R1336mzz(E) の水平平滑管外における流下液膜蒸発

抄録

This study experimentally investigated the heat transfer coefficients and flow patterns of falling film evaporation of HFO refrigerant R1336mzz(E) as test refrigerant on a horizontal smooth tube with outer diameter of 19 mm. The experiments were carried out at a saturation temperature of 15 °C and film Reynolds number range of 50-1000. In the experimental conditions, the droplets, disturbed columns, and discrete droplets were observed. There was no difference in the transition of the flow pattern due to the heat flux. The heat transfer coefficients dramatically decreased due to the increase in the dry patch area at low film Reynolds number region. The dry patch area increased with increasing heat flux at the low film Reynolds number region. At the low heat flux condition, the heat transfer coefficient increased as the film Reynolds number decreased except for the region where dry patches occurred. The heat transfer coefficients were enhanced with increasing heat flux due to promotion of nucleate boiling.