Pressure Recovery in a Cylindrical Heat Pipe at High Radial Reynolds Numbers and at High Mach Numbers

摘要

The pressure recovery in a cylindrical heat pipe has been investigated. The experiments cover average radial Reynolds numbers between 5 and 150 and average Mach numbers up to the velocity of sound. During preliminary experiments in a cylindrical, gravity-assisted heat pipe at high Mach numbers large condensate flow instabilities were observed. As a consequence the heat pipe power varied strongly. Based on these observations an improved heat pipe design was made that resulted in steady operating conditions throughout the entire parameter range. This heat pipe is described. The pressure recovery was measured and compared with results from a two-dimensional analytical model for describing compressible vapor flow in heat pipes. Good agreement with the experimental data was found. (ERA citation 10:028305)