Abstract
Heat transfer coefficient of water spray cooling of continuous casting was investigated. A steel plate was heated in a furnace and then water spray cooling was applied with various spray nozzles. The change of the surface temperature of the steel plate was measured. The experiments were carried out in the range of the water flow rate from 0.01 to 0.25 l/cm2·min with the surface temperature of the steel plate from 700 to 1200°C. Heat transfer coefficient was calculated using the temperature measurement data of the experiment.
The results obtained are as follows.
(1) Heat transfer coefficient is markedly affected by water flow rate and surface temperature of a steel plate. Heat transfer coefficient can be expressed by the following equation.
h=2.83×107W0.75·Ts-1.2+100
where h is heat transfer coefficient (Kcal/m2·hr·°C), W is water flow rate (1/cm2·min) and Ts is surface temperature of the steel plate (°C).
(2) The effect of water temperature on heat transfer coefficient is not remarkable, and the effect of water pressure, nozzle type and relative position between nozzle and a steel plate is negligible.
