NUMERICAL ANALYSIS OF CRYOGEN SPRAY COOLING OF SKIN IN DERMATOLOGIC LASER SURGERY USING REALISTIC BOUNDARY CONDITIONS
Laser dermatologic surgery is widely used for various skin problems. To prevent any unwanted damage of skins due to melanin absorption in the epidermis, cryogen spray cooling (CSC) is developed by spraying a cryogen on the surface prior to the laser implement. Several numerical analyses have been performed to investigate quantitatively the cooling effect of epidermis during CSC. Most of these studies have applied the Newton’s law of cooling on the cooling surface with a constant convective heat transfer coefficient () throughout the entire spray cooling process. Recent experimental works, however, demonstrate that the value of h may change significantly during CSC and is a strong function of both time and location. Based on the experimental measurements, this paper presents a generalized correlation for the normalized heat transfer coefficient as a function of the normalized time and space. The correlation is then introduced into a two-dimensional axisymmetric model of cryogen spray cooling in laser dermatological surgery of port wine stain. The model calculations demonstrated that the present correlation can correctly reflect the temporal and spatial characteristics of cryogen spray cooling and can be used for quantitative predictions of cryogen spray cooling of any laser dermatological processes.
cryogen spray cooling port wine stain laser dermatologic surgery convection heat transfer coefficient modeling.
Dong LI Yaling HE Yingwen LIU Guoxiang WANG
State Key Laboratory of Multiphase Flow, Xi’an JiaoTong University,Xi’an, 710049, China
国际会议
The 22nd International Congress of Refrigeration(第22届国际制冷大会)
北京
英文
2007-08-21（万方平台首次上网日期，不代表论文的发表时间）