Abstract: Die is one of the key devices in of polypropylene pelletizing. The temperature filed of the die has an important influence on the quality of pelletizing granules. A three-dimensional model of heat transfer for a die of pelletizing under water is established and solved by numerical simulation to obtain distribution of temperature inside the die. The numerical results show that temperature distribution of profile in different thickness due to heating of heat-conducting oil. Cooling of die results in pelletizing surface with lower temperature. Combined action of heating of heat-conducting oil and cooling of water leads to greater gradient of temperature close to the pelletizing surface. Numerical simulation and analysis of temperature field of pelletizing die can provide good theorical support for design and optimization of heat-conducting oil pipeline and die hole inside the die.

Key words: Die, Numerical simulation, Polypropylene, Temperature field