Saturated nucleate pool boiling of oxygen under magnetically-enhanced effective gravity

TL;DR

This study explores how increasing effective gravity via magnetic forces affects saturated nucleate pool boiling of oxygen, finding no significant change in boiling behavior across a gravity range of 1g to 16g.

Contribution

It demonstrates that magnetic enhancement of gravity does not alter the boiling curve of oxygen within the tested range, providing new insights into boiling under variable gravity conditions.

Findings

Superheat scales with heat flux as a cube root at low flux.

Superheat becomes linear with heat flux at higher flux.

No significant change in boiling behavior across 1g to 16g effective gravity.

Abstract

We investigate the effect of enhancing gravity on saturated nucleate pool boiling of oxygen for effective gravities of 1g, 6.0g, and 16g (g=9.8 m/s^2) at a saturation pressure of 760 torr and for heat fluxes of 10 ~ 3000 W/m^2. The effective gravity on the oxygen is increased by applying a magnetic body force generated by a superconducting solenoid. We measure the heater temperature (expressed as a reduced superheat) as a function of heat flux and fit this data to a piecewise power-law/linear boiling curve. At low heat flux (<400 W/m^2) the superheat is proportional to the cube root of the heat flux. At higher heat fluxes, the superheat is a linear function of the heat flux. To within statistical uncertainties, which are limited by variations among experimental runs, we find no variation of the boiling curve over our applied gravity range.