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Vortex generation has been emerged as one of the promising passive technique for improving air-side heat transfer performance of air cooled heat exchangers. It can be achieved by employing small flow turbulators, called vortex generators (VGs), which are installed on the heat transfer surface (fins). VGs can generate longitudinal vortices, which strongly disturb the flow structure, and have a significant influence on the velocity and temperature distributions, causing improved thermal transport. In this study, three dimensional numerical analyses have been carried out to examine the thermo-hydraulic performance of fin-and-tube heat exchangers (FTHE) by using rectangular winglet vortex generator (RWVG) with a circular punched hole. The augmentation in the performance of heat exchanger with RWVG having punched hole is established and compared with baseline case (without VG) by solving the Navier Stokes and energy equations with a Finite Volume Method in body fitted grids.

The main focus areas of today's IC engine design are energy efficiency and higher thermal efficiency. As there is a high amount of heat loss in atmosphere due to which the efficiency is lower for the standard engine. There is one possible solution to reduce such problem i.e., converting the conventional CI engine in to the LHR engine. For the current work the performance and emission characteristics are evaluated for the twin cylinder ceramic coated water cooled CI engine using blends of diesel and neem bio diesel. For the present work the bio-diesel was prepared in laboratory from non-edible vegetable oil (neem oil) by transesterification process with methanol, where potassium hydroxide (KOH) was used as a catalyst. Combustion chamber inner wall, Piston top surface (crown) and valve faces were coated with the Magnesium Zirconate (MgZrO3).

Energy conservation and efficiency have been the quest of engineers concerned with internal combustion engine. Approximately one-third of total fuel input energy is converted to useful work. Since the working gas in a practical engine cycle is not exhausted at ambient temperature, a major part of the energy is lost with the exhaust gases. In addition, another major part of energy input is rejected in the form of heat via the cooling system. Recently, much attention has been focused on achieving higher efficiency by reducing energy loss to coolant during the power stroke of the cycle. Thermal barrier coatings have a significant effect in the reduction of wear and abrasion failure in reciprocating and rotary engine for power generation and transportation. As operating temperature increases for improving Brake Thermal Efficiency, the wear and abrasion problem increases and becomes more challenging because lubrication in high temperature locations becomes increasingly problematic.

Energy conservation and efficiency have been the quest of engineers concerned with internal combustion engine. Theoretically, if the heat rejected could be reduced, then the thermal efficiency would be improved, at least up to the limit set by the second law of thermodynamics. Low Heat Rejection engines aim to do this by reducing the heat lost to the coolant. For current work a ceramic coated twin cylinder water-cooled diesel engine using blends of diesel and palm biodiesel as the fuel was evaluated for its performance and exhaust emissions. In recent years, Considerable efforts were made to develop and introduce alternative renewable fuel, to replace conventional petroleum-base fuels. Here, the diesel engine was insulated by Partially Stabilized Zirconia (PSZ) as ceramic material attaining an adiabatic condition. The cycle average gas temperature and metal surface temperature are higher in adiabatic engine.