Ju Yongfeng, Babaei-Mahani Roohollah, Ibrahem Raed Khalid, Khakberdieva Shoira, Karim Yasir Salam, Abdalla Ahmed N, Mohamed Abdullah, Mahmoud Mustafa Z, Ali Hafiz Muhammad
Faculty of Electronics Information Engineering, Huaiyin Institute of Technology, Huai'an 223003, China.
Department of Chemical Engineering, Brunel University London, Kingston Lane, Uxbridge UB8 3PH, UK.
Nanomaterials (Basel). 2022 May 9;12(9):1605. doi: 10.3390/nano12091605.
This study aims to study the discharging process to verify the influence of geometry modifications and heat transfer flow (HTF) patterns on the performance of a vertical triplex-tube latent heat container. The phase change material (PCM) is included in the middle tube, where the geometry is modified using single or multi-internal frustum tubes instead of straight tubes to enhance the discharging rate. The effects of the HTF flow direction, which is considered by the gravity and opposite-gravity directions, are also examined in four different cases. For the optimal geometry, three scenarios are proposed, i.e., employing a frustum tube for the middle tube, for the inner tube, and at last for both the inner and middle tubes. The effects of various gap widths in the modified geometries are investigated. The results show the advantages of using frustum tubes in increasing the discharging rate and reducing the solidification time compared with that of the straight tube unit due to the higher natural convection effect by proper utilization of frustum tubes. The study of the HTF pattern shows that where the HTF direction in both the inner and outer tubes are in the gravity direction, the maximum discharging rate can be achieved. For the best configuration, the discharge time is reduced negligibly compared with that for the system with straight tubes which depends on the dimensions of the PCM domain.
本研究旨在研究排放过程，以验证几何形状修改和传热流体（HTF）模式对垂直三管潜热容器性能的影响。相变材料（PCM）包含在中间管中，通过使用单截头管或多截头内管代替直管来修改中间管的几何形状，以提高排放速率。还在四种不同情况下研究了由重力方向和反重力方向考虑的HTF流动方向的影响。对于最佳几何形状，提出了三种方案，即中间管采用截头管、内管采用截头管以及最后内管和中间管均采用截头管。研究了修改后的几何形状中各种间隙宽度的影响。结果表明，由于截头管的合理利用产生了更高的自然对流效应，与直管单元相比，使用截头管在提高排放速率和减少凝固时间方面具有优势。对HTF模式的研究表明，当内管和外管中的HTF方向均处于重力方向时，可实现最大排放速率。对于最佳配置，与直管系统相比，排放时间的减少可忽略不计，直管系统的排放时间取决于PCM区域的尺寸。
