Analysis of Cylinder Bore Distortion During Engine Operation

A calculation method of the bore distortion during engine operation was developed. This method can consider the sliding effect of the cylinder head on the top dock of the cylinder block. The bore distortion during engine operation calculated by this method agrees with that measured by Fujimoto, better than that calculated by conventional method. Calculated results for a Toyota 4-cylinder in-line 1.5L engine showed that thermal distortion has larger effects on the cylinder bore distortion during engine operation than cylinder head clamping distortion.