Energy saving and thermal comfort studies of a regional air-conditioning mechanism

Abstract

Making the workroom a more pleasant, comfortable, healthy, safe, and energy-efficient place is an important goal. This article presents an airflow management technique that uses a regional air-conditioning mechanism (RACM) to control the airflow in the workroom with the aim of achieving a regional steady-state temperature. This concept means that each member of staff in a different area of the location can be satisfied with respect to their own local environment. A system of RACM consists of a main duct with an upper round inlet port and a lower round outlet port that was located in the centre of a cylindrical room. In simulations for this study, the change of the distance between the inlet and outlet ports as well as that of the heights of the inlet and outlet ports were considered in order to obtain the optimal airflow, temperature distribution, and thermal comfort indices in the occupied zone. The computational fluid dynamics simulation results predict that the RACM could successfully establish a regional air-conditioning cell, an individual thermal comfort zone, and also that RACM can be inferred to be more energy efficient than a typical air-conditioning system. The concepts in this study are relevant to all kinds of regional air-conditioning in any enclosed space.

Keywords

energy saving thermal comfort regional air-conditioning airflow management temperature distribution

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