Accession Number : AD0657025

Title :   CRYOGENIC HEAT PIPE.

Descriptive Note : Final technical rept.,

Corporate Author : AIR FORCE FLIGHT DYNAMICS LAB WRIGHT-PATTERSON AFB OHIO

Personal Author(s) : Haskin,W. L.

Report Date : JUN 1967

Pagination or Media Count : 61

Abstract : A heat pipe is a metal tube containing a two phase fluid to transport heat over several feet by evaporating liquid at the warm end and condensing the vapor at the cold end. An experimental heat pipe was constructed and instrumented to permit measurements of the heat transport in a nitrogen vapor tube wherein the vapor pressure and boundary temperatures could be monitored. No major effort was made to optimize the performance of the tube tested, but various designs and operating parameters were investigated experimentally to determine their effects on the thermal impedance of the tube. Heat loads of up to 130 watts were transferred axially in this 3/4-inch OD, 33-inch-long heat pipe with less than half the total temperature drop required by a copper rod of comparable size. The main temperature drops in the heat pipe are due to heat conduction through the tube wall and the fluid filled wick liner of the evaporator and condenser sections. When the tube surface temperatures were near the critical temperature of nitrogen, vapor film formation caused a large temperature drop. (Author)

Descriptors :   (*HEAT TRANSFER, *CRYOGENICS), (*PIPES, HEAT TRANSFER), TWO PHASE FLOW, EVAPORATION, CONDENSATION, NITROGEN, VAPOR PRESSURE, GAS FLOW, INSTRUMENTATION

Subject Categories : Air Condition, Heating, Lighting & Ventilating
      Test Facilities, Equipment and Methods
      Thermodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE