特斯拉阀型微通道热沉换热强化的数值研究

Numerical Investigation of Heat Sink with Tesla Valve Type Microchannel

由于受到空间的限制,微电子领域的散热设备必须满足体积小、效率高等特点。微通道热沉因其优良的特性,能够满足微电子设备的散热要求,目前已得到广泛运用。随着微电子技术的发展,电子设备的集成度越来越高,为了设备能够高效平稳运行,对散热提出了更高的要求。由于特斯拉型通道包含了分叉结构,当冷却流体流经时分叉结构可以增强对流体的扰动,达到增强换热的目的。本文采用数值模拟的方法,对特斯拉阀型微通道热沉的强化换热进行研究。改变特斯拉阀型通道级数、特斯拉阀弧形通道外侧半径以及特斯拉阀的设置方向,得到不同几何参数下特斯拉阀型微通道热沉底面的温度分布、平均温度和冷却流体的进出口压降,从而研究其换热特性和流动特性。当特斯拉阀级数为12,特斯拉阀弧形通道外侧半径为750μm时,微通道热沉的散热效果最好。当冷却流体流量小于5 mL/min时,特斯拉阀正向设置的散热性能及流动性能均优于逆向设置;当冷却流体流量大于5 mL/min时,特斯拉阀逆向设置的散热效果优于正向设置,但需要以更大的流体压降为代价。

The microelectronic cooling devices must satisfy the characteristics of small volume and high efficiency,etc.due to the space limitation.With the excellent heat transfer performance,at present,the microchannel heat sink has been widely used in microelectronic field.With the development of microelectronic technology,the degree of integration of electronic equipment becomes higher and higher.In order to meet the stable operation of the equipment,higher requirements for heat dissipation are put forward.Because Tesla type channel contains bifurcate structure,when the cooling fluid flows through it,the bifurcate structure can enhance disturbance to the fluid so as to achieve the goal of enhanced heat transfer.In the present paper,numerical simulations were used to investigate the heat transfer enhancement of Tesla valve type microchannel heat sink.By changing stage number of Tesla valve,the outer radius of arc channel and the placement direction of the Tesla valve,the temperature distribution and the average temperature on the bottom of heat sink as well as the pressure drop at inlet and outlet of the cooling fluid were obtained under different geometric parameters to study its heat transfer characteristics and flow characteristics.It was found that when the number of stages of the Tesla valve was 12 and outer radius of arc channel was 750μm,the heat sink of the microchannel had the best heat dissipation effect.When the flow rate of the cooling fluid was less than 5 mL/min,the heat dissipation and flow performance of the heat sink were better than the reverse setup;When the flow rate of the cooling fluid was larger than 5 mL/min,the heat dissipation effect of the reverse setup was better than forward setup at the expense of larger pressure drop.