Parametric Study for Vapor-Liquid Separation in Evaporator of Two-Phase Mechanical pump Fluid Loop System for Lunar and Planetary Exploration



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50th International Conference on Environmental Systems


In recent years, the number of spacecraft components requiring accurate temperature control has increased, and the complexity of thermal design has become a problem. A thermal control system that can accurately control the temperature of multiple devices with a single evaporator is required to simplify the thermal design. We are developing a vapor-liquid two-phase fluid mechanical pump loop system with a large-area isothermal evaporator using a porous wick to meet this requirement. In previous studies, reliable vapor-liquid separation in the evaporator has been an issue. In this study, we improved our previous system and conducted parametric tests. Also, a one-dimensional steady-state model was developed and compared with experiments. As a result, it was shown that vapor-liquid separation could be achieved in the evaporator by positioning the accumulator just before the mechanical pump, reducing the differential pressure in the bypass flow channel installed just before the evaporator, lowering the accumulator temperature below the evaporator outlet temperature.


Rin Asato, Institute of Fluid Science, Tohoku University
Takuya Adachi, Institute of Fluid Science, Tohoku University
Shun Okazaki, Japan Aerospace Exploration Agency
Atsushi Okamoto, Japan Aerospace Exploration Agency
Hiroki Nagai, Institute of Fluid Science, Tohoku University
ICES201: Two-Phase Thermal Control Technology
The 50th International Conference on Environmental Systems was held virtually on 12 July 2021 through 14 July 2021.


two-phase flow, two-phase mechanical pump fluid loop, vapor-liquid separation