Gravity Influence of Convective Boiling Stability in a Minichannel

We previously evidenced the influence of confinement and inlet conditions on convective boiling stability in a minichannel. The experiments were realized based on an upward n-pentane two-phase flow. Here, we present results of convective boiling in a minichannel for several minichannel orientations which can be modified from the horizontal (heating surface on the top) through the vertical (previous situation already studied of upward flow) to the horizontal (heating surface on the bottom). We present the results obtained for the same heat flux provided to the minichannel (Q_W = 92 kW.m⁻²), the same range of inlet mass velocity (73 to 2300 Kg.m⁻².s⁻¹) for 5 different minichannel’s orientations: −90°, −45°, 0°, 45° and +90°. The consequences on the minichannel total pressure drop, fluid-wall temperature, and two-phase flow stability are discussed.