本文選題：微通道熱沉　切入點(diǎn)：散熱性能　出處：《北京工業(yè)大學(xué)》2015年碩士論文

【摘要】：半導(dǎo)體激光器因其轉(zhuǎn)換效率高、壽命長、體積小、重量輕、可靠性高、能直接調(diào)制且易與其他半導(dǎo)體器件集成等優(yōu)點(diǎn),廣泛應(yīng)用于工業(yè)加工、激光醫(yī)療、激光通訊、信息顯示,航空航天等領(lǐng)域。高的光輸出功率帶來的高耗散熱量如不及時(shí)消除會(huì)造成溫升導(dǎo)致閾值電流升高,效率降低,激光波長發(fā)生溫漂等影響光束質(zhì)量。芯片溫度的控制是半導(dǎo)體激光器發(fā)展中的一個(gè)重要的研究領(lǐng)域,微通道熱沉作為半導(dǎo)體激光器主要的散熱方式已成為其高性能工作的關(guān)鍵器件。依據(jù)計(jì)算流體力學(xué)和計(jì)算傳熱學(xué)理論,從實(shí)驗(yàn)影響物理量出發(fā)選擇并確定控制方程,使用有限體積法對控制方程離散,基于一款微通道熱沉確立物理和數(shù)學(xué)模型,對導(dǎo)入模型加載邊界條件和初始參數(shù),用可實(shí)現(xiàn)k-?模型作為湍流計(jì)算模型。利用FLUENT軟件進(jìn)行了微通道熱沉內(nèi)部通道流場溫度場的數(shù)值計(jì)算和后處理。影響微通道熱沉散熱性能的主要結(jié)構(gòu)因素是:進(jìn)出口寬度、微通道寬度、間距、高度及通道脊長度。通過數(shù)值模擬分別研究了進(jìn)水通道流量不均勻的原因;在微通道高度進(jìn)出口寬度為固定值的條件下微通道寬度,間距,通道脊長度和壁面粗糙度4個(gè)因素分別對芯片表面溫升和壓降散熱性能的影響規(guī)律兩個(gè)方面。提出改進(jìn)方案優(yōu)化進(jìn)水層通道結(jié)構(gòu)使返水孔流量均勻化;表面溫升隨微通道間距、寬度、通道脊長度變小而降低但趨勢放緩,壓降隨間距減小寬度增加而減小,隨長度增加而增大;一定范圍內(nèi),溫升隨壁面粗糙度增大而減小,壓降隨之增大而增大。數(shù)值計(jì)算獲得特定外形尺寸下最優(yōu)內(nèi)通道結(jié)構(gòu)尺寸參數(shù),理論上驗(yàn)證了SLM工藝表面質(zhì)量對熱沉散熱性能提升可行性。最優(yōu)結(jié)構(gòu)熱沉熱阻為0.34K/W,壓降為0.9bar。利用EOS M270成型設(shè)備從工藝參數(shù)對成型件致密度和表面粗糙度的影響規(guī)律;純鎳微小結(jié)構(gòu)成型質(zhì)量;熱沉擺放方式和支撐添加方法3個(gè)方面來研究采用SLM制造純鎳微通道熱沉的工藝。得到成型質(zhì)量最優(yōu)的工藝參數(shù)、成型尺寸范圍及成型擺放和支撐添加方法,并制造出經(jīng)數(shù)值計(jì)算優(yōu)化的微通道熱沉。將成型的微通道熱沉表面處理后與單bar輸出功率80W的半導(dǎo)體芯片封裝進(jìn)行功率光譜等激光參數(shù)測試,經(jīng)測量得在流量0.3L/min下芯片表面溫升18℃,計(jì)算得此微通道熱沉熱阻0.39K/W,壓降1.4bar,滿足芯片散熱要求,驗(yàn)證了優(yōu)化方案的可行性。
[Abstract]:Semiconductor lasers are widely used in industrial processing, laser medical treatment, laser communication and information display because of their advantages such as high conversion efficiency, long life, small volume, light weight, high reliability, direct modulation and easy integration with other semiconductor devices.Aerospace and other fieldsIf the high heat dissipation caused by high optical output power is not eliminated in time, the threshold current will increase, the efficiency will decrease, and the laser wavelength temperature drift will affect the beam quality.The control of chip temperature is an important research field in the development of semiconductor lasers. As the main heat dissipation mode of semiconductor lasers, microchannel heat sink has become the key component of its high performance work.According to the theory of computational fluid dynamics and computational heat transfer, the governing equations are selected and determined from the experimental effects of physical quantities. The control equations are discretized by the finite volume method, and the physical and mathematical models are established based on a microchannel heat sink.For the import model to load boundary conditions and initial parameters, using the implementable k-?The model is used as turbulence calculation model.The numerical calculation and post-processing of the flow field temperature field in the microchannel heat sink are carried out by using FLUENT software.The main structural factors affecting the heat sink performance of microchannel are the width of inlet and outlet, the width of microchannel, the spacing, the height and the length of channel ridge.Through numerical simulation, the causes of the inhomogeneous flow in the inlet channel are studied respectively, and the width and spacing of the microchannel under the condition of fixed inlet and outlet width of the microchannel height are studied.The influence of channel ridge length and wall roughness on the performance of temperature rise and pressure drop on the chip surface is discussed in this paper.An improved scheme is proposed to optimize the structure of the influent layer channel so as to homogenize the flow rate of the backwater hole, and the surface temperature rise decreases with the distance between the microchannels, the width and the length of the channel ridge, but the trend slows down, and the pressure drop decreases with the decrease of the spacing width.The temperature rise decreases with the increase of the wall roughness and the pressure drop increases with the increase of the length.The optimal structural parameters of the inner channel are obtained by numerical calculation. It is proved theoretically that the surface quality of SLM process can improve the heat sink performance.The heat sink resistance of the optimal structure is 0.34 K / W and the pressure drop is 0.9bar.The effect of process parameters on density and surface roughness of molded parts was studied by using EOS M270 forming equipment.In this paper, the heat sink process of pure nickel microchannel made by SLM was studied in three aspects: heat sink arrangement and support addition method.The optimum process parameters, forming dimension range, forming arrangement and support adding method were obtained, and the heat sink of microchannel was fabricated by numerical calculation.The fabricated microchannel heat sink surface was treated with a semiconductor chip with a single bar output power of 80W. The laser parameters such as power spectrum were measured, and the temperature rise of the chip surface was measured at 18 鈩，

本文編號：1712220