Analysis of a rotary passive heat recovery device for natural ventilation windcatcher

Based on the design of traditional architecture, windcatchers are devices which provides passive ventilation by manipulating pressure differentials around buildings induced by the movement of wind and difference in temperature. In temperature climates, it is effective in providing passive cooling during summer months. However, during winter months, the low air temperature supplied to the space can cause further thermal discomfort and increase heat loss which lead to higher energy consumption. This limits the capabilities of windcatchers to provide ventilation all year round. To address this issue, the present study proposes incorporating a rotary thermal heat recovery device into the windcatcher channel and investigate its performance using numerical modelling and experimental tests. The study focused on characterizing the design and performance of the copper radial blades of the proposed heat recovery device. The predicted results of the airflow and temperature showed good agreement with the experimental tests. Two types of radial blade designs were assessed in terms of the airflow velocity and distribution, the pressure drop and the heat recovery performance.