THERMAL COMFORT AND WIND ANALYSIS OF KHOO TECK PUAT HOSPITAL, SINGAPORE

Abstract

Achieving thermal comfort in a sheltered environment is a perennial problem. Envisioning herself to a sustainable future, Singapore is steering new buildings to adopt natural ventilation as a passive design approach. Confronts with a year by year weather climate and the silver tsunami, there is a strong case to investigate the thermal comfort of a naturally ventilated hospital. A field study of a newly built Khoo Teck Puat Hospital (KTPH) was conducted with an objective of studying the relationship of its wind performance to the thermal comfort of the hospital staff in a naturally ventilated ward area. The methodology involved thermal comfort assessments such as experimental spot measurements and questionnaires surveys of the hospital staff, as well as the wind performance of KTPH using a computational fluid dynamics (CFD) simulation software, Autodesk Flow Design. From the analysis of thermal comfort, it revealed that there was less than 80% of them being thermally satisfied with the current environmental condition, failing to meet the criteria of ASHRAE Standard. In the findings, it was evident that majority of the hospital staff sensed a warmer thermal condition. Besides, a predicted thermal comfort model highlights a relatively low thermal neutrality of 26.3 ͦ C in a naturally ventilated building, which suggest the hospital staff feel more comfortable in a cooler environment. Subsequently, the CFD simulation of KTPH illustrated an average to good wind performance of around 1.30 to 2.75m/s respectively around the tower of the study area with a North-East wind direction. According to the external wind flow simulation results, a prediction of the internal ward areas act as a supporting tool which illustrates the wind performance concerning the thermal comfort findings. The wind performance was predicted to be poor in some sectors that are located away from the windows. This prediction has supported the survey results where the hospital staff have indicated their desire for more air movement. In essence, the thermal environment of the naturally ventilated ward areas of KTPH does not meet the thermal comfort needs of the hospital staff. Hospital staff’s thermal comfort is important because it determines their performance at work. Since the measure of individual’s thermal comfort highly correlates to the productivity level of individual, the author has proposed recommendations such as active and passive control strategies to improve thermal comfort. For instance, portable air coolers and change in building designs are strategies that aid in the enhancement of wind performance in the naturally ventilated ward areas.