Applied Mechanics and Materials Vol. 787

Abstract: This paper investigates the performance and emission characteristics of 20% cashew nut shell liquid (CNSL)-diesel blend (B20) in a direct injection diesel engine. The cashew nut shell liquid was prepared by pyrolysis method. The test was conducted with various nozzle opening pressures like 200 bar, 225 bar and 250 bar at different loads between no load to full load. The results showed that the brake thermal efficiency was increased by 2.54% for B20 with 225 bar at full load. The CO and smoke emissions were decreased by 50% and 14% respectively and the NOx emission were decreased slightly with 225 bar injection pressure compared with 200 bar and 250 bar at full load. On the whole, it is concluded that the B20 CNSL blend can be effectively used as a fuel for diesel engine with 225 bar injection pressure without any modifications.

Abstract: This paper presents the experimental work to investigate the effect of Re-entrant and Toroidal combustion chambers in a DICI Engine. The two combustion chambers namely Re-entrant combustion chamber (RCC) and Toroidal combustion chamber (TCC) were fitted in a 4.4 kW single cylinder Direct Injection Compression Ignition (DICI) engine and tests were conducted with diesel. The influences of the combustion chamber geometry characteristics on combustion, performance and emissions characteristics have been investigated. This investigation shows the peak pressure of re-entrant chamber is higher than that of toroidal chamber. The heat release rate and brake thermal efficiency for re-entrant chamber are slightly higher than that of toroidal chamber. Specific fuel consumption is lower for toroidal chamber than that of re-entrant chamber. The enhancement in reduction of carbon monoxide, hydrocarbon is observed for Re-entrant chamber compared to the Toroidal chamber. Oxides of nitrogen are reduced for toroidal chamber than that of re-entrant chamber.

Abstract: The experimental investigation has been carried out to study the stabilization and blowout mechanisms of turbulent flame stabilized by V-gutter bluff body in a square duct at reactive and non-reactive conditions. V-shaped bluff bodies made of stainless steel having 1.6 mm thicknessare used for stabilization of the flame.Experiments have been conducted at selective velocities of commercially available methane and oxygen with 60 degree V-gutter as flame holder. It is observed that at stoichiometric conditions, the V-gutter is dominated by shear layer stabilized flames. The flame stability is influenced by bluff body dimensions and mass flow rate which play a major role in combustion instabilities mixing of air fuel ratio and blow off. The lift off decreases at higher blockage ratios.A strong recirculation zone is found in this test rig immediately downstream of the V-Gutter which gradually subsides and disappears far downstream.The lift off height is not much affected by the velocity of the fuel-air mixture.

Abstract: Diffusion flame burners are mainly used in industries over premixed flame burners for safety considerations. But the combustion process in a diffusion flame is not complete and the flame is usually in bright yellow in colour in contrast to the premixed flame which gives a bluish flame. To improve the combustion process in a diffusion flame burner a novel approach, using chevrons has been carried out. The chevrons are found to reduce the aero-acoustic noise in the exhaust jets of aircraft engines by allowing better mixing of the exhaust gas with the ambient air. The similar concept is used here where the tips of the burners are cut in the form of chevrons. Experimental investigations are carried out on burners with three and four chevrons in addition to a standard burner using LPG as the fuel. The results indicate that with the introduction of chevrons the diffusion flame becomes more compact. The premixed region, in the diffusion flame, where the air and fuel is mixed well is found to increase by nearly 100 % with the usage of chevrons, indicating better mixing of fuel and air. The results also indicate that increasing the number of chevrons from three to four does not show much variation. Further experiments are to be carried out to determine the improved fuel consumption with the usage of chevrons.

Abstract: Ever increasing cost of petroleum products demands more research in the area of new and alternate energy including solar, wind, biofuel and hybrid energy systems. Vegetable oil methyl ester is one of the promising alternate fuels that can be used as a substitute for diesel in the countries that are cultivating more agricultural products. In the present work, the analysis of physical properties such as calorific value, viscosity, flash and fire point temperatures of Sunflower oil methyl Ester have been made. The sunflower methyl ester has been prepared by transesterification process from pure sunflower oil in the presence of methanol and NaOH. Further, property enhancement of sunflower oil methyl ester has also been made by adding different additives such as ethanol and Di-Ethyl Ether in various proportions. Sunflower oil Methyl Ester (SME) with 1%, 3%, 5% ethanol or Di-Ethyl Ether and mixture of (Ethanol and DI-Ethyl Ether) has been analysed for the fuel properties. The investigation shows that the flash and fire point temperatures and viscosity of sunflower methyl ester decrease with increasing the additives. The calorific value of 20 percent biodiesel blend (B20) of SME with 5% Ethanol additive is very close to that of diesel.

Abstract: The paper presents an experimental investigation, to evaluate the performance and emission characteristics of a direct injection diesel engine using diesel-ethanol blends with aqueous cerium oxide nano fluid (ACN) as additive at different load conditions. The test fuel (D85E15ACN) prepared using ultrasonic sonicator, contains diesel 85%, ethanol 15% (D85+E15) by volume, with 1ml of aqueous cerium oxide nanofluid (ACN) added with the blend. The results show that, when the engine is run with D85E15ACN, there is an increase in brake thermal efficiency and reduction in hydrocarbon (HC), carbon monoxide (CO) and smoke emissions, compared to that of neat diesel.However, nitric oxide (NO) emission are more for D85E15ACN.

