Numerical investigation of turbulent flow heat transfer and pressure drop of AL2O3/water nanofluid in helically coiled tubes
Numerical investigation of turbulent flow heat transfer and pressure drop of AL2O3/water nanofluid in helically coiled tubes
复制标题
螺旋管内 AL2O3/水纳米流体湍流传热和压降的数值研究
DOI：
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发表时间：
2015
期刊：
影响因子：
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通讯作者：
A. Rezk
中科院分区：
文献类型：
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作者：
A. Elsayed;R. AL;S. Mahmoud;A. Rezk
被动对流传热增强可以通过改善工作流体的热物理性质、改变流动几何形状或两者兼而有之来实现。这项工作提出了一项数值研究，以研究使用螺旋线圈和纳米流体对湍流流态中的传热特性和压力损失的综合影响。开发的计算流体动力学模型根据已发表的实验数据和经验相关性进行了验证。结果表明，在相同雷诺数下，纳米氧化铝（Al2O3）与盘管相结合的效果比直管内纯水的传热系数提高了60%。此外，结果表明，使用体积分数为3%的Al2O3纳米流体的螺旋线圈中的压降是直管中水的六倍（压降增加的80%是由于纳米颗粒的添加），而雷诺数对压降惩罚因子的影响并不显着。
Passive convective heat transfer enhancement can be achieved by improving the thermo-physical properties of the working fluid, changing flow geometry or both. This work presents a numerical study to investigate the combined effect of using helical coils and nanofluids on the heat transfer characteristics and pressure losses in turbulent flow regime. The developed computational fluid dynamics models were validated against published experimental data and empirical correlations. Results have shown that combining the effects of alumina (Al2O3) nanoparticles and tube coiling could enhance the heat transfer coefficient by up to 60% compared with that of pure water in straight tube at the same Reynolds number. Also, results showed that the pressure drop in helical coils using Al2O3 nanofluid for volume fraction of 3% was six times that of water in straight tubes (80% of the pressure drop increase is due to nanoparticles addition), while the effect of Reynolds number on the pressure drop penalty factor was found to be insignificant.