Bubble coalescence during subcooled nucleate pool boiling was investigated experimentally using constant wall temperature boundary conditions while the wall heat flux was measured at a various locations to understand the effects of coalescence on the heat transfer.The observations showed that the coalesced bubble moved and oscillated on the heater surface with significant heat transfer variations prior to departure.Some observations also showed coalescence with no increase in the heat transfer rate.The heat flux for boiling with coalescence fluctuated much more than for single bubble boiling due to the vaporization of the liquid layer trapped between the bubbles.
Abdoulaye CoulibalyLIN XipengBi JingliangDavid M Christopher