(1.School of Mechanical Engineering,Hebei University of Technology,Tianjin300400,China;2.Tianjin Key Laboratory of Power Transmission and Safety Technology for New Energy Vehicles,Tianjin300400,China;3.Product R&D Institute,Jiangling Motors Co.,Ltd.,Nanchang330001,China)
In order to study the oscillating flow and heat transfer effect of lube oil in the cooling oil gallery of piston double jet inlet during the reciprocating motion of piston, the distribution of cooling oil and the wall heat transfer for the cooling gallery under the transient motion conditions were investigated based on the dynamic mesh of CFD software, and compared with those for the single-jet inlet oil cooling galleryunder the same boundaries. According to the analysis, the double jet inlet oil cooling gallery had the better effect, the oil filling rate and the average heat transfer coefficient increased by 11.5% and 13.3% respectively, and the oil and wall heat transfer coefficient were more even in the circumferential direction of oil cooling gallery. Finally, the results of oscillation cooling calculation were mapped to the piston temperature field boundary, and the piston temperature field with two kinds of oil cooling gallery was analyzed. The results show that the temperature at the top of piston with the double jet inlet oil cooling gallery is lower in general , the maximum temperature decreases by 7 ℃, and the temperature at the auxiliary thrust side of top surface decreases significantly.
