Field Measurement and Estimation of Ventilation Performance of Solar Chimney

-Performance Estimation of Natural Ventilation in Actual Building based on Measurement of Ventilation Rate-

Abstract

Solar chimney, which is a natural ventilation device that enhances the stack effect due to solar radiation has been studied for decades, by using an experimental method, a Computational Fluid Dynamics (CFD) method, and a multi-zone model method. However, the field measurement data of actual buildings with a solar chimney seem to be insufficient. The aim of this study is to accumulate the knowledge about solar chimneys, and to establish a prediction and estimation method for the natural ventilation performance. The performance of the solar chimney at an actual city hall with a natural ventilation system is presented in this paper. The airflow rate and air change time per hour (ACH) were estimated in the spring of 2018, and were compared with the values predicted during the designing phase; it was found that the estimated ACH was approximately 10 h^-1, which was 1.5 times the predicted value. The airflow rate and ACH were averaged each month; in April 2018, the averaged airflow rate through the solar chimneys was 1,424m³ min^-1. In addition, the frequency distributions of ventilation rate through the solar chimney, i.e. the usage level of the solar chimney were obtained.