Abstract:

In view of a large temperature difference in the temperature distribution of the melting chamber， the heat transfer in the melting chamber of a hot?air melting waste plastic granulator was simulated by using the Fluent simulation software. By comparing the temperature distribution of the melting chamber with different inlet diameters， different inlet positions， and different inlet wind speed， the effects of inlet diameter， inlet position， and inlet wind speed on the temperature distribution of the melting chamber were investigated. An orthogonal experiment was performed to explore the optimal parameter components and distinguish the primary and secondary factors. The analysis results indicated that the temperature inside the melting chamber increased significantly with an increase in the diameter of the air inlet increases when using the controlled variable method. However， this temperature varied with a variation of the position of the air inlet. If the distance between the air inlet and the main shaft was too small or too large， the temperature distribution of the melting chamber was inhomogeneous. Only in the middle area， the temperature distribution of the melting chamber was more uniform， and there was no obvious change with an increase in the air inlet speed. Through the orthogonal experiment， the optimal parameter group was determined to be an air?inlet diameter of 120 mm， a distance of 47.7 ℃ between the air inlet and center 150 mm， and a wind speed of 2 m/s at the air inlet. It is concluded that the optimized scheme with an air?inlet diameter of 120 mm and an air inlet distance of 150 mm from the center should be adopted to avoid a large temperature difference in the melting chamber.

Key words: waste plastic, melting chamber, Fluent, controlled variable method, temperature field, orthogonal test