LHP thermal control for low temperature (<160K)

Date

7/12/2021

Journal Title

Journal ISSN

Volume Title

Publisher

50th International Conference on Environmental Systems

Abstract

A Loop Heat pipe is an efficient heat transfer system based on the liquid-vapor phase change phenomena. A LHP consists of an evaporator, a condenser, a compensation chamber (also called reservoir), and transport lines. For more than twenty years, Euro Heat Pipe (EHP) and Airbus Defence and Space (ADS) have implemented several developments, in collaboration with product users to cool down dissipative source around [-20�C, +80�C]. Earth Observation missions as well as science missions often require low temperature (close or not to cryogenic temperature) for onboard equipment operation. The use of low Temperature Loop Heat Pipe (LT-LHP) would be a simplest cooling solution for instrument (detectors) and would significantly improve the accommodation, the global instrument architecture and its performances. With this objective EHP/ADS has developed two cryogenic LT-LHPs operating at temperature lower than 160K with two new working fluids: Oxygen and Ethane. The Performances and the LHP ability have to be improved in order to be compliant with the operational temperature range requirements and the storage temperature conditions. For this, two special elements have to be added. Firstly, a secondary evaporator has been added, to limit the heat leaks effect at the reservoir level and decreases the subcooling need of the LHP and also for start-up. Secondly, an additional volume has been placed on the vapor line level to avoid the LHP pressure to reach non acceptable pressure threshold when the temperature is higher than the supercritical state(storage conditions). The following paper provides a concise overview of the development based on classical ammonia LHP and presents the tests realised on LHP with these new working fluids at low temperature and these new components. The following topics are addressed:

  • Requirements needs
  • Concept & Design presentation
  • Performance test results
  • Performance & start-up improvements using secondary evaporator

Description

Typhaine Coquard, AIRBUS DEFENCE AND SPACE
Robin Fornasier, AIRBUS DEFENCE AND SPACE
Barbara Busset, AIRBUS DEFENCE AND SPACE
Quentin Harivel, EHP
St�phane Van Oost EHP
ICES201: Two-Phase Thermal Control Technology
The 50th International Conference on Environmental Systems was held virtually on 12 July 2021 through 14 July 2021.

Keywords

Loop Heat Pipe, Low temperature, design, Performance

Citation