利用Polyflow软件计算了PVC自由发泡板材机头中增设分流板对机头内熔体流动特性的影响。结果表明,增设分流板能显著提高机头内熔体的压力,且分流板区域压力梯度的大小与出口平直定型段几乎相同,而对熔体出口速度均匀性的影响很小。这对解决出口平直定型段不能过长而机头压力又不能太低的矛盾提出了很好的解决方案。
The effect of the distributary part on the pressure distribution and flow characteristic in the fishtail free foaming die of PVC sheet was simulated with Polyflow software. The results showed that the distributary part improved the pressure of the melt obviously,and the pressure gradient in the distrybutory part segment was almost the same to that in the outlet fiat segment,but had little influence on the exit velocity uniformity of the melt. This can be used to obtain higher pressure with shorter outlet fiat segment in the die design.