Thermal performance of building element containing phase change material (PCM) integrated with ventilation system – An experimental study

• A new design of heat storage unit for building applications has been proposed.
• Heat storage unit is made of a gypsum composite containing phase change material.
• A set-up for experimental investigation of heat storage unit was developed.
• Temperature variations of air flowing through the ceiling panel were measured.
• Heat transfer process between air and gypsum-PCM composite was analyzed.

In this paper a new structure of a ceiling panel is described and its thermal performance is presented. The idea is to build a ceiling in the form of thick board with parallel internal channels for air flow. It is also important that a ceiling is made of a composite containing about 27% of phase change material (PCM). Such a ceiling would be a part of a building ventilation system – air taken from the environment flows through the channels and exchange heat with the construction material. When a melting point of PCM is properly chosen it is possible that the temperature of air flowing into the building reach a level corresponding to thermal comfort conditions, regardless the temperature at the intake. Warm air (during a day) release the heat basically to PCM causing its melting. During night time cool ambient air is heated up while it takes back heat accumulated in PCM. An experimental set-up based on the above concept was developed. A series of tests in different conditions (inlet air temperature, air flow rate) were performed. Information on thermal performance of the ceiling panel as well as detailed data on heat transfer process were obtained and discussed in the paper.