NUMERICAL SIMULATION OF SINGLE-NOZZLE LARGE SCALE SPRAY COOLING ON DRUM WALL.

In this work the single-nozzle spray cooling on a large scale industry-used drum wall has been simulated by a verified numerical model. For a certain spray nozzle, the effects of four parameters, i. e. different spray pressures, different spray heights, different water temperatures, and different wall temperatures, on heat transfer have been analyzed. It is found that the mean heat flux distributions show concentric elliptical circles. Increasing spray pressures will enhance the cooling performance. Decreasing spray heights will improve the heat flux in direct spray areas other than whole simulated drum wall. As expected, reducing water temperature or advancing wall temperature will raise the average wall flux. Both relationships are exponential. The influencing degrees of the four parameters have been compared through Taguchi orthogonal experimental method and the result is: wall temperature > spray pressure > water temperature > spray height. The wall temperature, spray pressure, and water temperature show dominant effects except for the spray height. [ABSTRACT FROM AUTHOR]