{"title":"Experimental study of the influence of pad angle on the thermal performance of a direct evaporative cooling system","authors":"M. Mehrabi, K. Goudarzi, S. Davoodabadi Farahani","doi":"10.1007/s44189-023-00041-9","DOIUrl":null,"url":null,"abstract":"Abstract One of the most important parts of direct evaporative cooling systems is the cooling pad. Pads vary in materials and construction features. The parameters studied in the performance of the pads are air speed, pad thickness, geometrical characteristics, and its configuration and the provided water flow rate. The performance of the pads is usually determined through saturation efficiency, pressure drop, temperature drop and humidity increase in the treated air, evaporation and water consumption, cooling capacity, coefficient of performance, and heat and mass transfer coefficients. Since the geometry and how to place the pad in the evaporative cooling system is one of the most important issues related to the performance of such systems, the present work experimentally investigates the amount of cooling and evaporation of the direct evaporative cooling system under 5 different angles of placement of the cellulose pad in relation to the vertical position. It includes angles of $$0^\\circ$$ <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"> <mml:msup> <mml:mn>0</mml:mn> <mml:mo>∘</mml:mo> </mml:msup> </mml:math> , $$5^\\circ$$ <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"> <mml:msup> <mml:mn>5</mml:mn> <mml:mo>∘</mml:mo> </mml:msup> </mml:math> , $$10^\\circ$$ <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"> <mml:msup> <mml:mn>10</mml:mn> <mml:mo>∘</mml:mo> </mml:msup> </mml:math> , $$15^\\circ$$ <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"> <mml:msup> <mml:mn>15</mml:mn> <mml:mo>∘</mml:mo> </mml:msup> </mml:math> , and $$20^\\circ$$ <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"> <mml:msup> <mml:mn>20</mml:mn> <mml:mo>∘</mml:mo> </mml:msup> </mml:math> in 5 different air speeds, 2 different inlet water flow rates, 2 inlet air temperatures, and 2 different inlet water temperatures. Results show that the lowest output temperature, highest air relative humidity, highest coefficient of performance (about 12% more than $$0^\\circ$$ <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"> <mml:msup> <mml:mn>0</mml:mn> <mml:mo>∘</mml:mo> </mml:msup> </mml:math> ), highest saturation efficiency, and highest evaporation rate are obtained in the case of a $$15^\\circ$$ <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"> <mml:msup> <mml:mn>15</mml:mn> <mml:mo>∘</mml:mo> </mml:msup> </mml:math> of cooling pad placement angle.","PeriodicalId":13757,"journal":{"name":"International Journal of Air-conditioning and Refrigeration","volume":null,"pages":null},"PeriodicalIF":0.8000,"publicationDate":"2023-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"International Journal of Air-conditioning and Refrigeration","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1007/s44189-023-00041-9","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"THERMODYNAMICS","Score":null,"Total":0}
引用次数: 0
Abstract
Abstract One of the most important parts of direct evaporative cooling systems is the cooling pad. Pads vary in materials and construction features. The parameters studied in the performance of the pads are air speed, pad thickness, geometrical characteristics, and its configuration and the provided water flow rate. The performance of the pads is usually determined through saturation efficiency, pressure drop, temperature drop and humidity increase in the treated air, evaporation and water consumption, cooling capacity, coefficient of performance, and heat and mass transfer coefficients. Since the geometry and how to place the pad in the evaporative cooling system is one of the most important issues related to the performance of such systems, the present work experimentally investigates the amount of cooling and evaporation of the direct evaporative cooling system under 5 different angles of placement of the cellulose pad in relation to the vertical position. It includes angles of $$0^\circ$$ 0∘ , $$5^\circ$$ 5∘ , $$10^\circ$$ 10∘ , $$15^\circ$$ 15∘ , and $$20^\circ$$ 20∘ in 5 different air speeds, 2 different inlet water flow rates, 2 inlet air temperatures, and 2 different inlet water temperatures. Results show that the lowest output temperature, highest air relative humidity, highest coefficient of performance (about 12% more than $$0^\circ$$ 0∘ ), highest saturation efficiency, and highest evaporation rate are obtained in the case of a $$15^\circ$$ 15∘ of cooling pad placement angle.
摘要冷却垫是直接蒸发冷却系统中最重要的部件之一。护垫的材料和结构特点各不相同。研究了气速、垫层厚度、几何特性、垫层结构和所提供的水流量等参数对垫层性能的影响。通常通过饱和效率、被处理空气中的压降、温度下降和湿度增加、蒸发和用水量、冷却能力、性能系数和传热传质系数来确定垫片的性能。由于几何形状和如何放置垫在蒸发冷却系统中是与这种系统的性能相关的最重要的问题之一,因此本工作实验研究了纤维素垫在垂直位置的5种不同放置角度下直接蒸发冷却系统的冷却量和蒸发量。它包括$$0^\circ$$ 0°、$$5^\circ$$ 5°、$$10^\circ$$ 10°、$$15^\circ$$ 15°和$$20^\circ$$ 20°的角度,有5种不同的空气速度、2种不同的进水流速、2种进水温度和2种不同的进水温度。实验结果表明,该装置的最低输出温度、最高空气相对湿度、最高性能系数(约为12% more than $$0^\circ$$ 0 ∘ ), highest saturation efficiency, and highest evaporation rate are obtained in the case of a $$15^\circ$$ 15 ∘ of cooling pad placement angle.
期刊介绍:
As the only international journal in the field of air-conditioning and refrigeration in Asia, IJACR reports researches on the equipments for controlling indoor environment and cooling/refrigeration. It includes broad range of applications and underlying theories including fluid dynamics, thermodynamics, heat transfer, and nano/bio-related technologies. In addition, it covers future energy technologies, such as fuel cell, wind turbine, solar cell/heat, geothermal energy and etc.