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A one-dimensional numerical calculation has been performed on a new reciprocating heat engine proposed on the basis of super-adiabatic combustion in porous media. The system consists of two pistons and a thin porous medium in a cylinder; one being a displacer piston and the other a power piston. These create reciprocating motions with a phase relation angle. By means of the reciprocating flow system, the residual combustion gas enthalpy is effectively regenerated to induce enthalpy increase in the mixture through the porous medium. Due to heat recirculation, the thermal efficiency reaches to 58% under the condition of the compression ratio of 2.3.

The present study aims to investigate the parameters affecting cold start characteristics of ethanol at low temperature, and suggest a solution to avoid cold starting problem without the installation of second fuel tank. The testing engine is a 125cc volume displacement, single-cylinder four strokes SI engine with fuel injection and ignition timing system controlled by ECU (electronic control unit). The cold starting performance tests were extensively conducted with different percentages of ethanol blends, surrounding temperatures, heating inside combustion chamber, heater injector, pre-cranking without fuel injection, and amount of fuel injection. From the experimental results, when using ethanol fuel in conventional engine, the problem of cold starting was observed at surrounding temperature lower than 20°C for ethanol. Increasing of injection duration can lower the possible cold start temperature of neat ethanol.

Soot particles are produced inside the combustion chamber of the internal combustion engines and will later be exhausted into the thermosphere. Part of these particles will contaminate the engine oil. When this happens, diesel engine abrasion or, in a worst-case scenario, lubricant starvation will occur. This circumstance will eventually cause engine wear. This research uses X-Ray Fluorescence (XRF) technique to analyze the additive element in engine oil. For wear test, this research uses tribology Four ball wear tester to substitute point contact wear mechanism. Then the worn surface is analyzed with Scanning Electron Microscope (SEM). Confocal Microscope are used to study the effect of additive on soot dispersion in engine oil, which affects the metal wear mechanism. This research use Laser Particle Size Analyzer to investigate performance of soot dispersant additive in each engine oil.