复合材料壳体固化过程温度场数值分析

Numerical study of temperature field evolution during composite case curing process

为解决固体发动机复合材料壳体固化成型过程中由于加热不均和固化不均导致的脱粘分层等质量缺陷问题,综合考虑了树脂的固化反应特性、固化炉内的热空气流动特性、复合材料物性参数的时变特性、模具和辅助材料的影响及其物性参数的时变特性,建立了壳体固化成型过程的热-化学耦合数学模型,数值模拟了固化过程中壳体温度的变化历程,获得了壳体固化过程中温度的变化规律。研究结果表明,模拟结果与测量结果的误差小于1.5%,表明所建立的模型能对壳体固化过程温度场进行较为准确的预估;壳体固化过程中没有出现放热峰,表明树脂的固化反应热对壳体固化过程影响微小;壳体固化过程中,最低温出现在临近接头区域。

In the curing process of the composite case,the non-uniform temperature field and the non-uniform curing degree field would lead to defects such as layer detachment. In this work,a thermal-chemical coupling model is established,in the model effects of resin curing reaction kinetics,hot air flow characteristics in the oven,composite and auxiliary material＇s physical parameters time-varying are considered. The temperature field evolution during curing process is studied numerically with the model.The results show that： the numerical prediction has a small error（ 1.5%） respect to experimental results,which indicates that the model can predict the distribution of temperature during the curing process accurately; The reaction heat nearly has no effect on the case curing process in this work,as no exothermic peak was observed; the minimum temperature points are at the pro-contact region of the metal rings at forward and aft domes.