Study on reproducibility of exhaust diffusion properties of gas water heaters

Abstract

When installing a gas water heater in a common corridor, the common way of the installation in Japan, there are restrictions on the installation location and the shape of the corridor in order to avoid the exhaust gas stagnating in the corridor and flowing into the rooms through the vent. Therefore, the standards limit the building planning and require more relaxation. We had been conducting experiments by using full-scale models over the past years, however, as there are many shapes of common corridor, it is difficult to examine all the possibilities. It is necessary to reproduce the exhaust properties on computational fluid dynamics (CFD) so that the examination of reference relaxation can be performed by simulation using CFD. We needed to collect target data to confirm reproducibility by actual measurement. It was ejected without any obstacles to the jet flow, and we measured the velocity, temperature, CO2 concentration, etc. We estimated that the model of the interface on a gas water heater and setting boundary
conditions can be the factors to improve the reproducibility.