Based on the gas-side local heat transfer boundary conditions of cylinder head and cylinder liner obtained by the in-cylinder heat transfer model and the water-side heat transfer boundary conditions obtained by the homogeneous flow boiling heat transfer model

a heat transfer calculation of the structural temperature field coupled with the gas side and water side boundary conditions was carried out on an in line 6 cylinder diesel engine for commerical vehicles

and the state of boiling heat transfer in cylinder head water channel was evaluated. Results show that the simulation results of the cylinder head temperature are in good agreement with the measured values. The maximum cylinder head temperature is located at the bridge zone between two exhaust valves on the cylinder head fire deck. The gas heat transfer coefficient and gas temperature between the exhaust valves are at a high value

while the in cylinder local heat transfer is significant. The cooling water at the center of the cylinder head fire deck and in the water channel near the exhaust valve is in a state of partially developed nucleate boiling.