THERMAL COMFORT CONDITIONS OF AN INDOOR SWIMMING POOL

Abstract

In this thesis, the thermal comfort and indoor conditions for an indoor swimming pool located in desert climate are investigated numerically. Such climate is characterized by very mild winters, and very hot and sunny summers such as in Qatar. A 17.6 m x 11.7 m indoor swimming pool was studied for an outdoor summer condition of 43.3 ℃ dry-bulb temperature (DBT) and 33.3 ℃ wet bulb temperature (WBT) and for outdoor winter condition of 17 ℃ DBT and 10.6 ℃ WBT. The required design indoor temperatures were taken as 24-29 ℃ all year round and the relative humidity within 50-60% in summer and 40-60% in winter according to ASHRAE Handbook applications (Chapter 6: Indoor Swimming Pools). The calculated pool evaporation rate was 0.005565 kg/s corresponding to latent heat load gain of 13.5 Kw (3.8 TR) to the swimming pool space. Using HAP carrier software, the calculated total thermal load was 61.9 kW (17.6 TR) that needs to be removed from the pool envelope using 1.610 kg/s air flow in summer and 0.560 kg/s in winter. Computational Fluid Dynamics (CFD) simulations were conducted via Ansys Fluent 19.2 1to investigate the recommended indoor conditions limits using standard K- model for turbulence modeling and species transport model for moisture content calculations. A grid independence study was conducted and the final grid consisted of 1869824 elements and 1.2 growth rate. The result of numerical calculation showed the following average values in summer: 24 ℃ air temperature, 0.4 m/s air velocity and 47.7% relative humidity. On the other hand, 24.1℃ air temperature, 0.4 m/s air velocity and 42.1% relative humidity were determined as the average air flow variables in winter season. The results of the numerical calculations were employed in Fanger's thermal comfort model to analyze the thermal comfort sensation of human in the swimming pool space at several heights (y=0.1, 0.6, 1.1 and 1.7 m). The predicted mean vote (PMV) and the predicted percentage of dissatisfied (PPD) are the two indictors that were used in assessing the thermal comfort of occupant. In summer, it was found that people would feel comfortable as the calculated PMV was +0.13 indicting a nearly neutral sensation neither cold nor hot. PPD showed that 5.5% only of occupants felt dissatisfied from the indoor conditions of the swimming pool. PMV of +0.73 indicated slightly warm sensation for people occupying the space in winter season. 84% of occupant felt satisfied while 16% sensed dissatisfied as per the numerical results of indoor condition in winter. The methodology and the results presented in this thesis work can serve as reputable reference and guide for future research related to challenging designs of swimming pools and green houses in desert regions.