Modeling steam heat transfer in thermal protective clothing under hot steam exposure

Understanding heat and moisture transport in thermal protective clothing is essential to identifying how to protect the safety of workers subjected to steam leakage. This study develops a numerical model for simulating heat and moisture transfer in thermal protective fabric when exposed to hot steam. This model considers the impinging jet flow between steam nozzle and fabric, the non-transient equilibrium between three phases, the steam flow within the fabric induced by the pressure gradient, the dynamic moisture absorption, and possible phase changes during the process. Additionally, skin bio-heat transfer and Henriques burn integral models are incorporated into the steam heat transfer model to predict skin burn. Simulated fabric and skin temperatures from the model are validated with experimental results. The behavior of steam heat transfer and influencing factors on steam protective performance of fabric are analyzed. The results reveal that the pressurized steam can penetrate rapidly through the protective fabric and induce skin burn. The increase of fabric thickness insignificantly improves the steam protective performance, while the initial moisture content and the porosity of fabric both play an important role in improving the steam protective performance of clothing. (C) 2017 Elsevier Ltd. All rights reserved.