Book Description

ABSTRACT: Heat transfer coefficients have been investigated and it appears that a consequence of gravity independence of ebullition phenomena is a corresponding gravity independent thermal transport two-phase flow-boiling regime. The dependent/independent regime map constructed from experimental data suggests that the analytical bubble dynamics model prescribes a conservative design criterion for the gravity-independent regime. The problem of heat exchanger component burnout has been addressed in the study by measuring the critical heat flux at differing orientations relative to gravity. The data exhibit a strong influence of orientation and suggest that flow orientations without sufficient means to sweep and lift vapor away from the heat transfer surface are subject to considerably lower critical heat fluxes. However, at high velocities, the differences among flow orientations are sharply reduced, suggesting there exists a high velocity region where the critical heat flux is gravity-independent.