STUDY OF INDOOR AIR QUALITY AND THERMAL COMFORT IN A ROOM WITH DISPLACEMENT VENTILATION

摘要

A three-dimensional mathematical model to solve the displacement ventilation is described. The volumetric heat source method is adopted for simulate heat gain and six-flux radiant heat transfer model is introduced in the simulation. The standard k-ε turbulence model is used for predicting indoor air flow patterns, temperature distribution. The Fanger's comfort equations are incorporated in predicting draft risk. The thermal plume and stratification of air in displacement ventilation system are clearly illustrated by numerical results. The results indicated the temperature gradient above the heat source would increase with a higher heat source location. It is also shown that increasing supply air velocity would do good to reduce temperature gradient but this may lead to a higher drat risk in the room with displacement ventilation. Thermal discomfort can be avoided by optimizing the supply air velocity and temperature. These results can be helpful in better understanding and designing this type of ventilation system.