A coating die forms liquid layers of uniform thickness for application to a substrate. In a dual-cavity coating die an outer cavity and slot improves flow distribution from an inner cavity and slot. A model for axial flow in the outer cavity must consider the ever-present cross flow. A 1-D equation for the pressure gradient for a power-law liquid is obtained as a small departure from a uniform flow distribution and no axial flow. The equation contains a shape factor dependent on cavity shape, Reynolds number, and power-law index. The shape factor for five triangular cavity shapes is obtained by finite-element analysis and correlated for application to die design up to the onset of flow recirculation which arises at the junction of the cavity and outer slot. The performance of the combined cavity and slot is considered and the most effective design determined. © 2017 American Institute of Chemical Engineers AIChE J, 2017

中文翻译：

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通过二维有限元分析确定参数的双腔模具外腔模型

涂覆模具形成均匀厚度的液体层，以施加到基底上。在双腔涂层模具中，外腔和缝隙改善了来自内腔和缝隙的流动分布。外腔中轴向流动的模型必须考虑一直存在的横向流动。对于幂律液体的压力梯度的一维方程式与均匀的流量分布相距很小，并且没有轴向流量，因此得到了。该方程式包含取决于腔体形状，雷诺数和幂律指数的形状因子。通过有限元分析获得了五个三角形腔体形状的形状因数，并将其与模具设计相关，直到在腔体与外槽的交界处出现的流动再循环开始为止。考虑了组合式腔和槽的性能，并确定了最有效的设计。©2017美国化学工程师学会AIChE的Ĵ，2017年