An improper air distribution within air-conditioned rooms is one of the largest causes of inadequate indoor air quality and thermal comfort. A good knowledge of the phenomena allows for the advance of eventual deficiencies, thus becoming a powerful tool for the optimization of new projects or for the improvement of the operation conditions of the projects already implemented. In this study two methods were applied, one computational and the other experimental, for modelling of non-isothermal turbulent flows in airconditioned rooms. The computational model consists of a numerical
The necessity of focus on more large integration of passive concepts for indoor climate conditioning is today a reality. Through this study, a contribution to fill the lack of useful design guidelines for natural ventilation is proposed, in order to develop the passive ventilation systems implementation. Besides a methodological approach, the paper proposes conceptual tools. The implementation of a natural ventilation strategy includes the envelope building design, the indoor spaces layout and the
Condensation and mold problems have been identified as one of the severest IAQ problems in Japan. Especially in the wintertime, moisture condenses on cold wall surfaces where it can cause deterioration of the building materials and mold growth related to allergic symptoms. This paper discusses the possibility of using the CFD method to solve condensation problems.
Firstly, a CFD model for simulating condensation is developed, and then the validity of this model is examined experimentally.
The balance between the energy efficient thermal comfort and Indoor Air Quality (IAQ) in healthcare facilities is the main of this paper. The present paper will present this balance from the viewpoint of the air conditioning design. It was found that the design of the HVAC airside systems plays an important role for the energy consumption optimizations and achieving the optimum IAQ. This paper highlights the importance of the proper airside design on the energy consumption, thermal comfort and IAQ.
The present paper addresses and fosters the factors that affect airflow movement and energy efficiencies in the surgical operating theatres. The present work puts forward analyses for major factors contributing to failure to achieve and attain the optimum Indoor Air Quality (IAQ), and the methods suggested to solve such problem. Appropriate architectural and mechanical engineering recommendations to achieve the optimum hygienic operating theatre are set out in the paper.
External shading devices have been utilized very extensively in residential buildings in the tropics to reduce the amount of solar radiation entering into the buildings. However, this will affect the availability of daylight for interior lighting as well as natural ventilation for passive cooling and thermal comfort. This paper discusses the impacts of six different types of external shading device on a residential building in Singapore. The investigation was carried out via the use of LIGHTSCAPE for daylighting simulations and PHOENICS CFD simulations for natural ventilation.
The Loop Equation Design Method has been proposed for sizing ventilation airflow components of natural and hybrid ventilation systems. While the loop design method has been demonstrated on a limited basis, the method has been automated in order to better evaluate its reliability under a more controlled, i.e., less error-prone, environment. This paper describes a computer program that implements the Loop Equation Design Method of sizing the openings of naturally ventilated buildings.
Air infiltration through revolving doors may have significant impact on the heating load of commercial and institutional spaces, and may create discomfort to people. This paper modifies a 40-year old model by Schutrum et al. (1961), composed of two components:
(1) estimation of air exchange between one segment of the revolving door and the indoor/outdoor,
(2) estimation of net air infiltration rate.
Convective air circulation occurring through wall layers is frequently observed in building envelopes. Significant thermal coupling can take place between the incoming cold/warm air and the wall structure, thereby modifying the thermal performances of the envelope. This paper presents an unsteady threedimensional numerical heat and air transfer model, which was developed to
The hygrothermal behavior of a building component exposed to weather is an important aspect of the overall performance of a building. Today the hygric transport phenomena through a building envelope are well understood and a realistic assessment of all relevant effects can be carried out by one of the numerous models and computer programs, that have been developed in different countries over the last years. The calculation of the hygrothermal performance of a part of the envelope is state-of-the-art, but until now, the total behaviour of the actual whole building is not accounted for.