斜抽运无机液体激光器的流场热分布  

The flow field heat distribution of inorganic liquid laser under oblique pumping

作　　者：胡滔[1] 魏泳涛[2] 宋影松[3] 张玉明[2] 李密[3] 马再如[1,4] 冯国英[1] 

机构地区：[1]四川大学电子信息学院,成都610064 [2]四川大学建筑与环境学院,成都610064 [3]中国工程物理研究院应用电子学研究所,绵阳621900 [4]西华大学物理与化学学院,成都610039

出　　处：《物理学报》2010年第10期7027-7035,共9页Acta Physica Sinica

基　　金：国家自然科学基金重大项目(批准号:60890203);国家自然科学基金(批准号:10976017);国家自然科学基金委员会与中国工程物理研究院联合基金(批准号:10676023)资助的课题~~

摘　　要：激光二极管斜抽运的多增益段串接的液体激光器能够明显地提高激光光束质量、获得较高的输出功率.针对斜抽运子增益段工作时所涉及的流动、传热和壁面耦合,建立了计算子增益段流场热分布的流-热-固耦合模型,应用有限单元法完成了其瞬态流场热分布的数值模拟.该方法排除了不精确的换热系数对计算结果的影响,使得换热系数不再是计算的先决条件,而只是计算结果之一;并且为评价流道形状、流速、吸收系数等因素对流场热的影响,以及进一步改进和控制液体激光介质的流场热分布,提供了可靠的分析方法.数值模拟研究表明:换热系数是空间位置的函数;流动传热效果随流速的增大而减小;激光介质流动时,温度分布与温度梯度分布具有相似性,与换热系数分布具有一定的互补性,且最大温度和温度梯度出现在下游流动介质的尖锐角落处。The multi-segment liquid laser system connected in series and obliquely pumped by LD can have significantly improved laser beam quality and higher output power.A flow-heat-solid interaction model for calculating the temperature distribution in the sub-gain section is established,which is focused on the flow,heat transfer and coupling in sub-gain section.We performed the numerical simulation of transient flow-field-heat distribution by way of the finite element method.The method proposed precludes the influence of the inaccurate film coefficient on the calculation results,the film coefficient is no longer a prerequisite,but a result of the calculation.Our method provides a new effective way to assess and control the flow-field-heat distribution which is affected by the flow channel shape,flow rate,absorption coefficient and other factors.Numerical results show that the film coefficient is a function of spatial location.Flow and heat transfer effieciency decreases with increasing velocity.When the laser medium is flowing,the temperature distribution and temperature gradient distribution are similar and are complementary to the film coefficient distribution,the maximum temperature and temperature gradient appears in the sharp corner downstream the flow.

关 键 词：液体激光器 流-热-固耦合模型 换热系数 流场热分布 

分 类 号：TN248.32[电子电信—物理电子学]