Temperature control using variable conductance closed two-phase heat pipe

Journal Article · Wed May 01 04:00:00 EDT 1996 · International Communications in Heat and Mass Transfer

DOI:https://doi.org/10.1016/0735-1933(96)00028-0· OSTI ID:242211

Sauciuc, I; Akbarzadeh, A; Johnson, P ^[1]

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1. RMIT, Melbourne, Victoria (Australia). Dept. of Mechanical Engineering

The concept of using variable conductance heat pipes (VCHP) for controlling the temperature of solar collectors is introduced. This closed system does not need any external force, is self-controllable and therefore ensures high reliability in thermal control. A copper/water heat pipe equipped with a cold reservoir and buffered with air as non-condensable gas (NCG) has been tested for temperatures from 25 C up to 85 C. Using thermodynamic water properties, the operation of the VCHP is analyzed. Temperature distributions along the VCHP are presented and a simplified model for calculation of the required mass of NCG is included. The model predictions agree well with experimental data. It was found that there is no hysteresis associated with heating and cooling of VCHP. The effect of mass diffusion at the vapor and non-condensable gas interface has been analyzed. Test results show that the starting point of operation for VCHP is mainly dependent on the amount of NCG present in the pipe and on the superheat required for boiling.

• OSTI ID: 242211
• Journal Information: International Communications in Heat and Mass Transfer, Journal Name: International Communications in Heat and Mass Transfer Journal Issue: 3 Vol. 23; ISSN 0735-1933; ISSN IHMTDL
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
HEAT PIPES
HEAT TRANSFER
HYDRODYNAMICS
TEMPERATURE CONTROL
THERMAL CONDUCTIVITY