Effects of PCM cooling vest design parameters on garments’ regional performance under low-level radiant heat exposure

There is no consensus regarding the optimal design parameters of PCM cooling garments for reducing heat strain under low-level radiant heat exposure, nor on their differentiated configuration strategies for different body regions. This highlights the urgent need for a systematic investigation of the factors affecting clothing performance. In this study, the effects of radiant intensity, PCM packet gap, and phase change temperature on the heat transmission and thermal protection performance of different torso regions under uniform thermal radiant intensity were explored. The investigation was conducted using the thermal manikin ANDI, employing an experimental strategy that combined single-factor analysis with orthogonal optimization. The results indicate that the effects of these three factors on the performance of each vest region are relatively independent of one another. Among these factors, radiant intensity has the most significant impact. Based on the human body’s physiological characteristics, it is preferable to use a smaller PCM packet gap in the chest and lower back compared to other regions, and a higher phase change temperature in the chest to prolong cooling time. The acceptable wearability of the PCM cooling vest was further confirmed by wearing trials. These findings can provide methodological support for establishing performance evaluation standards for PCM cooling garments and the development of high-performance personal thermal protection equipment.