Convection heat transfer of CO2 at supercritical pressures in a vertical mini tube at relatively low reynolds numbers
Convection heat transfer of CO2 at supercritical pressures in a vertical mini tube at relatively low reynolds numbers
复制标题
超临界压力下 CO2 在垂直微型管中以相对较低的雷诺数进行对流换热
DOI：
10.1016/j.expthermflusci.2008.05.006
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发表时间：
2008-09-01
影响因子：
3.2
通讯作者：
Shi, Run-Fu
中科院分区：
文献类型：
--
作者：
Jiang, Pei-Xue;Zhang, Yu;Shi, Run-Fu
通过实验和数值研究，研究了超临界压力下 CO2 在 0.27 mm 直径垂直微型管中在相对较低入口雷诺数（2900 和 1900）下向上和向下流动的对流换热。研究了入口温度、压力、质量流量、热通量、流动方向、浮力和流动加速度对对流传热的影响。对于小于 2.9 x 103 的入口雷诺数，在高热通量 (113 kW/m(2)) 下，两个流动方向的局部壁温呈非线性变化。对于当前研究中使用的微型管，即使加热相对较强，浮力效应通常也较低，而加热引起的流动加速会强烈影响湍流并减少高热通量的传热。对于相对较低的雷诺数（Re-in
Convection heat transfer of CO2 at supercritical pressures in a 0.27 mm diameter vertical mini tube was investigated experimentally and numerically for upward and downward flows at relatively low inlet Reynolds numbers (2900 and 1900). The effects of inlet temperature, pressure, mass flow rate, heat flux, flow direction, buoyancy and flow acceleration on the convection heat transfer were investigated. For inlet Reynolds numbers less than 2.9 x 103, the local wall temperature varies non-linearly for both flow directions at high heat fluxes (113 kW/m(2)). For the mini tube used in the current study, the buoyancy effect is normally low even when the heating is relatively strong, while the flow acceleration due to heating can strongly influence the turbulence and reduce the heat transfer for high heat fluxes. For relatively low Reynolds numbers (Re-in