This study experimentally and numerically investigates a typical HDPE blown film production process cooled via a single-lip air-ring. The processing observations are considered for the proposed subsequent modifications on the air-ring design and the location relative to the die to generate a radial jet, directly impinging on the bubble. Measurements are performed to collect the actual operating parameters to set up the numerical simulations. The radiation heat transfer and the polymer phase change are considered in the numerical simulations. The velocity profile at the air-ring upper-lip is measured via a five-hole Pitot tube to compare with the numerical results. The comparison between the measurements and the numerical results showed that the simulations with the STD $k–\omega$ turbulence model are more accurate with a minimum relative absolute error (RAE) of 1.6%. The numerical results indicate that the peak Heat Transfer Coefficient (HTC) at the impingement point for the modified design with radial jet and longer upper-lip is 29.1% higher than the original design at the same conditions. Besides, increasing the air-ring upper-lip height increased the averaged HTC, which is 13.4% higher than the original design.

本研究通过实验和数值研究了一个典型的 HDPE 吹膜生产工艺，该工艺通过单唇空气环冷却。加工观察被考虑用于对空气环设计和相对于模具的位置的提议的后续修改，以产生直接撞击气泡的径向射流。执行测量以收集实际操作参数以建立数值模拟。在数值模拟中考虑了辐射传热和聚合物相变。通过五孔皮托管测量空气环上唇处的速度分布，以与数值结果进行比较。测量值和数值结果之间的比较表明，STD 的模拟$克\mathrm{——}\omega$湍流模型更准确，最小相对绝对误差(RAE)为 1.6%。数值结果表明，在相同条件下，具有径向射流和更长上唇的改进设计在撞击点处的峰值传热系数（HTC）比原始设计高29.1％。此外，增加气环上唇高度也增加了平均HTC，比原设计高出13.4%。