Iranian Society of Heating, Refrigerating, and Air Conditioning Engineers (IRSHRAE) Journal of Renewable and New Energy 2423-4931 8 2 2021 09 23 Investigation of Phase Change Materials Selection in Passive Cooling to Improve Natural Ventilation and Thermal Comfort Investigation of Phase Change Materials Selection in Passive Cooling to Improve Natural Ventilation and Thermal Comfort 1 10 122200 FA Seyed Hossein Neshat Safavi MSc student, Architecture Department, Imam Khomeini International University, Qazvin, Iran Seyed Ragman Eghbali Associate professor, Architecture Department, Imam Khomeini International University, Qazvin, Iran Journal Article 2020 03 09 The cooling energy has covered most portion of building energy consumption in hot and arid climates. Accordingly, suppling of required energy for cooling systems as well as passive solutions to reduce air temperature are so noticeable. As an effective factor, Phase change materials through changing phase save energy and help to improve natural ventilation as well as thermal comfort. These materials have various types base on their chemical structure and melting point. In this way, optimal PCM selection base on their application and melting point is very important; so that, improve natural ventilation and cooling energy in buildings. This study investigates the properties and behavior of phase change materials for their implementation in building passive cooling systems as well as natural ventilation by reviewing and analyzing valid researches and documents in hot and dry climate of Yazd city. Finally, due to PCMs type, their application, and climate condition, optimal PCM has been found; so that, provide thermal comfort, energy consumption reduction, and natural ventilation. As a result, PCM with melting point of 28 ° C can put the environmental temperature in the thermal comfort zone; besides, improve thermal comfort conditions and natural ventilation. The cooling energy has covered most portion of building energy consumption in hot and arid climates. Accordingly, suppling of required energy for cooling systems as well as passive solutions to reduce air temperature are so noticeable. As an effective factor, Phase change materials through changing phase save energy and help to improve natural ventilation as well as thermal comfort. These materials have various types base on their chemical structure and melting point. In this way, optimal PCM selection base on their application and melting point is very important; so that, improve natural ventilation and cooling energy in buildings. This study investigates the properties and behavior of phase change materials for their implementation in building passive cooling systems as well as natural ventilation by reviewing and analyzing valid researches and documents in hot and dry climate of Yazd city. Finally, due to PCMs type, their application, and climate condition, optimal PCM has been found; so that, provide thermal comfort, energy consumption reduction, and natural ventilation. As a result, PCM with melting point of 28 ° C can put the environmental temperature in the thermal comfort zone; besides, improve thermal comfort conditions and natural ventilation. https://www.jrenew.ir/article_122200_a97128b2cee3740cff5214a20043a259.pdf