Experimental study on turbulent flow and heat transfer in an air to water heat exchanger using perforated circular-ring
Experimental study on turbulent flow and heat transfer in an air to water heat exchanger using perforated circular-ring
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DOI：
10.1016/j.expthermflusci.2015.09.002
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发表时间：
2016
影响因子：
3.2
通讯作者：
M. Sheikholeslami;M. Gorji-Bandpy;D. Ganji
中科院分区：
文献类型：
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作者：
M. Sheikholeslami;M. Gorji-Bandpy;D. Ganji
在本研究中，对空气-水双管换热器中的传热和压力损失进行了实验研究。典型的圆环（TCR）和穿孔圆环（PCR）湍流器放置在环形管道中。工作流体是在环形管中流动的空气和流经内圆管的水。实验针对不同的控制参数进行，即：气流雷诺数（6000–12,000）、节距比（1.83、2.92和5.83）和穿孔数量（0、2、4和8）。根据实验数据给出了摩擦系数、努塞尔数和热性能的相关性。结果表明，由于速度场和温度场之间的夹角减小，使用 PCR 导致比 CR 获得更低的传热增强。热性能随着N的增加而增加，但随着雷诺数和节距比的增加而降低。
In this study, heat transfer and pressure loss in an air to water double pipe heat exchanger are experimentally investigated. Typical circular-ring (TCR) and perforated circular-ring (PCR) turbulators are placed in annular pipe. The working fluids are air, flowing in the annular pipe, and water through the inner circular tube. The experiments are conducted for different governing parameters namely; air flow Reynolds number (6000–12,000), pitch ratio (1.83, 2.92 and 5.83) and number of perforated hole (0, 2, 4 and 8). Correlations for friction factor, Nusselt number and thermal performance are presented according to experimental data. Results indicated that using PCRs leads to obtain lower heat transfer enhancement than the CRs because of reduction of intersection angle between the velocity and the temperature field. Thermal performance increases with increase ofNbut it decreases with increase of Reynolds number and pitch ratio.