A computational fluid dynamics study on the effects of computer fan on indoor airflow and indoor air quality in breathing zone

Abstract

Although desktop computers have been considered in many computational fluid dynamics (CFD) indoor simulations, they were usually simplified as hot boxes. A real desktop computer, however, is not only a heat source but also a momentum source due to the jet airflow generated by the computer case fan. The airflow induced by a desktop case fan could have the same order of magnitude as the ventilation rate of the whole room, and thus is expected to have significant influence upon the indoor airflow field and distribution of contaminants. Obviously, the simplification of desktop computer into a hot box does not sufficiently stand for the actual situation. In this study, a CFD model of a typical office room was built and simulations were conducted to investigate the airflow field and volatile organic compounds (VOC) distribution under two scenarios: (1) computer as a ‘hot box’ without a fan and (2) a more realistic computer model with an operating case fan. The comparison of CFD results yielded from these two scenarios demonstrated that the role of computer fan is very important in terms of airflow field and contaminant distribution and should be included in CFD office simulations for the purpose of improved reliability.