In Singapore's hot and humid environment, air conditioning has moved from being perceived as comfort to now being a necessity. Buildings usually employ large energy-consuming air systems to condition interior spaces. The use of water-based high-temperature cooling concepts is hard to find due to fears of condensation. The objective of this research is to enunciate the decentralized approach adopted in performing space cooling and dehumidification. The experiment aims at understanding the practicability of using radiant panels with high-temperature chilled water for accomplishing sensible cooling coupled with an independent ventilation system for achieving latent dehumidification. The dew point temperature of air surrounding the radiant panels is monitored to check for condensation. The decentralized ventilation system tested was effective in reducing absolute humidity in air from 22.3 g/kg in outside air to 12.8 g/kg at the under-floor air distribution system's diffuser outlet. The associated dew point temperature and dry bulb temperature measured at the diffuser outlet was 13.9°C and 19.9°C (57°F and 67.8°F), respectively. The measured dew point temperature of air surrounding the radiant panels was 18.3°C (64.9°F), which demostrates the viability of operating radiant panels using high-temperature chilled water to achieve sensible cooling. The air exchange effectiveness of the system running at low supply air velocity was determined to be 1.12, which demonstrates a displacement ventilation system. The air change rates measured per hour using tracer gas techniques ranged between 0.9-2.2 when the supply fan speed was varied between 4000-8000 rpm. The amount of outdoor air thus supplied to the designed space ranged between 0.9-2.1 L/s-m2 (assuming the system ventilation efficiency as 1). These values are above 0.7 L/s-m2, which is the minimum requirement for ventilating office spaces according to Singapore standards.
All Science Journal Classification (ASJC) codes
- Building and Construction