ABSTRACT This proposal deals with boiling heat transfer in miniature passages that have micro grooves. The miniature passages are rectangular channels with a hydraulic diameter of about 2 mm. There can be sub-millimeter size microgrooves on the inner surfaces of the channels. Experiments using channels with and without microgrooves will be conducted under conditions that will allow the effects of forced convection and capillary action to be delineated. Data to be collected include critical heat fluxes, pressure drops, and thermal resistances for various operating pressures and mass flow rates. Flow visualization will be performed to obtain relevant transport information such as the average lengths and velocities of liquid slugs and vapor bubbles. Mathematical modeling will be carried out to establish the relevant mechanisms for the heat transfer process.
