低温微通道等差树形分流数值模拟及实验研究

Numerical simulation and experimental study of equal difference tree shaped diversion in cryogenic micro-channels

针对微通道换热器进出口流量分配与压力损失问题,提出了等差树形分流法,设计了不同分流结构的进出口导流通道,构建了不同分流结构的微通道换热板模型;建立了压力损失理论计算模型,组建了微通道换热器总体三维模型,并进行了流量分配及压力损失数值模拟。制造了不同分流结构的微通道换热器实验模型,并对理论计算模型和数值模型进行了实验验证。研究表明:依据等差树形分流法设计的不同分流结构的导流通道能够解决流量分配不均的问题;提出的压降计算方法能够为不同结构微通道换热器压力损失计算提供依据;梯形分流结构的流量均匀性最佳且压力损失最小。

Aiming at the problem of flow distribution and pressure loss at the inlet and outlet of microchannel heat exchangers,an equal difference tree diversion method was proposed.Different diversion structures of inlet and outlet flow channels were designed,and microchannel heat exchanger plate models with different diversion structures were constructed,a theoretical calculation model for pressure loss was established,a three-dimensional model of microchannel heat exchanger was constructed,and flow distribution and pressure loss numerical simulation were carried out.The experimental models of microchannel heat exchangers with different diversion structures were manufactured,and verified the theoretical calculation model and numerical model through experiments.The research shows that diversion channels with different diversion structures designed based on the equal difference tree diversion method can solve the problem of uneven flow distribution.The proposed pressure drop calculation method can provide a basis for calculating the pressure loss of microchannel heat exchangers with different structures.The trapezoidal diversion structure has the best flow uniformity and the smallest pressure loss.