Papers by Keyword: Emission

Abstract: Compression ignition engines with ethyl alcohol as a fuel are associated with some problems. Because of ethyl alcohol has high self-ignition temperature. It can be used in compression engine by hot surface ignition method which is used to resolve the ignition of the fuel. The modification of the engine is carried out in such a way that a pre combustion chamber is designed in engine head with a provision for heat plug is made on the pre combustion chamber. A piston with squish plate is designed and thermally analyzed. The squish piston helps for attaining better homogeneous mixture than conventional piston. Thus the better combustion is obtained with the squish piston resulting with higher adiabatic flame temperature than the conventional piston. When air is inducted into the combustion chamber it is exposed to high temperature. Modifications for pure ethyl alcohol made significant improvement in thermal efficiency, torque and reduction in specific fuel consumption of an engine. The results exhibit a path toward ethyl alcohol has an effective alternative to conventional diesel engines.

Abstract: Effect of preheat intake air were investigated on performance and emission characteristic of a compression ignition engine running on fuel of diesel (70%)-ethanol (30%). Fuel was evaluated within the engine twist with intake air temperature at 30°C and 60˚ respectively. Performance and emission characteristic of the diesel engine are compared based on diesel-ethanol blend, with and without preheat. The resulting emission indicated that the high heat of vaporization of ethanol affect CO and HC emission considerably. Preheating the intake air diesel-ethanol blend tends to reduce the production of CO and HC whereas increasing NOx emission.

Abstract: Vegetable oils are a potential alternative to partial or total substitution of diesel fuels. In this study, we used diethyl ether as an additive to investigate the possible use of increased percentages of biodiesel in diesel engine without any retrofitting. Biodiesel was made by pyrolysis process. Cashew nut shell liquid (CNSL) was selected for biodiesel production. Number 2 diesel fuel containing 20% biodiesel and 80% diesel fuel, is called here as B20. The effects of diethyl ether, blended with B20 in 5, 10, 15 % by volume were used in a single cylinder, four strokes direct injection diesel engine. The effect of test fuels on engine torque, power, brake specific fuel consumption, brake thermal efficiency, exhaust gas temperature, were ascertained by performance tests. The influence of blends on CO, CO₂, HC, NO and smoke opacity were evaluated by emission tests. The experimental results showed that the exhaust emissions were fairly reduced for 10% diethyl ether with B20; especially the NO is reduced remarkably by 69.4% while comparing B20.

Abstract: Biofuels are renewable, nontoxic and ecofriendly fuels that can play an important role in automobile industries. They can successfully replace diesel fuel and helps in decreasing the import of crude oil. The discarded seed of Calophyllun Inophyllum which are planted in India mainly to prevent soil erosion is considered as the possible source for extracting biodiesel. The tamanu oil extracted had a fatty acid value of 48 mg KOH/g, therefore a two stage esterification processes with acid and base catalyst were used for converting it into biodiesel. The fuel was then tested for properties such as viscosity, calorific value and carbon residue using standard test procedures and found to be analogous with diesel, which makes it possible to use this alternate fuel in the existing engine without any modification. A single cylinder, four stroke, constant speed, variable compression ratio, direct injection diesel engine developing 5KW power with provision for computerized data acquisition is used to evaluate the performance and emission characteristics. The test results were analyzed for biodiesel and its blends in comparison with standard diesel at different compression ratios (16:1, 18:1, 20:1 & 22:1). The performance and emission results of the diesel engine revealed that biodiesel can be blended with diesel up to 40% at an optimum CR of 20, in order to get improved performance and reduced emission.

Abstract: Depletion of fossil fuels, unaffordability of conventional fuels (petrol, diesel) and atmospheric pollution lead researchers to develop alternative fuels. Fuels derived from renewable biological resources used in diesel engines are known as biodiesel. Biodiesel is environmental friendly liquid fuel similar to petrol and diesel in combustion properties. Increasing environmental concern, diminishing petroleum reserves and agriculture based economy of our country are the driving forces to promote biodiesel as an alternate fuel. Hydrogen seems to be viable fuel to meet sustainable energy demand with minimum environmental impact. Hydrogen has high calorific value and clean burning characteristics which makes it effective fuel for future. It was found that hydrogen usage reduce emissions such as CO₂ and HC. India is one of the largest producers of neem oil and its seed contains 30% oil content. It is an untapped source in India, so the neem oil usage will be a best option. The investigation made on pure neem oil and neem oil with hydrogen addition at different flow rate (2 lpm & 4 lpm) in CI engines. The result shows that, brake thermal efficiency of neem oil with 4 lpm hydrogen was increased to 7.98% compare to pure neem oil at 4 Nm torque and fuel consumption of neem oil with 4 lpm hydrogen was decreased to 13.49% compared to pure neem oil at 4 Nm torque.

