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Temperature measurement experiments with intake port model were done to achieve the fundamental information on constructing physical model that expresses the heat transfer phenomena in the intake manifold and intake port. The experiments were done with steady airflow, and the size, shape, heating condition of the port model and mass flow rate were changed as experimental parameters. As the results, it was clear that the developing condition of velocity and thermal boundary layer had greater influence than the shape factor, and the coefficient and the exponent of the equation derived from the relationship between Nusselt number and Reynolds number had great difference from those of generally used Colburn's equation in undeveloped entrance region, but they got closer as developing boundary layer.

The electronic controlled carburetor and ignition system has been developed. In accordance with various working conditions of the engine, the system adjusted corresponding control parameters; air fuel ratio and ignition timing, therefore it could keep the engine working on the optimal conditions. Through analyzing overall performance of the engine based on the experimental data, we had concluded that the specific fuel consumption was improved about 8-10%, and the exhaust emission performance was improved correspondingly after electronic control, the improved ratio was about 10% for HC emission and 97% for CO emission.

This investigation was concerned with the rate of heat transfer from the working gases to the combustion chamber walls of the internal combustion engines. The numerical formula for estimating the heat transfer to the combustion chamber wall was derived from the theoretical analysis and the experiment, which were used the constant volume combustion chamber and the actual gasoline engine. As a result, mean heat transfer in the internal combustion engine becomes possible to estimate with measuring the cylinder pressure. In addition, the derived numerical formula forms with quite simple variables. Therefore it is very useful for engine design.