Indoor Air Environment

In many parts of Asia as typified by Japan, conditioning of the indoor thermal and air environments using natural ventilation since ancient times. When indoor thermal and air environments are predicted, the use of simulation technologies such as CFD and Heating and Ventilation Network Model has increased. Those have advantages and disadvantages. In addition, AI programs like Neural Network (NN) and Genetic Algorithm (GA) are increasingly utilized in other research areas. In architectural equipment field, there are examples of airconditioning system models with NN.

Traditional method for measuring airborne microbes is based on two procedures called sampling andincubation. Sampling normally involves drawing a sampler from an air stream or room by means ofinstruments based on 3 types collecting-method, which named impaction, liquid impingement andfiltration. Incubation of agar plates typically requires several days.

The ventilation efficiency of different ventilation patterns inside a room containing one person and officefurniture arranged by different inlet/outlet configurations was investigated. The numerical simulation(CFD) was first adopted to predict air flow pattern and ventilation performance. Then, a laboratoryexperimental measurement at room air distribution in a full-scale test chamber was conducted using thehot wire velocimetry (IFA300) to validate the simulation results.

The design of ventilation equipment is important because it affects the ventilation performancedirectly. To improve the ventilation efficiency of the displacement ventilation, a new ventilation system was proposed in this study. The experiment was performed to measure the fume concentration and the visibility at four points under working conditions. In experimental results, the concentration of dust with a new ventilation system was decreased by about 42-60% compared to that of the existing system. The visibility was increased by about 11-18%.