Department of Mechanical Engineering, Urmia University of Technology (UUT), P.O. Box 57166-419, Urmia, Iran.
Environ Sci Pollut Res Int. 2021 Jun;28(24):31778-31791. doi: 10.1007/s11356-021-12947-1. Epub 2021 Feb 21.
Due to growing demand for potable water, the improvement of fresh water production systems such as conventional solar stills is a crucial issue. Conventional solar stills are one of the simplest methods of the production of fresh water from saline water; however, they are fairly low-performance devices. Since oxygen is a paramagnetic gas, the humid airflow in a conventional solar still can be controlled by an externally imposed magnetic field. Therefore, this paper presents the effect of magnetic field on the performance improvement of a conventional solar still as a novel technique. The governing equations of the problem are discretized by the finite volume method. The impacts of the applied magnetic field arising from a multilayer solenoid on the streamlines patterns, temperature and mass fraction contours, the production rate of water ([Formula: see text]), and the average heat transfer rate (Nu) are presented at five specified times (cases). The influences of important factors such as intensity (0≤NI≤100000) and location of the magnetic field (X=0.15, 0.49, and 0.83) on the heat and mass transfer rates are explored. It is found that the production rate of water and heat transfer rate are increasing functions of magnetic field intensity. For the applied magnetic field with NI = 10and X = 0.83 m, water productivity and convective heat transfer rate can be increased by about 43%, 38%, 41%, 40%, and 48% for cases 1, 2, 3, 4, and 5, respectively.
由于对饮用水的需求不断增长,提高淡水生产系统(如传统太阳能蒸馏器)是一个关键问题。传统的太阳能蒸馏器是从盐水生产淡水的最简单方法之一;然而,它们的性能相当低。由于氧气是顺磁性气体,因此可以通过外加磁场来控制传统太阳能蒸馏器中的湿空气流。因此,本文提出了磁场对传统太阳能蒸馏器性能提高的影响,这是一种新颖的技术。问题的控制方程通过有限体积法离散化。在五个指定时间(案例)展示了多层螺线管产生的磁场对流线模式、温度和质量分数轮廓、水的产量([Formula: see text])以及平均传热速率(Nu)的影响。探讨了磁场强度(0≤NI≤100000)和磁场位置(X=0.15、0.49 和 0.83)等重要因素对传热和传质速率的影响。结果表明,水的产量和传热速率是磁场强度的增函数。对于施加的磁场,NI = 10 和 X = 0.83 m,对于案例 1、2、3、4 和 5,水的生产率和对流传热速率分别可以提高约 43%、38%、41%、40%和 48%。