An experimental investigation of surface effects on nucleate pool boiling of liquid nitrogen from a horizontal surface

Abstract

The effect of various surface conditions on the characteristic boiling curve for liquid nitrogen was experimentally investigated. A circular horizontal flat plate five square centimeters in area was utilized as a boiler surface. The surfaces investigated included mirror finished surface, etched surfaces, and surfaces with .0043 inch diameter artificial cylindrical cavities. Each of these surface conditions was used with Electrical Tough Pitch Copper and Nickel 200 boiling surfaces. The results indicate that surface conditions significantly affect the heat transfer coefficients during nucleate pool boiling of liquid nitrogen. Results from hysteresis data indicate that once boiling sites become active they tend to remain active and produce higher heat transfer rates.