC emissions were also clearly reduced, and the CO emission was at the same level as that of a diesel engine.

The Advanced Injection Low Pilot Ignited Natural Gas Engine: A Combustion Analysis

2003 ◽  
Author(s):  
Kalyan K. Srinivasan ◽  
Sundar R. Krishnan ◽  
Sabir Singh ◽  
K. Clark Midkiff ◽  
Stuart R. Bell ◽  
...  
Keyword(s):  
Natural Gas ◽  
Natural Gas Engines ◽  
Natural Gas Engine ◽  
Unburned Hydrocarbon ◽  
Full Load Operation ◽  
Dual Fuel Engines ◽  
Engine Stability ◽  
Hc Emissions ◽  
Conversion Efficiencies ◽  
Diesel Operation

The Advanced Low Pilot Ignited Natural Gas (ALPING) engine is proposed as an alternative to diesel and conventional dual fuel engines. Experimental results from full load operation at a constant speed of 1700 rev/min are presented in this paper. The potential of the ALPING engine is realized in reduced NOx emissions (less than 0.2 g/kWh) at all loads accompanied by fuel conversion efficiencies comparable to straight diesel operation. Some problems at advanced injection timings are recognized in high unburned hydrocarbon (HC) emissions (25 g/kWh), poor engine stability reflected by high COVimep (about 6 percent), and tendency to knock. This paper focuses on the combustion aspects of low pilot ignited natural gas engines with particular emphasis on advanced injection timings (45°–60°BTDC).

In-Cylinder Production of Hydrogen During Net-Lean Diesel Operation

2006 ◽  
Author(s):  
Brian West ◽  
Shean Huff ◽  
James Parks ◽  
Matt Swartz ◽  
Ron Graves
Keyword(s):  
Production Of Hydrogen ◽  
Diesel Operation

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.

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.

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.

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