Politeknik Dergisi 2147-9429 Gazi Üniversitesi 10.2339/politeknik.517603 Engineering Mühendislik Performance Analysis of Thermal Storage Assisted Cooling Tower with Night Cooling Performance Analysis of Thermal Storage Assisted Cooling Tower with Night Cooling https://orcid.org/0000-0002-0043-2941 Toprak Kasım IZMIR INSTITUTE OF TECHNOLOGY, FACULTY OF ENGINEERING, DEPARTMENT OF MECHANICAL ENGINEERING (ENGLISH) https://orcid.org/0000-0002-1615-1693 Ouedraogo Kiswendsida Elias IZMIR INSTITUTE OF TECHNOLOGY, FACULTY OF ENGINEERING, DEPARTMENT OF ENERGY SYSTEMS ENGINEERING 12 01 2020 23 4 1027 1035 01 25 2019 10 03 2019 Copyright © 1998, Politeknik Dergisi 1998 Politeknik Dergisi

Asglobal warming and water scarcity issues continue to grow, it is essential toincrease resources efficiency for air conditioners and power plants. In orderto increase the efficiency, the systems need to be modified to take theadvantages of the low night temperature and thermal storage tanks. In thisstudy, the low night temperature and thermal storage tanks effects on thecooling tower is studied using TRNSYS. Using a chiller operating from 8:00 to16:00 as a case study, hot water from the condenser is partially stored ondaytime and cooled slowly during the night. The storage tank volume isoptimized by considering two big tanks and five small tanks. The results showthat night cooling reduces cooling water temperature by 5.8 °C or 21.8% whilethe cooling efficiency is increased by 36%. The thermal storage tanks enable tohave the low continuous flow rate and help to reduce the fan power by 67.1%. Onthe storage side, compared to two tanks system, the tanks volume is reduced by16.5% when 5 tanks are used. In theory this reduction can go up to 50% byincreasing the number of tanks and reducing their individual size.

Asglobal warming and water scarcity issues continue to grow, it is essential toincrease resources efficiency for air conditioners and power plants. In orderto increase the efficiency, the systems need to be modified to take theadvantages of the low night temperature and thermal storage tanks. In thisstudy, the low night temperature and thermal storage tanks effects on thecooling tower is studied using TRNSYS. Using a chiller operating from 8:00 to16:00 as a case study, hot water from the condenser is partially stored ondaytime and cooled slowly during the night. The storage tank volume isoptimized by considering two big tanks and five small tanks. The results showthat night cooling reduces cooling water temperature by 5.8 °C or 21.8% whilethe cooling efficiency is increased by 36%. The thermal storage tanks enable tohave the low continuous flow rate and help to reduce the fan power by 67.1%. Onthe storage side, compared to two tanks system, the tanks volume is reduced by16.5% when 5 tanks are used. In theory this reduction can go up to 50% byincreasing the number of tanks and reducing their individual size.

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