ISSN Online: 2379-1748
ISBN Flash Drive: 978-1-56700-469-4
ISBN Online: 978-1-56700-470-0
Second Thermal and Fluids Engineering Conference
COOLING ENHANCEMENT OF DROP IMPACT ON FLOWING LIQUID FILM
要約
A water drop impacts a thin heated wafer which is being cooled by a film flow generated from water jet
impingement. The drop impact breaks the steady-state cooling and causes the local temperature around the
drop landing location to change. Based on the surface temperature measurement, the surface temperature
quickly decreases, and then recovers to the steady state. To evaluate the change of convection, an enhancement
factor (η) based on the change of heat transfer coefficient is introduced. When most of the impact area reaches
its local maximum enhancement (ηmax), the distribution of ηmax along the centerline of the impact area is
referred as the maximum enhancement curve, and the peak value of the curve is referred to as the peak
enhancement (ηp). It is found ηp does not follow a monotonic trend with increasing the impact velocity, but
ηp increases with increasing the drop diameter and decreasing the flowing film rate.