Aminian Ehsan, Moghadasi Hesam, Saffari Hamid, Gheitaghy Amir Mirza
School of Mechanical Engineering, Iran University of Science and Technology, Tehran 16846-13114, Iran.
Department of Microelectronics, Delft University of Technology, 2628 CD Delft, The Netherlands.
Entropy (Basel). 2020 Sep 9;22(9):1008. doi: 10.3390/e22091008.
Corrugating channel wall is considered to be an efficient procedure for achieving improved heat transfer. Further enhancement can be obtained through the utilization of nanofluids and porous media with high thermal conductivity. This paper presents the effect of geometrical parameters for the determination of an appropriate configuration. Furthermore, the optimization of forced convective heat transfer and fluid/nanofluid flow through a sinusoidal wavy-channel inside a porous medium is performed through the optimization of entropy generation. The fluid flow in porous media is considered to be laminar and Darcy-Brinkman-Forchheimer model has been utilized. The obtained results were compared with the corresponding numerical data in order to ensure the accuracy and reliability of the numerical procedure. As a result, increasing the Darcy number leads to the increased portion of thermal entropy generation as well as the decreased portion of frictional entropy generation in all configurations. Moreover, configuration with wavelength of 10 mm, amplitude of 0.5 mm and phase shift of 60° was selected as an optimum geometry for further investigations on the addition of nanoparticles. Additionally, increasing trend of average Nusselt number and friction factor, besides the decreasing trend of performance evaluation criteria (PEC) index, were inferred by increasing the volume fraction of the nanofluid (AlO and CuO).
波纹通道壁被认为是一种实现强化传热的有效方法。通过使用纳米流体和具有高导热率的多孔介质可以进一步增强传热效果。本文介绍了几何参数对确定合适结构的影响。此外,通过熵产生的优化,对多孔介质内正弦波形通道中强制对流换热以及流体/纳米流体流动进行了优化。多孔介质中的流体流动被认为是层流,并采用了达西-布林克曼-福希海默模型。将所得结果与相应的数值数据进行比较,以确保数值计算过程的准确性和可靠性。结果表明,在所有结构中,增加达西数会导致热熵产生部分增加以及摩擦熵产生部分减少。此外,选择波长为10毫米、振幅为0.5毫米且相移为60°的结构作为进一步研究添加纳米颗粒的最佳几何结构。此外,通过增加纳米流体(AlO和CuO)的体积分数,可以推断出平均努塞尔数和摩擦系数呈增加趋势,而性能评估标准(PEC)指数呈下降趋势。