Experimental and numerical studies on dynamic thermal performance of hollow ventilated interior wall

摘要

The system integrating hollow ventilated interior wall (HVIW) with solar air collector in residential buildings on Tibetan Plateau facilitates in reducing heating energy use and improving nighttime thermal comfort. In this paper, dynamic thermal performance of HVIW is investigated by experiments and numerical simulations. Experimental results of 3 cases show that heating from the interior wall to the room space lasts during the whole day, and the heat released during the non-ventilation time accounts for more than 40% of the total heat input. Numerical model of this HVIW is validated by experimental results and used to study the influencing factors. Numerical results indicate that the baffle effectively reduces the air short circuit and improves the heat exchange inside the air channel, but resulting in a higher pressure drop. The thicker air channel is averse to the heat transfer inside the channel, while the thicker concrete wall is beneficial to the heat transfer with the increased heat release during the non-ventilation time. With the same ventilation time, the varying inlet air temperature and the intermittent operation significantly increase the total heat released during a whole day and the non-ventilation time. Study of influencing factors in this paper is beneficial to the design of HVIW.