反应成型模具耦合温度场数值模拟与试验研究

Numerical Simulation and Experimental Research on Coupling Temperature Field of the Reaction Forming Mould

研究模具加热系统耦合温度场问题。根据模具加热系统的传热机理,将加热系统分为外部可控温度场和内部固化反应温度场。提出将模具内部反应固化温度场,作为外加可控温度场内载荷的耦合温度场建模方法,并进行数值模拟。以团絮状聚酯模塑料(Bulk molding compound,BMC)固化成型模具为研究对象,进行温度场试验;采用误差敏度分析法,对外加可控温度场进行热源强度误差敏度分析,计算出误差最大位置,以此来提高模具加热系统的制造精度,降低试验误差;通过改进加热工艺,实施三段式加热,结合多通道比例积分微分(Proportion-integration-differentiation,PID)控制器控制技术,按给定曲线拟合升温;数值模拟与试验结果吻合较好,模具型腔温度场的均匀性达到行业标准要求。

The coupled temperature field for mould heating system（MHS） is studied. According to the heat transfer mechanism of the MHS, it is divided into external controllable temperature field and internal curing reaction temperature field. Considering internal temperature fields of curing reaction as the load for controllable external temperature fields, a load definition method is proposed. Based on this method, the coupling temperature field of the mould heating system is established. Taking bulk molding compound （BMC） curing reaction mould as an example, the temperature experiment is carried out. Error sensitivity analysis method is used to analyze external controllable temperature field and calculate the maximum error position, as a result, the manufacturing accuracy of the MHS is improved, and experimental errors are decreased. To improve the temperature rise rate and make the mould cavity temperature field more quickly reach the thermal equilibrium, the curve of the heating process is decomposed into three periods. Using the multi-channel proportion-integration-differentiation（PID） control technology, the temperature is in strict accordance with curve. The simulation results agree well with the experimental results. The mould cavity temperature field met the industry standard.