Study on the effect of inclination angle on two-phase oscillating flow and heat transfer characteristics of piston cooling galleries

Abstract

The uneven temperature distribution of piston is one of the main reasons for piston fatigue failure. Piston cooling gallery is an effective cooling method to achieve an acceptable piston temperature field. However, the uneven temperature distribution of the piston surface due to the intake cooling effect is not considered in the traditional gallery design. In this paper, the effect of inclination angle on the flow and heat transfer characteristics of piston cooling galleries is investigated. To do so, the computational fluid dynamics (CFD) model for galleries with different inclination angle were established. These models were divided into groups A and B. The effect of inclination angle on the flow and heat transfer characteristics was numerically investigated. The results indicate that the OFR for group B is higher than that of group A. Compared with group A, more cooling oil in group B is accumulated near the oil outlet during the oscillation. The circumferential heat transfer performance is adjusted due to the oil accumulation effect. The average steady HTC decreases from 1138 W/(m2·K) to 974 W/(m2·K) while the inclination angle of galleries from −10° to 10°. These findings provide a new approach to balance piston temperature field.

Keywords

• Cooling gallery
• Inclination angle
• Two-phase oscillating flow
• Heat transfer