Abstract:In this paper, experimental investigations are presented to assess the performance variations in a single cylinder spark ignited engine when run with three different gasoline-alcohol blends: (88% gasoline-12% methanol, 88% gasoline-12% ethanol and 88% gasoline-6% methanol-6% ethanol). Additional tests are carried out with the basic gasoline fuel for comparison analysis and performance assessment. Engine performance is investigated under a variety of engine operating conditions. The results are presented in the domain of engine speed. In particular, the brake power of the engine is shown to be slightly increased. The brake thermal efficiency showed an increase compared with the basic gasoline engine. Similarly, it is shown that brake specific fuel consumption is enhanced compared with basic gasoline engine. The exhaust gas temperature showed a decrease compared with gasoline fuel which is preferable to reduce emissions. The alcohol additives are strongly recommended to enhance performance, increasing the mileage and reducing the emissions.

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Transportation is a vital necessity without which the entire world would come to a standstill. The fossil fuels used to power transportation are consumed at rates of approximately 100,000 times their rate of natural formation, and their consumption subjects the human environment and ecosystem to significant damage. As substitutes for fossil-based diesel, second-generation biodiesels can eliminate many of the challenges concerning first-generation biodiesels in terms of their high cost and the food versus fuel debate. The seeds of the date palm tree have significant oil content and are a promising prospective energy source. This study investigated the potential environmental benefits of this biofuel in terms of diesel tailpipe emission reduction. The various blends of palm date biodiesel were produced and matched to fuel standard requirements, resulting in four standard-compatible blends that were tested in a diesel engine at varying operating conditions for speed and load. Although the biodiesel emissions had lower concentrations of CO2, CO, and HC relative to fossil diesel, higher concentrations of NOx were detected. The results suggest that date-seed biodiesel could become a sustainable energy source for the transport sector, although further technical and economic investigations will be required before its wide deployment.

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Electronic cooling plays a role in removing the electronic equipment’s heat rate to prevent failure from occurring. Electronic cooling performance is based on many parameters, such as thermal characteristics and material type design. Pure aluminium, copper – aluminium, and aluminium - beryllium are selected for predicting the performance of a heat sink. It was observed that the presence of Aluminium-copper alloy raises the performance of the heat sink compared with that of the pure aluminium. In contrast, the heat sink performance using aluminium - beryllium alloy was less than that of the reference material (pure aluminium). It was found that the heat dissipated from the heat sink increases by 1.4 % with using aluminium-copper alloy instead of using pure aluminium while the heat dissipated drops by 2% with using aluminium - beryllium alloy compared with that of using pure aluminium. Further, the heat sink mass decreases with the use of the aluminium-beryllium and increases with using copper - aluminium instead of pure aluminium. Whereas the mass of the heat sink using aluminium-copper alloy is higher than that of the pure aluminium by 2.3% while the mass of the heat sink using aluminium - beryllium alloy is less than that of the pure aluminium by 2.4%.

While a number of liquids are preferred in many heating and cooling applications, their thermal capacity can be a limiting factor in many thermal systems. Therefore, a series of methods such as use of mixtures of two or more fluids, emulsions, phase change materials, and more recently nanoparticle enriched fluids have been proposed. The impact of adding aluminum and copper nanoparticles to water in a closed-loop radiator has been investigated analytically and numerically. Heat transfer performances of different working fluids are studied under the same boundary conditions. The analytical and numerical models including external and internal flow domains of the radiator have been developed, and free convection air cooling has been considered over external surfaces of a radiator. Both plain and nanoparticle added fluid cases are analyzed individually to differentiate the impact over heat transfer. The results indicate that the presence of nanoparticles effectively raised the convective heat transfer coefficient and thus the performance of the radiator system increased by 2.1% and 0.6%, respectively, in comparison to plain water operating condition. Furthermore, the radiator tube length has been shortened by 2.0% and 0.75% for both Al and Cu nanoparticle filled fluid, respectively, to obtain the same thermal performance at a single tube. The total required heat transfer surface area is also reduced by 2.0% and 1.15% for Al and Cu, respectively. Finally, a comparison between analytical and numerical models has been found to be in a good agreement of heat transfer coefficient and Nusselt number.