Coding System Design of Four-cylinder Engine and Engine Temperature Analysis.

To evaluate the rationality of the cooling system design for a four cylinder engine, computational fluid dynamics method was used to analyze the engine cooling system from layout design, system flowrate determination, flow field of the cooling system and engine temperature field. The optimization design of adding a throttling notch to the cylinder block water jacket was proposed to solve the problem of significant differences in coolant flow velocity in the cylinder block water jacket. The results show that the coolant flow velocity uniformity in cylinder block water jacket is significantly improved, and the wall temperature of each cylinder liner can be reduced by 1~3 °C. The thermal balance test results at an engine speed of 12 000 r/min show that the maximum difference in cylinder temperature is about 4 °C. The oil temperature is about 129 °C, which is controllable (less than 140 °C), indicating that the cooling system of the four cylinder engine is designed reasonably to ensure uniform cooling of each cylinder and oil cooling. [ABSTRACT FROM AUTHOR]