航天遥感器用泵驱两相流体回路热真空试验研究

针对航天遥感器核心组件的高精度与高稳定度的控温需求，设计并搭建了一套泵驱两相流体回路(MPTL)试验装置，该装置使用了一套具有被动冷却能力的两相控温型储液器。为验证MPTL系统在高真空、极低温与变化外热流条件下的工作能力，在真空罐内对MPTL系统在不同工况点下的散热与控温能力进行了测试，并通过温度和压力等数据研究了主回路的运行特性、储液器内热力学变化特性及两者之间的传热传质过程。结果表明：MPTL系统的控温点可通过储液器进行快速调整，蒸发器温度的变化受外热流与热源开关影响较小；进入毛细管中的过冷液与储液器中的液相形成的温差保证了储液器冷量的供应；主回路发生相态转变时，储液器与主回路工质交换特性引起了系统压力降脉动。

Thermal vacuum test study of mechanically pumped two-phase loop for space remote sensor

In this paper, a test setup of mechanically pumped two-phase loop (MPTL) was constructed in response to the demand for high precision and high stability temperature control of the core components in space remote sensors. In this setup, a two-phase thermal-controlled accumulator with passive cooling was adopted. For the purpose of verifying the working performance of the MPTL system under the conditions of high vacuum, ultra-low temperature and varied external heat flux, the heat dissipation and temperature control ability of the MPTL system under different test conditions were tested in the vacuum chamber. Then the obtained test data, including temperature and pressure, were used to analyze the operating characteristics of the main loop, the thermodynamic behaviors in the accumulator and the heat and mass transfer between the main loop and the accumulator. The test results showed that the temperature control points of the MPTL system could be quickly adjusted by the accumulator, and the external heat flux and the action of starting up and powering off of the heat source had little influence on the temperature of the evaporators. The cooling capacity was provided by the temperature difference between the subcooling liquid entering the capillary tube and the liquid phase in the accumulator. During the phase transition in the main loop, the mass transfer behaviors between accumulator and the main loop gave rise to the pressure-drop oscillations.