Advance Grooved Heat Pipe for Space Satellite Thermal Control System 2009-01-2501
In a near future, telecommunication satellites should be characterized by more and more dissipative payloads and platform. The heat dissipation of the only communication module (CM) could be more than three times higher than the current large satellite payloads. At the same time, the strong restricted requirements to mass and power budget of satellite subsystems lead to choice of mainly passive thermal control system, specifically with heat pipe integration. In such a context, the investigations of existing high performance grooved heat pipes, which are commonly used nowadays for thermal control of telecommunication and scientific satellites, as well as the ways of improve its heat dissipation performance are strongly relevant. This paper is devoted to the R&D of advanced design of grooved heat pipes (GHPs) with thin porous layer (TPL) on its inner surface. As an object for the investigations in this study high thermal performance **GHPs made by EURO HEAT PIPES with Ω shape grooves were chosen. The tested samples have 11 mm in main external diameter (including the size of two ribs) and 1000 mm in the length.
The main goal of this work is to validate by testing the thermal behaviour of the GHPs with and without porous layer. To guaranty the identical boundary conditions, the GHPs samples were tested simultaneously at the same experimental set-up in parallel - classical one and with porous layer in the temperature range between 70 °C and (−30) °C. After the first series of tests it was found, that for all temperature range the evaporator thermal resistance (Re) of GHP with porous layer is lower to compare with Re for classical GHP. The difference in thermal resistances is between 1.3 and 1.8 times (or 0,015- 0,02 W/K for GHP with porous layer and 0,025- 0,035 W/K for classical one). Meanwhile, it was found that the presence of the porous layer in GHP condenser leads to the increasing of the condenser thermal resistance Rcon. Thus the porous coating only in the evaporator zone of the GHP brings the benefit for the cooling capability of the whole device.