Latent heat storage is a kind of heat storage technology and heat is charged or discharged through phase change, melting or solidification, respectively. Authors proposed a direct heat exchange system between granulated phase change material (PCM) and air. PCM is consisted from granulated porous media and paraffin. Its particle diameter is about 1〜3mm. Advantage of this system is that heat transfer coefficient is kept relative large and continuous during phase change. In this investigation, column experiments related with heat exchange between PCM and air were conducted. Also, a computer simulation program was made and phase change period was discussed by the proposal non-dimensional time.