Abstract: Nerium methyl ester, an esterified biofuel, has an excellent cetane number and a reasonable calorific value. It closely resembles the behaviour of diesel. However, being a fuel of different origin, the standard design limits of a diesel engine is not suitable for Nerium methyl ester (NME). Therefore, in this work, a set of design and operational parameters are studied to find out the optimum performance of Nerium methyl ester run diesel engine. This work targets at finding the effects of the engine design parameter viz. fuel injection pressure (IP) on the performance with regard to specific fuel consumption (SFC), brake thermal efficiency (BTHE) and emissions of CO, CO₂, HC, NO_x with N20 as fuel. Comparison of performance and emission was done for different values of injection pressure to find best possible condition for operating engine with NME. For small sized direct injection constant speed engines used for agricultural applications, the optimum injection pressure was found as 240bar.Methyl esters from Nerium, with properties close to diesel; show better performance and emission characteristics. Hence Nerium (N20) blend can be used in existing diesel engines without compromising the engine performance. Diesel (25%) thus saved will greatly help the interests of railways in meeting the demand for fuel,as diesel trains are operated at maximum load condition.

Abstract: Increased demand and production in all segments of the automotive industry has driven the nation to impose stringent emission norms for automobile engines. At this juncture, bio-diesel has sufficient attraction as vehicular fuel. But the properties of bio-diesels are not the same as diesel fuels, including high viscosity and low volatility. Due to this inherent problem it exhibits poor atomization, which results in incomplete combustion and increased exhaust emissions. This naturally implies that automotive designers have to focus their research more on engine emissions while at the same time not compromising on power development. This has put enormous pressure on automotive industry to design the engine efficiently and economically to compete with the global market. This paper relates the modification of engine combustion chamber design, for inducing turbulence to improve the combustibility of combustible mixture of karanja bio-diesel and to reduce the exhaust emissions. The modification includes the tri-chambered piston and twisting blade pistons. In the present work the emission characteristics of modified piston engine are compared with the standard piston engine. It was observed that the CO and UBHC emissions can be effectively reduced with tri-chambered piston engine.

Abstract: LPG is a mixture of gas, mainly propane and butane. It is commonly used as a fuel for cooking and as a transportation fuel. It is normally created as a by-product of petroleum refining and from the production of Natural Gas. An experiment is conducted to obtain the operating characteristics of the four stroke three cylinder inline water cooled spark ignition engine operated with LPG and methanol. The engine is started with LPG and methanol with various ratios at constant volume rate in the vaporizer. Solenoid valve was used to allow either LPG or petrol in the carburetor. The LPG supplied through the vaporizer and the quantity is metered by hanging type weighing scale. The additives are added with LPG before supplied to the vaporizer. The performance characteristics of engine were analyzed using petrol with increase in load. Further the engine run with LPG and adjusts the flow based on the mixing of additives. The best ratio of additives can be selected based on the experimental results obtained in the engine.The findings of the present research work suggest that optimum % of methanol as additive to increase the overall performance and to reduce the emission levels.

Abstract: The present study investigates the effect of air-side oxygen concentration enrichment on the performance and emission of a single cylinder diesel engine using a bio-fuel blend as fuel. In this study, a natural phenolic compound, namely, cardanol is selected as the bio-fuel, which is obtained from the shell of cashew nut after purification. A blend of B10M10 (10% cardanol +10% methanol + 80% diesel by volume) is prepared and tested in the engine at various loading conditions. The experiments are carried out at atmospheric oxygen condition and an increment of 3, 5, and 7% of atmospheric oxygen concentration by weight. There is a drastic reduction in HC, CO, and smoke except for NOx emission. The level of NOx emission increases as the oxygen concentration in the intake air is increased. The performance characteristic will increase as the oxygen concentration increases, and higher brake thermal efficiency is obtained for B10M10 at 7% oxygen concentration. B10M10 with 7% oxygen enrichment gives better results, similar to diesel, except for NOx emission.

Abstract: An experimental investigation on the performance, emission and combustion characteristics of single cylinder water cooled diesel test engine was carried out at a constant speed of 1500 rpm with processed waste engine oil. The experiments were carried out at different load conditions from no load to 110% load. To compare the results obtained the baseline readings were taken with diesel. The standard operating condition of the engine was 200 bar injection pressure and 23° before Top Dead Center (bTDC). For processed Waste Engine Oil (pWEO) fuel operation the Brake Thermal Efficiency (BTE) obtained at rated load point was 32.18 %. at 100 % load and pWEO gave a peak pressure of 64.46 bar compared to 66.12 bar for diesel. There was a 5 % reduction in the Nitrous Oxide (NO) emission with pWEO. Heat release rate (HRR) and exhaust gas temperature showed considerable reduction with pWEO fuel operation.