Abstract
The purpose of this study is to develop a high-efficiency underwater plasma discharge boiler for facility horticultural house heating. A plasma discharge heater core using underwater plasma discharge boiler was manufactured using a titanium (Ti) heater core coated with iridium (Ir) and a Polyphenylene Sulfide(PPS) heater unit. Therefore, it was attempted to develop an optimal heater unit by performing life test and leakage voltage analysis. The results are summarized as follows. As a result of the life test of the plasma boiler heater unit, it was found that the PPS heater unit could not withstand the rise in surface temperature due to plasma discharge, and thermal corrosion occurred and the multi-plating layer was destroyed. In the case of the Ti-Ir heater unit, it was found to operate normally without surface corrosion during the life test period. The leakage voltage during plasma discharge of the Ti-Ir heater core showed a tendency to be lower than that in the case where there was no N-phase housing. Also, as the distance between the N-phase housing and the R, S, T phase heater core decreased, the leakage voltage showed a tendency to increase. From the above results, the heater unit of the plasma boiler has a diameter of ø19 mm, a length of 238.5 mm and a center diameter of ø43.9 mm at a 120 degree equal spacing and N-phase housing diameter ø82.5 mm and length 235.5 mm are considered optimal conditions for plasma discharge under the condition of 0.2% (w/v) sodium hexametaphosphate.
Figures & Tables
Fig. 1. Schematic diagram of heater core unit for plasma discharge. (A) PPS heater unit, (B) Ti-Ir heater unit.
