Shailendra Sinha

Effect of EGR on the exhaust gas temperature and exhaust opacity in compression ignition engines

In diesel engines, NOx formation is a highly temperature-dependent phenomenon and takes place when the temperature in the combustion chamber exceeds 2000 K. Therefore, in order to reduce NOx emissions in the exhaust, it is necessary to keep peak combustion temperatures under control.One simple way of reducing the NOx emission of a diesel engine is by late injection of fuel into the combustion chamber. This technique is effective but increases fuel consumption by 10–15%, which necessitates the use of more effective NOx reduction techniques like exhaust gas recirculation (EGR). Re-circulating part of the exhaust gas helps in reducing NOx, but appreciable paniculate emissions are observed at high loads, hence there is a trade-off between NOx and smoke emission. To get maximum benefit from this trade-off, a paniculate trap may be used to reduce the amount of unburnt particulates in EGR, which in turn reduce the paniculate emission also.An experimental investigation was conducted to observe the effect of exhaust gas re-circulation on the exhaust gas temperatures and exhaust opacity. The experimental setup for the proposed experiments was developed on a two-cylinder, direct injection, air-cooled, compression ignition engine. A matrix of experiments was conducted for observing the effect of different quantities of EGR on exhaust gas temperatures and opacity

Experimental Investigation of the Effect of Biodiesel Utilization on Lubricating Oil Degradation and Wear of a Transportation CIDI Engine

Increased environmental awareness and depletion of fossil petroleum resources are driving industry to develop alternative fuels that are environmentally more acceptable. Biodiesel is an alternative fuel derived from vegetable oils by modifying its molecular structure. In the present experimental research work, methyl ester of rice-bran oil (ROME) is derived through transesterification of rice-bran oil using methanol in presence of sodium hydroxide (NaOH) catalyst. On the basis of previous research for performance, emission and combustion characteristics, a 20% blend of ROME (B20) was selected as optimum biodiesel blend. In the present research, the experimental investigation was aimed to investigate the effect of biodiesel on wear of in-cylinder components. Endurance tests were conducted on a medium duty direct injection transportation diesel engine with 20% blend of the ROME with mineral diesel. Tests were conducted under predetermined loading cycles in two phases: engine operating on mineral diesel and engine fuelled with 20% biodiesel blend. After completion of the tests, engines were dismantled for observing the physical condition of the various parts, e.g. piston rings, bearings, cylinder liner, cylinder head etc. Physical measurements of various vital parts were also carried out to assess the wear of the parts of engine. The physical wear of various parts except big end bearings were found to be lower in case of 20% biodiesel fuelled engine. Wear metals in the lubricating oil samples drawn from the engines at regular intervals were investigated. Relatively lower wear concentration of all wear metals except lead were found in the lubricating oil of B20 fuelled engine. Two quantify the wear of cylinder liners, surface parameters at different locations in the liner (TDC, BDC and mid-stroke) were measured and investigated. A qualitative analysis was also carried out by taking surface profiles and conducting scanning electron microscopy at same locations.Copyright

Performance Evaluation of a Biodiesel (Rice Bran Oil Methyl Ester) Fuelled Transport Diesel Engine

This experimental study was undertaken to investigate the use of vegetable oil derivatives to substitute mineral diesel fuel. Straight vegetable oils pose some problems like injector coking, carbon deposits etc., when used as a fuel in an engine. These problems are due to high viscosity, low volatility and polyunsaturated character of vegetable oils. Transesterified vegetable oil derivative called “biodiesel” appear to be most convenient way of utilizing vegetable oil as a substitute fuel in diesel engines. In present investigation, rice bran oil (non-edible) was transesterified to methyl ester and reaction conditions for transeterifcation process for rice bran oil were optimized. Various properties like viscosity, density, flash point of the biodiesel thus prepared are comparable to diesel and found to be in acceptable range as per ASTM norms (ASTM D6751). Experimental investigations were carried out on a four stroke, four cylinders, transportation DI diesel engine. Various blends of biodiesel (rice bran methyl ester) and diesel ranging from 5% to 50% ester in the blend were used for performance and emission test in the transport diesel engine and the results are compared with the baseline data obtained using mineral diesel. Detailed engine tests show that biodiesel can be used as partial substitute fuel in existing diesel engines without substantial hardware modification and it significantly lower the emissions of harmful species from diesel engines without jeopardizing the engine performance.

