本文采用有限容积法对制冷剂喷射冷却(Cryogen spray cooling,CSC)过程进行了数值分析,研究了皮肤组织温度场随时间、空间的分布规律,初步分析了喷射过程中可能发生的冷损伤,探讨了不同喷嘴距离对于喷射换热过程的影响。结果表明:本文的模拟结果定性符合文献中的试验结果;由于制冷剂喷射不均匀性带来的冷保护不足问题可以通过适当延长冷却时间(如大干80ms)加以避免;低温制冷剂带来的冷损伤仅局限于浅表皮层,不会对人体造成伤害;喷射距离对于整个换热过程的影响非常有限,可以较为自由地布置喷嘴位置。
A quantitative analysis of the cryogen spray cooling process was performed here by numerical method. The codes were used to simulate the dynamic variation and spatial distribution of the surface temperature. The potential cold injury and the effect of the spray distance were analyzed. Through the simulation results, it's clear that our results were in accordance with the experimental results in references; the non-uniform spatial temperature distribution which may attribute to the non- uniform spray could be eliminated by prolonging the spray duration (such as longer than 80 ms); the potential cold injury which may caused by the low temperature cryogen was limited in the epidermal layer, and its influence on human health was tiny; the effect of the spray distance on the heat transfer process was not obvious, so the placement of the nozzle could be flexible in clinical practice.