Abstract: Cashew nut shell oil (CNSO) is potential alternative fuel for diesel engine. Its drawback is incomplete combustion and low brake thermal efficiency (BTE) due to high viscosity. To overcome this problem the CNSO was blended with diethyl ether (DEE) which is less viscous and burns easily. The influence of blends on CO, NOx and smoke emission is investigated by emission tests. The fuel containing 20% CNSO and 80% diesel fuel (B20), 95% B20 and 5% DEE by volume (B20D5), 90% B20 and 10%DEE by volume (B20D10) 85% and B20 and 15% DEE by volume (B20D15) are tested. Initially the experiment was conducted with different blends of CNSO-diesel blends like 10%, 20%, & 30% by volume basis in a diesel engine.The aim for the research of alternative fuel is to replace the sufficient amount of diesel fuel without affecting the existing engine performances. Increasing CNSO diesel blends performances reduces marginally. B10 shows more closer performances to diesel fuel, but replacement of 10% only diesel is not much. Using B30 and higher blends gives poor result. Hence it was decided to be B20. In the second stage B20 as a base fuel and it is blended with DEE 5%, 10% & 15% by volume basis at different load conditions. The result shows that B20D15 has BTE 26.50% which is very close to the base diesel fuel. The B20D15 emits 1200 PPM of NOx while diesel emits 1195 PPM but B20 emits 1450 PPM of Nox. Carbon monoxide (CO) emission also reduces for different blends of DEE. The smoke emission is 3.96, 3.38, 3.15 FSN of B20, B20 D15 and diesel respectively.

Abstract: The use of fossil fuel is increasing drastically due to its consumption in all consumer activities. The utility of fossil fuel depleted its existence, degraded the environment and led to reduction in underground carbon resources. Hence the search for alternative fuels is paying attention for making sustainable development, energy conservation, efficiency and environmental preservation. The worldwide reduction of underground carbon resources can be substituted by the bio-fuels. The researchers around the world are finding the alternate fuel that should have the least impact on the environment degradation. This paper aims at finding an alternative for diesel and reducing the pressure on its existing demand. This study aimed at using two types of oil mixtures namely cashew nut shell oil and camphor oil mixed with diesel, turpentine oil mixed with diesel in different proportions as fuel in twin cylinder four stroke diesel engine. Performance and emission analysis have been performed by using exhaust gas analyzer in the oil samples. It was observed that 40% cashew nut shell oil and 10%camphor oil mixed with 50% diesel, 50% turpentine oil mixed with 50% diesel shows the better engine performance and also less emissions.

Abstract: Alternative fuel source such as ethanol possess great potential to replace conventional fuels such as petrol and diesel. There has been a great increase in the usage of such fuels in the developing world, of late, with many countries having already mandated the usage of ethanol blended petrol. In developing countries, two stroke internal combustion engines continue to be used for powering agricultural implements and auto rickshaws. This paper presents the experimental investigations carried out on the usage of petrol blended with different proportions of ethanol by volume (5%, and 10%) as a fuel for an unmodified and used 100cc two stroke SI engine. The objectives of the experimental investigations are to determine whether ethanol blended petrol can be used as a suitable fuel for the commonly used two stroke internal combustion engine without any modifications. Tests were carried out on the engine, with petrol as the fuel initially and then with ethanol blended petrol with increasing proportion of ethanol. The total fuel consumption rate seemed to increase upon addition of ethanol. However, the brake specific fuel consumption remained fairly constant. The fact that brake specific fuel consumption varies only marginally indicate that ethanol can be used as a substitute for petrol, as a fuel.

Abstract: Many studies have confirmed that the use of transesterifed vegetable oil as a fuel in diesel engine has resulted in lesser efficiency and inferior combustion rate when compared with petroleum diesel. Of late research works are being carried out to discover the surplus information on effective utilization of vegetable oil in CI engine as a promising alternative fuel. The present work was aimed to investigate the effect of preheating the transesterified oil just before entering fuel injection system thereby making its physical and chemical properties much closer to diesel fuel. In the present work neat mustard oil methyl ester was preheated to 90°c (MO90) and used in single cylinder, four stroke, naturally aspirated, direct injection compression ignition engine and compared with un heated mustard oil methyl ester (MO) at ambient temperature and petroleum diesel. The effects of fuel preheating on engine performance with mustard oil were clarified. Experiments were conducted with MO90 (Mustard oil methyl ester preheated to 90° C) and MO (Mustard oil methyl ester) and are compared with conventional diesel. The experimental analysis revealed that the BTE (brake thermal efficiency) of an engine was lower and BSFC (brake specific fuel consumption) was higher with unheated mustard oil methyl ester as compared to diesel fuel. However, increase in BTE and reduction in BSFC was observed with increase fuel inlet temperature of methyl ester to 90°C. Thus by preheating the mustard oil methyl ester during the fuel injection can be a good alternate fuel for CI engines in near future.