Peak nucleate boiling fluxes for liquid oxygen on a flat horizontal platinum surface at buoyancies corresponding to accelerations between −0.03 and lg_E

Abstract

Abstract Peak nucleate boiling fluxes for liquid oxygen near 1 atm, have been measured on a 0.75‐in.–diameter flat polished horizontal platinum surface located in a known, variable magnetic‐field gradient that produced steady acceleration (which could be maintained indefinitely) on the oxygen acting in opposition to the earth's gravitation, g E . Measurements were made under condition ranging from net negative (directed away from the heated surface) accelerations of −0.03 g E acting on the bulk liquid to the normal accelerations, 1.0 g E . The results indicate that at zero g conditions for the bulk liquid, the peak nucleate boiling flux is ∼0.55 of the value at 1.0 g E . For bulk‐liquid accelerations ranging from ∼0.25 to 1 g E , the experimental results confirm the ¼ power dependence of peak flux on acceleration as predicted by various correlations. However, below 0.25 g E the peak flux becomes insensitive to the acceleration, varying approximately in proportion to the 1/14 power of the net acceleration. At bulk‐liquid conditions of zero g (±0.005 g E ) the peak plux breaks sharply and falls by a factor of 10 between zero g and −0.03 g E (for this apparatus).