Effect of position of inner cooling gallery on piston temperature field of diesel engine
                                                               ZONG Ming jing, DONG Fei, ZHU Nan lin
                                  （School of Automotive and Traffic Engineering, Jiangsu University, Zhenjiang 212013, China）

Abstract: Aiming at the problem of high temperature of piston, a turbocharged diesel engine piston was taken as the research object. Combined with the results of piston temperature field test and on the basis of piston temperature field calculation model was verified, the structure of inner cooling gallery was designed in piston. Then the cooling effect of piston was obtained. By the axial and radial movement of piston inner cooling gallery, the effect of different position of inner cooling gallery on piston temperature field was studied. The temperature and heat transfer coefficient of the inner cooling gallery were simulated by CFD software. The results indicate that with the added structure of inner cooling gallery, the supreme temperature can be reduced nearly 40 ℃. When the inner cooling gallery of piston moves axially 4 mm, the temperature of piston top can be reduced about 10 ℃. The results provide a reference for the structure design of the inner cooling gallery.

Key words: piston; inner cooling gallery; temperature field; cooling effect