复合薄膜热成型过程中热传导的数值分析

摘要

Aiming at the processes of heating and cooling in thermoforming, analyzed the transfer processes of composite film and established relevant mathematical model, then proposed a analytical calculation method of non-steady state temperature field of heat transfer of two-layers composite film. Calculated the solution of the differential equation by Laplace transform method, determined heat transfer parameter, then drew the curve of θ-t and θ-x by MATLAB. Put forward the general heat transfer function of two-layers composite film, applied it to design the time of heating and cooling and analyzed the temperature gradient, improved the thermoforming process and avoided the technological defects caused by heating and cooling.%针对复合薄膜在热成型加热和冷却中的传热问题,通过分析2层复合薄膜热传导过程的物理模型,建立相应的数学模型,提出了一种求解复合薄膜非稳态传热的解析方法.运用Laplace变换法求解导热微分方程理论解,确定薄膜的热传导参数后,利用MATLAB软件绘制θ-t及θ-x关系曲线.求解得2层复合薄膜的通用导热函数,并应用于热成型加热、冷却时间设计以及薄膜内部温度梯度分析,改善热成型工艺,从而避免因加热、冷却造成的工艺缺陷.