Structural optimization on heat transfer characteristics in polyurethane foam film melting process by deflagration method

Flexible polyurethane foam (FPUF) is extensively utilized in various industrial sectors, due to its distinctive porosity. The deflagration approach is a prevalent method employed to reticulate polyurethane foam. The open porosity of the polymer, along with its reticular framework, significantly shape the structure of FPUF and consequently impact its mechanical properties. This study investigates the impacts of two pivotal parameters, pore size and film thickness, on the open porosity of the foam film. The heat transfer characteristics are studied by standard k-ε model coupling with the melting-solidification model based on the enthalpy-porosity method analysis model, and nine PUF models are selected as the evaluation objects. The experimental results indicate that the reticulation effect is more favorable when the open porosity ranges from 0.7 to 0.85. Based on these findings, the parameters with large variation degrees have a greater influence on the melting process of FPUF film. Furthermore, FPUF composites characterized by thicker films and smaller pores demonstrate a remarkable reticulation performance. The insights garnered from this study hold promise for advancing the comprehension of the underlying mechanisms governing FPUF deflagration, thereby facilitating the optimization of its structural applications in industrial domains.