Advanced Materials Research Vols. 984-985

Abstract: This paper presents the results of the experimental investigation on a solar flat plate collector carried out at Coimbatore, India (11°N Latitude and 74°E Longitude). The collector tubes allowed the water to flow twice across the flat plate collector using a circulating pump during which the water gets heated by the solar radiation received by the absorber. The maximum temperature of water obtained on a typical day in the month of April was 64°C with a solar radiation of 932.2651 W/m². The available solar radiation strongly influences the temperature gain of the system while the wind velocity plays a considerable role in influencing the heat lost by the system. It is observed that the two-pass flow of water across the absorber plate results in a maximum temperature gain with an overall collector efficiency of 43.7 %. This solar water heating system using flat plate collector can be used for small-scale desalination applications.

Abstract: Linear Fresnel reflector solar concentrator technology is similar to solar trough technology in which the sunlight is reflected by a series of mirrors onto an absorber tube, thus linear F resnel reflector solar concentrator , is a linear line concentrator. The performance of the system depends on the design parameters, mass flow rate, etc. In the present work, by using MATLAB simulation program, a detailed design parameters analysis including the effect of variation in the height of the absorber, width of the absorber plane and the width of the reflector mirror elements on the concentration on the surface of the absorber plane has been made. The width of the absorber plane was investigated by using analytical and ray tracing technique s . Then, the optimized width of the absorber plane was used to design the absorber tubes. Also, detailed thermal performance analysis for the above design has been made. Results have been plotted graphically and discussed.

Abstract: In this paper, the implementation of Z-Source Inverter based on Maximum power point tracking scheme (MPPT) for photovoltaic (PV) System is employed. This proposed work has the advantage of more power yield with reduced switching elements in power conditioner. Also a single stage power conversion circuit possessing Z-source network which replaces the boost converter set up in conventional mundane maximum power tracking circuits. The maximum power tracking is the trickiest part which is embedded within the inverter control. Therefore the control over inverter not only operates the PV panel at its maximum possible power but also have a check at the capacitor voltage of the Z-source network, thereby making the system more reliable and power efficient.

Abstract: The methyl esters of vegetable oils known as biodiesel are fetching more and more attraction because of the low environmental impact and potential as a green alternative fuel for diesel engine and they would not require significant modification of existing engine. Methyl esters of Jatropha (JME) are derived through transesterification process. Experimental investigations have been carried out to examine properties, performance and emission of different blends of JME. Result indicated that B20 have closer performance to diesel. The use of these methyl esters gives lower smoke, CO and HC but the Nitrogen Oxide emission is more. However to reduce the Nitrogen Oxide emission in diesel and various vegetable oil esters by lowering the combustion chamber temperature, Electronic fuel injection method is adopted. The study was carried out in a single cylinder 8 H.P running at 1800 rpm using the diesel, JME by the method of normal and Electronic Fuel Injection system and the result are compared between them. The result indicates that the Nitrogen Oxide emission is less for Electronic fuel injection method than the single injection. This helps to lower the combustion chamber temperature considerably, and hence the chance of generating the Nitrogen Oxide is minimized compared to the single injection.

Abstract: In present scenario researchers focusing the alternate sources of petroleum products. Based on this, current research work focused the emission study of its characteristics and potential as a substitute for Diesel fuel in CI engines. Current research biodiesel is produced by base catalyzed transesterification of rice bran oil is known as Rice Bran Oil Methyl Ester (Biofuel). In this research various proportions of Biofuel and Diesel are prepared on volume basis. It is used as fuels in a four stroke single cylinder direct injection Diesel engine to study the performance and emission characteristics of these fuels. Varieties of results obtained, that shows around 50% reduction in smoke, 33% reduction in HC and 38% reduction in CO emissions. In result discussion a different blends of the brake power and BTE are reduced nearly 2 to 3% and 3 to 4% respectively around 5% increase in the SFC. Therefore it is accomplished from the this experimental work that the blends of Biofuel and Diesel fuel can successfully be used in Diesel engines as an alternative fuel without any modification in the engine. It is also environment friendly blended fuel by the various emission standards.

Abstract: The prediction of the performance of different biomass energy sources in gasifiers is an important area of study for the implementation of this technology in various applications, relevant to remote villages. This paper presents the experimental studies conducted on a 50 kW imbert downdraft gasifier with wood and rubber seed kernel which are available abundantly in villages close to hilly regions of South India. The influence of equivalence ratio on the species concentration, gas production rate, HHV of producer gas and gasifier conversion efficiency are discussed. The experimental study shows that the rubber seed kernel can be effectively used as feedstock in biomass gasifiers to meet the decentralized heat and power applications of rural villages.

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: The present work concerns with the evaluation of performance and emissions characteristics of CI engine using cottonseed based biodiesel (B20) with fuel additive N-butonal at different concentration levels. In the experimental work it was observed that addition of N-butonal as additive improved the performance of CI engine and reduced the emission levels of NOx, CO, HC. Tests were also conducted the effect of inlet air preheating and results shows the significant improvement in the engine performance and reduction in the emission levels. Better performance and emission levels observed when the engine runs at air inlet temperature of 60°C

Abstract: The research is aimed to optimise the engine parameters by using biodiesel as a fuel. Neem oil is used as a bio diesel in CI engine which is produced by transesterification process. Taguchi optimization technique was used to get optimum level of parameters such as brake thermal efficiency (BTHE), indicated thermal efficiency (ITHE) and specific fuel consumption (SFC). Experiments were conducted with neem oil biodiesel blends and diesel value were compared with these results and presented in this paper. The result clearly shows that blend B60, compression ratio 18:1 and 6 Kg load was the optimum parameters.Keywords: Neem biodiesel; CI engine; Performance; Taguchi technique;

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.