Heat-transfer dynamics during cryogen spray cooling of substrate at different initial temperatures
Heat-transfer dynamics during cryogen spray cooling of substrate at different initial temperatures
复制标题
DOI：
10.1088/0031-9155/49/23/007
复制
发表时间：
2004-12-07
影响因子：
3.5
通讯作者：
Nelson, JS
中科院分区：
文献类型：
--
作者：
Jia, WC;Aguilar, G;Nelson, JS
低温喷雾冷却（CSC）用于在皮肤病治疗过程中最大限度地减少表皮损伤。然而，在瞬态冷却过程中的热传递的主导机制是不完全理解。本研究的目的是通过测量初始衬底温度（T-0）对冷却动力学的影响来阐明CSC的物理机制。通过直管喷嘴将冷冻剂输送到皮肤体模上。使用快速响应热电偶记录之前的体模温度变化。在冷冻剂喷射期间和之后。表面热通量（q”）和传热系数（h）使用逆热传导算法计算。观察到最大表面热通量（q”（max））随着T-0而增加。q”对应的表面温度也随T-0的增加而增加，但后者对h的影响不显著。可以得出结论，即使T-0为80 degreesC，冷冻剂喷雾和皮肤体模之间的热传递仍保持在核沸腾区域。
Cryogen spray cooling (CSC) is used to minimize the fisk of epidermal damage during dermatologic therapy. However, the dominant mechanisms of heat transfer during the transient cooling process are incompletely understood. The objective of this study is to elucidate the physics of CSC by measuring the effect of initial substrate temperature (T-0) on cooling dynamics. Cryogen was delivered by a straight-tube nozzle onto a skin phantom. A fast-response thermocouple was used to record the phantom temperature changes before. during and after the cryogen spray. Surface heat fluxes (q") and heat-transfer coefficients (h) were computed using an inverse heat conduction algorithm. The maximum surface heat flux (q"(max)) was observed to increase with T-0. The surface temperature corresponding to q" also increased with T-0 but the latter has no significant effect on h. It is concluded that heat transfer between the cryogen spray and skin phantom remains in the nucleate boiling region even if T-0 is 80 degreesC.