Abstract
In the first and second reports, visualization experiments were performed using tracer particles and thermo-sensitive liquid crystals. Experiments were also carried out to find the unsteady temperature distribution in a tank when the positively or negatively buoyant jet was injected horizontally in the middle of the tank. One dimensional model for simulating temperature distribution was proposed. The model had applicability to a basic initially uniformed tank temperature. But, by considering an actual equipment, there is a temperature gradient around the jet nozzle, and mixing process is more complicated. In this report, the model was applied for the case of having a temperature gradient around the horizontal jet height. And a modified model, “non-uniformly mixing model" was proposed, which was considered with a vertically mixing process by applying a cubic function for a mixing region. The mixing region was determined by a buoyancy force and a vortex near the wall. The performance of the model was verified by comparing the results with the unsteady temperature distribution obtained experimentally. The model was also compared with the measurements obtained using a commercially available hot water storage system. Both results showed good agreements. Hence adequacy of the model was clarified.
