涡旋微槽流动与传热特性数值模拟

涡旋微槽散热器具有传输高热流密度的潜力,在解决航空航天高功率密度器件热控制方面具有广泛应用前景.在实验研究的基础上,采用有限体积法对不同体积流量和槽道结构的涡旋微槽中的流动与传热特性进行了数值模拟研究.对涡旋微槽流动的稳定性进行了分析,给出了摩擦因子和Nu数沿流动方向的变化曲线,并采用场协同原理对涡旋微槽强化传热的机理进行了探讨.计算得到的微槽平均传热系数和摩擦阻力系数与实验数据进行了对比.结果表明:涡旋微槽中二次流的出现是涡旋微槽强化传热的机理所在.

Numerical simulation of flow and heat transfer in swirl microchannels

Swirl microchannel heat exchanger has the potential to transfer high density thermal flux. It will have great application prospect in solving thermal control problem of aviation and aerospace high power density component. On the basis of experimental research, a numerical simulation of flow and heat transfer in swirl microchannels was conducted. The computation using the finite volume method was performed under different flux for several test sections with different channel structure. The flow stability in the swirl microchannel was analyzed. The variation curves of local friction factor and Nusselt number along flow channel were presented. The enhancing heat transfer in swirl microchannel was discussed with field synergy principle. The calculated mean heat transfer coefficients and flow friction factors were compared with experimental data. The results show that the secondary flow is the mechanics strengthening heat transfer in swirl micrcochannel.