注射过程喷嘴内物料温度和压力的模拟与分析

利用Fluent软件对注射过程中物料在喷嘴内的流动进行了模拟，分析了喷嘴内剪切热产生的位置及喷嘴尺寸与物料温度变化和压力降的关系。结果表明，注射过程中喷嘴内最高温升位置出现在壁面附近的很小区域内，温升变化率随喷嘴圆管直径的增加而降低，随喷嘴圆管长度的增加而提高；喷嘴出口处物料温度随喷嘴圆管直径增加逐渐趋向均匀；注射过程中喷嘴内压力降随喷嘴圆管直径减少和长度的增加而提高。

SIMULATION AND ANALYSES OF MELT TEMPERATURE AND PRESSURE IN NOZZLE DURING INJECTION MOLDING

The melt flow inside the nozzle during injection molding is simulated by using Fluent software. The position at which shear heat generates and the relationship between nozzle size and variety of melt temperature or pressure drop are analyzed. As a result, the position at which the temperature rises furthest appears within the small region closely to the nozzle wall. Variety rate of temperature rise diminishes gradually with the augment of nozzle diameter and rises little by little with the augment of nozzle length. Melt temperature at the exit tends to equality gradually when the nozzle diameter augments, and the pressure drop increases along with the diminish of nozzle diameter and the augment of nozzle length.