Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : June 24, 2020 - June 26, 2020
Thermosiphon utilizing vapor bubble pumping, which can realize the heat transfer from the upper part to the lower part without the utility power source, has been studied intensively. However, some problems have been left for the practical use. One of the problems is unstable heat transfer, that is, intermittent circulation flow rate of working fluid, which happens in the condition of small solar radiation in morning and evening. This phenomenon, which causes equipment failure, was investigated by the field experiment using model house. Hence, a thermosiphon control system to realize the stable heat transfer, namely almost constant flow rate of working fluid is proposed. This is achieved by means of reducing the pressure of working fluid to lower the boiling point. In this report, the feasibility of the proposed control method is confirmed by the model experiment in the field. The experimental result demonstrates that almost constant flow rate of working fluid can be realized by reducing the pressure to lower the boiling point.