Rice bran oil methyl ester fuelled medium-duty transportation engine : long-term durability and combustion investigations

Increased environmental awareness and depletion of resources are driving industry to develop alternative fuels that are environmentally more acceptable. In present investigation, biodiesel from rice bran oil is developed and characterised as per ASTM D6751 and found to be comparable with mineral diesel. Steady state engine dynamometer tests have been carried out to evaluate the performance and emission characteristics (ECE R49 test cycle) of a medium duty transportation direct injection diesel engine fuelled with various biodiesel blends ranging from B00 to B100. Combustion characteristics of the same engine running with diesel, biodiesel and B20 (20% biodiesel) blend have been investigated. In addition, endurance tests were conducted under predetermined loading cycles in two phases: engine operating on mineral diesel and engine fuelled with B20 blend. To quantify the wear of cylinder liner, surface parameters and scanning electron microscopy (SEM) at different location in the liner were done. Wear metal analysis and ferrography of lubricating oil samples drawn from both phase of engine operation were also carried out.

Ricebran Oil Biodiesel's Performance, Emission and Endurance Test on a CIDI Transport Engine

Increased environmental awareness and depletion of resources are driving industry to develop alternative fuels that are environmentally more acceptable. Fatty acids esters (biodiesel) are known to be good alternative fuels. Due to economic reasons, the use of cheap raw materials for biodiesel production is preferred. In this case, ricebran oil, non-edible grade is used. Base catalyzed transesterification of ricebran oil is investigated and process parameters for ricebran biodiesel production are optimized. Various properties like viscosity, density, flash point, calorific value of biodiesel thus prepared are characterized as per ASTM D6751 and found comparable to mineral diesel. Steady state engine dynamometer test at 1800 rpm has been carried out to evaluate the performance and emission characteristics of a medium duty transportation DI diesel engine. Emission tests with all the fuel blends have also been carried out using European 13 MODE test (ECE R49). Experimental investigations have been carried out to examine the combustion characteristics in a direct injection transportation diesel engine running with diesel, biodiesel (rice-bran oil methyl ester), and its blends. Endurance tests were conducted with 20% blend of the ROME with mineral diesel. Tests were conducted under predetermined loading cycles in two phases: engine operating on mineral diesel and engine fuelled with 20% biodiesel blend. To quantify the wear of cylinder liner, surface parameters and scanning electron microscopy at different location in the liner (TDC, BDC and mid stroke) were done and investigated. A qualitative analysis was also carried out by taking surface profiles at same locations.

Experimental Investigation on the Performance and Emission Characteristics of Direct Injection Medium Duty Transport Diesel Engine Using Rice-Bran Oil Biodiesel

Over the past several years, there has been increased interest in alternative diesel fuels to control emissions and provide energy security. Biodiesel is a fuel that can be made from renewable biological sources such as vegetable oils and animal fats, has been recognized as an environment friendly alternative to mineral diesel. In present investigation, rice bran oil (non-edible) was transesterified to methyl ester and reaction conditions for transesterifcation process for rice bran oil were optimized. Various properties like viscosity, density, flash point, calorific value of the biodiesel thus prepared are characterized as per ASTM norms (ASTM D6751) and found comparable to diesel. Steady state engine dynamometer test at full throttle conditions have been carried out to evaluate the performance and emission characteristics of a medium duty transportation DI diesel engine. Engine was fuelled with various blends of rice-bran oil biodiesel (ROME) and mineral diesel ranging from 5% biodiesel to 100% biodiesel (5, 10, 20, 30, 50, and 100%). Performance and emission data were compared to the baseline data obtained using mineral diesel. Same engine without any hardware modification has been adopted for tests on all fuel blends. The results of this experimental investigation showed that biodiesel and biodiesel blends exhibited almost similar torque and power characteristics. Biodiesel blends up to 20% produced slightly higher torque and improved performance. Improvement in fuel conversion efficiency was found for lower concentration blends i.e. up to 20%. Lowest efficiency was found for 100% biodiesel blend. All the biodiesel blends emitted lower total hydrocarbon, carbon monoxide emissions and smoke opacity but slightly higher NOx emissions during the full throttle tests. Emission tests with all the fuel blends have also been carried out using European 13 MODE test (ECE R49) procedure. Drastic reduction in THC and CO and slight increase in NOx was observed.© 2007 ASME