基于微通道热沉的片状激光放大器散热模拟及优化  

Simulation and Optimization of Heat Dissipation in Slab Laser Amplifier Based on Microchannel Heat Sink

作　　者：王浩然 王建磊 李培丽[1] 卢振旭[1] 马福晓 马云杰 周军 陈卫标 Wang Haoran;Wang Jianlei;Li Peili;Lu Zhenxu;Ma Fuxiao;Ma Yunjie;Zhou Jun;Chen Weibiao(College of Electronic and Optical Engineering&College of Flexible Electronics(Future Technology),Nanjing University of Posts and Telecommunications,Nanjing 210023,Jiangsu,China;Nanjing Institute of Advanced Laser Technology,Nanjing 210038,Jiangsu,China;Shanghai Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Shanghai 201800,China)

机构地区：[1]南京邮电大学电子与光学工程学院、柔性电子(未来技术)学院,江苏南京210023 [2]南京先进激光技术研究院,江苏南京210038 [3]中国科学院上海光学精密机械研究所,上海201800

出　　处：《中国激光》2023年第7期144-152,共9页Chinese Journal of Lasers

基　　金：国家自然科学基金(61275067);中国科学院重点部署项目(ZDRW-KT-2019-3-3);科工局民用航天技术预先研究项目(D010105)。

摘　　要：为实现片状结构高重复频率大能量激光放大器的高效热管理,采用有限元分析(FEA)方法,充分考虑增益介质内部非均匀热分布、微通道热沉中的流速、对流扩散等影响因素,引入流-热-固多物理场耦合数值分析模型,对激光放大器热沉进行分析优化,并基于优化结果探讨了不同流速下微通道热沉的散热冷却能力。模拟结果表明:当基底厚度H_(b)=2 mm、单个微通道高度H_(c)=4 mm和宽度W_(c)=0.4 mm、两微通道的间距W_(w)=0.3 mm时,微通道热沉冷却能力最强,热阻最小;微通道内冷却液流速过大会导致较大的流动压力损失;微通道热沉的平均等效换热系数可达50000 W/(m~2·K)。Objective Diode-pumped solid-state lasers(DPSSLs)are widely used in many applications owing to their high energy,high repetition rate,and high efficiency.The gain medium is one of the core components of the DPSSL system;however,when the gain medium is subjected to a high-power pumping source,an uneven heat source is formed in it,resulting in an uneven temperature distribution.Furthermore,the cooling device can only dissipate heat to its surface,which in turn generates temperature gradients in different directions.The thermal deformation and stress caused by the temperature gradient in the gain medium eventually degrade the laser output power and beam quality.In this study,the finite element analysis(FEA)is used to optimize the design of a microchannel heat sink for laser amplifier cooling,and the effects of parameters such as microchannel bottom-plate thickness,channel height,channel width,channel wall thickness,and inlet velocity on the maximum temperature of the gain medium surface are investigated.The results are expected to provide accurate guidance for practical experiments.Methods To study the ability of the microchannel heat sink to cool the laser amplifier,a full-size model containing a slab-type gain medium and a microchannel heat sink is established(Fig.1).The uppermost layer is the gain medium,the middle layer is the microchannel heat sink,and the bottom layer is the cover plate.The flow and convection-diffusion phenomena occurring in the inhomogeneous heat and microchannel heat sink within the slab-type gain medium are then studied by a flow-heat-solid multiphysical field coupling analysis.Finally,the coupling of heat and fluid under full-size model conditions is directly simulated using the ANSYS FLUENT module,in which the heat source within the gain medium is loaded through the UDF command.The pressure-velocity coupling is achieved using the SIMPLE algorithm,the flow parameter interpolation method is second-order windward,the heat sink material is purple copper,and the cooling medium is deionized wa

关 键 词：激光器 微通道 片状激光放大器 非均匀温度分布 流-热-固耦合模型 数值仿真 

分 类 号：TN248.1[电子电信—物理电子学]