Variable Conductance Heat Pipes (VCHPs)
ACT (Advanced Cooling Technologies)
Passive spacecraft thermal control devices combining two-phase working fluid with a Non-Condensable Gas reservoir to automatically regulate evaporator temperature across wide power and sink condition ranges.
Typed specifications7 values
Discloses 1 of 7 fields engineers filter by in this category (category median 2).
- Envelope (L×W×H)
- Down to 2 mm thickness Low Profile · datasheet p.4
- Radiation tolerance (TID)
- 600 krad max · Total Ionizing Dose (TID) · datasheet p.5
- Export status
- EAR datasheet p.11 ITAR
- Product type
- heat pipe datasheet p.8 variable conductance heat pipe VCHP; variants: cold reservoir, hot reservoir, thermo-modulating
- Flight heritage
- NASA planetary lander programs including Peregrine and VIPER description
Each value is typed with its unit and measurement condition and cites the datasheet page it was taken from. Nothing is guessed: a field that is absent here has not been published by the manufacturer. machine-extracted ✓ checked by NewSpace Market ✓ manufacturer confirmed by the manufacturer.
As published by the supplier4 lines, in the manufacturer's own wording
- Effective thermal conductivity
- 10,000 to 100,000 W/m·K
- Control method
- Passive (Non-Condensable Gas)
- Material systems available
- Aluminum-ammonia; Copper-monel/water; Sodium-Haynes
- Quality certification
- ISO 9001:2015, AS9100D
About
Variable Conductance Heat Pipes (VCHPs) extend standard heat pipe technology by incorporating a Non-Condensable Gas (NCG) reservoir, enabling the device to passively regulate evaporator temperature without any active control systems or moving parts. As power or sink conditions change, the NCG expands or contracts within the condenser section, blocking or opening varying lengths of condenser area.
At high power levels, elevated vapor pressure drives the NCG into its reservoir, opening the complete condenser for maximum heat transfer. As power decreases, vapor pressure drops, allowing the NCG to expand and partially block the condenser. Thermal conductivities span 10,000 to 100,000 W/m·K.
ACT manufactures VCHPs in multiple material-fluid combinations: aluminum-ammonia for standard spacecraft temperatures, copper-monel/water for microgravity systems, and sodium-Haynes for high-temperature applications. ACT has delivered flight hardware for NASA planetary lander programs including Peregrine and VIPER.
Documentation
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