硅质微通道玻璃化保存芯片的结构热应力分析  

Thermal Stress Analysis of a Silicon Microchannel Chip for Vitrification Preservation

作　　者：王洋 于亚婷[1] 王吉 陈春 WANG Yang;YU Ya-ting;WANG Ji;CHEN Chun(School of Mechanical,Electronic,and Industrial Engineering,University of Electronic Science and Technology of China,Sichuan Chengdu 611731,China)

机构地区：[1]电子科技大学机械电子工程学院,四川成都611731

出　　处：《机械设计与制造》2018年第A02期141-144,共4页Machinery Design & Manufacture

基　　金：国家自然科学基金(批准号:51206019"基于微流控的生物材料片上低温保存方法研究"&批准号:51676030"面向玻璃化保存的微尺度传热机理和强化方法研究")

摘　　要：玻璃化保存是指以超高速降温促使生物材料发生玻璃化转变后低温存贮,能有效避免传统低温保存过程中冰晶生长等因素造成的低温损伤,是细胞、组织等生物材料的理想长期保存方法。基于微通道换热原理的玻璃化保存芯片技术能够满足玻璃化保存的超高速降温需求,但降温过程中的快速温度变化将产生较大的热应力,对芯片结构可靠性产生重要影响。特别当芯片采用硅这种生物相容性好但强度较差的材料时,热应力影响更为突出。建立微通道玻璃化保存芯片的三维CFD模型,对降温过程中的流动沸腾换热过程和热应力作用进行整场求解,预测不同条件下芯片降温性能及结构中的应力场,并采用正交试验方法设计算例,分析微通道深度、宽度、壁厚和长度等结构参数对芯片内热应力的影响规律。结果表明,各参数对硅质微通道芯片结构热应力的影响程度从大到小依次为:通道深度,通道壁厚,通道宽度,通道长度;通过正交试验所得出的最优参数组合能在满足玻璃化保存所需降温速率的同时保证芯片的结构强度。所提出的仿真方法和结果将为微通道玻璃化保存芯片技术的进一步发展和应用提供重要支持。As a new cryopreservation method,vitrification is ideal for long-term preservation of biological materials,such as cells and tissues.Microchannel-chip technique has been proposed to produce the ultra-high cooling rate required for vitrification of biomaterials,but the rapid changes in structural temperature during the cooling process may greatly increase the thermal stress in the microchannel chips.Silicon has good biocompatibility but poor strength of material.When the chip is made of silicon,thermal stress have a significant impact to the reliability of the chip structure.In this paper,we establish a three-dimensional CFD model to simulate the fluid-solid coupling heat transfer in the cooling process.The transient temperature and stress fields of the silicon microchannels are obtained.An orthogonal test method is used for the analysis of the effects of structural parameters,such as depth,width,wall thickness,and length,on thermal stress in the microstructures.Results show that the channel depth has the highest influence on thermal stress in the chip structure,followed by channel wall thickness,channel width,and channel length.Furthermore,retention of the structural strength of chips and the cooling rate of vitrification can be both achieved by optimizing the combination among the parameters through orthogonal experiments.The simulate approach as well as the results obtained herein will provide important support for the further development and application of microchannel-chip technique.

关 键 词：玻璃化保存 硅微通道 热应力 正交试验 

分 类 号：TH16[机械工程—机械制造及自动化] TK123[动力工程及工程热物理—工程热物理]