International Journal of Heat and Mass Transfer, Vol.39, No.7, 1379-1393, 1996
Boiling of Droplets on a Hot Surface in Low Gravity
The boiling of single droplets of water and n-heptane on a hot stainless steel surface was observed in a low gravity environment, obtained on board a platform in free fall. Droplet impact was photographed using a single-shot flash-photographic method. Surface temperature variation during droplet impact was recorded using a fast-response thermocouple. Droplets could not be maintained in stable film boiling in low gravity : the pressure of vapour under droplets pushed them away from the surface. Nucleate boiling of droplets was not affected by a reduction in gravity. Vapour bubbles nucleating on the solid surface separated and rose into the liquid even in the absence of buoyancy forces.