Studying the Separating Walls Function in Administrative Spaces on Quality of Air Conditioning and Indoor Airflow Using CFD Method

Document Type : Original Article

Authors

1 Assistant Professor, Department of Architecture and Urbanism, Shahid Rajaee Teacher Training University (SRTTU), Tehran, Iran

2 M.A. in Architecture, Islamic Azad University Khouzestan Science and Research Branch, Ahwaz, Iran

Abstract

It is essential to provide thermal comfort, and to protect the personnel in administrative spaces from adverse conditions of indoor air quality. That is why using air conditioning systems in modern official buildings is prevalent. According to this research and review of literature, these systems typically have no proper operation in cooling inner spaces of administrative spaces with open plan. So, the current study has been performed with the aim of presenting simple and practical techniques in order to promote the quality of air conditioning in official buildings by intervening in current status of architecture and making changes in the structure of some framework elements. This study is a practical research and its methodology is interdisciplinary. A computational fluid dynamic (CFD) method was used and some experimental tests were carried out. At the beginning and after initial observations, a case study was selected randomly. The case was an administrative building in Abadan with an open plan (Yadavaran Project). Using experimental observations and some interviews with the staff, some effective independent variables have been identified. Whereas the dependent variables of the research are indoor airflow directions, its velocity, and the internal temperature. Using some digital devices for measurements was necessary, i.e. some thermometers and two hot wire airflow meters. Accordingly, some test points were chosen and the devices were installed in the right places for the periodic tests. In order to obtain more precise results, some simulation analyses were performed on the case study. The CFD simulations in this research were performed using Gambit and Fluent software programs. The programs were validated using experimental evidence and simulations. The analytical method was implemented using Fluent software to analyze the data. A review of literature indicates that in the late 1930s and early 1940s, there was great interest in the field of air engineering. Several codes were determined in this field around the world. Knowledge of indoor airflow in internal spaces is important for three reasons: thermal comfort, indoor air quality and energy consumption of the building, and in last two decades, the "indoor air flow" emerged in the form of a new knowledge. So this topic and method were employed in this research. The results of this research show that the architectural elements can affect the indoor air quality and its circulations in internal spaces. It can disrupt the comfort conditions of personnel, meanwhile requires more operation of air condition systems in order to cool the rooms, which increases energy consumption. The periodic experimental tests and the simulations show that, the height of the partitions in administrative spaces, their location, and also the position of air diffusers that provide the fresh air in a MVS system must be computed according to the condition of each administrative unit. The architectural planning criteria of similar cases must be carefully reviewed, aimed at improvement of the indoor airflow and its quality. Thus, the energy consumptions can be reduced and the thermal comfort of the staff can be provided more efficiently.

Keywords


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