Abstract
In this study, effects of droplet flow density and mean droplet diameter on film boiling heat transfer and collapse temperature of film boiling (MHF point temperature) of spray nozzle cooling were examined experimentally. A test heater was Nichrome foil with 0.2 mm thickness, 5 mm width and 100 mm length. The droplet flow density was 50, 100, and 200 l/min m^2, respectively. The mean diameter of droplet was 198, 301,352,415, and 472μm, respectively. The test heater was heated DC current through DC power supply. The temperature of test heater was measured by using a K-type thermocouple. The present experimental results showed that film boiling heat transfer was increasing with mean droplet diameter. The effect of mean droplet diameter to MHF point temperature was weak. On the other hand, film boiling heat transfer and MHF point temperature increased with increasing droplet flow density.
