, 43:30 | Cite as

Thermal analysis of building roof assisted with water heater and insulation material

  • D Prakash


Traditional roof systems are constructed with concrete and weathering coarse layer and these roof systems absorb and reflect a certain amount of solar radiation. The absorbed solar energy is transferred into building indoor and causes significant discomfort to the occupants. Also, this solar energy gets dissipated without any useful energy conversion. Hence this paper is focused to use the available solar energy effectively through a novel solar water heating system and the transfer of heat in the building indoor is arrested by proper roof insulation material. The modified insulated roof with the solar water heater is designed and simulated numerically in commercial computational fluid dynamics code with validation. Through this study, the factors that affect the performance of solar water heating system and thermal insulation capacity are analysed and the best design of the modified roof system is identified. The modified roof system produces 25 L of hot water per day with a temperature raise of 60°C in the winter season. Also, the same roof system maintains the ceiling temperature at about 27°C for a complete day in a summer season.


Thermal analysis building roof solar water heating system roof insulation numerical simulation 

List of symbols


pipe diameter


polyurethane layer thickness


wood wool layer thickness


refractory carborundum brick layer thickness


ambient temperature




solar radiation


temperature of the combined effect of radiation and convection


indoor temperature


thermal conductivity of ceiling


convective heat transfer coefficient of the exterior surface of the roof


convective heat transfer coefficient of indoor


water outlet temperature


ceiling temperature


mass flow rate


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Copyright information

© Indian Academy of Sciences 2018

Authors and Affiliations

  1. 1.School of Mechanical EngineeringSASTRA Deemed UniversityThanjavurIndia

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