MODEL EXPERIMENT OF FLOW AND TEMPERATURE FIELD IN ROOM FOR VALIDATING NUMERICAL SIMULATION ANALYSIS OF NEWLY PROPOSED VENTILATION EFFECTIVENESS : Study on evaluation of ventilation effectiveness of occupied space in room

Three indices of ventilation effectiveness are introduced to evaluate a local flow field and contaminant distribution. These are Visitation Frequency (VF ; frequency of contaminant returning back to an objective domain), Tp (average time of contaminant staying in an objective domain) and Local Purging Flow Rate (L-PFR ; air flow rate of a local domain based on the domain averaged concentration). The relationship between VF, Tp, L-PFR and SVEs (Scale for Ventilation Effectiveness) proposed by Kato et al. are theoretically analyzed. Though numerical methods are useful for analysis of VF, Tp and L-PFR, numerical methods are required to validate the results by experimental data since they are based on simplified model of turbulent flow. In order to provide experimental data to validate numerical simulation, measurement of flow fields in a model room was conducted using a LDV (Laser Doppler Velocimetry) system. 10 cases of measurement were conducted where the boundary conditions (1 inlet and outlet position, 2 partitions in the occupied space, 3 temperature condition) are changed. In the measurement, changes in the property of flow fields and temperature distribution are measured in detail. A re-circulating flow (closedcurve mean streamline) was generated in all the cases of the room model. In the cases where the partitions were set in occupied space, mean velocity and the turbulent velocity became larger at the upper part of the cavity and the flow fields became laminar at the lower part of it.