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The paper describes the design, development and testing of a Heat Transport System (HTS) for a Laser Communication Terminal (LCT) on the TerraSAR-X satellite. The HTS is based on the technology of Loop Heat Pipes (LHP) with variable heat conductance capability. Which maintains for this specific LCT payload component a constant temperature with a very small tolerance within a ≤0.5K range. For this new and challenging application an actively controlled bypass with a flow control valve has been developed. In a conventional application the valve works in a passive mode, i.e. it actuates automatically according to the saturation pressure of the loop's heat carrier fluid. With increasing evaporator temperature (or saturation pressure) the valve opens the bypass line in order to divert vapour from flowing to the radiator. If the evaporator temperature decreases then the valve regulates again an increasing flow to the radiator.

This paper provides schematics of two-phase devices with the following main distinctions: 1. Application of auxiliary evaporator for startup from supercritical state. 2. Absence of usual reservoir or compensation chamber. Results of modeling of such devices, and also results of experimental testing are submitted.

Loop Heat Pipes (LHP) emerge as standard equipment for spacecraft thermal control. Based on a co-operation agreement between TAIS, Moscow and OHB-System AG, Bremen several thermal control projects for Mars mission, ISS and small satellites have been initiated, which are all based on loop heat pipes. The thermal control systems, described in this paper, are currently under development or hardware manufacturing. The paper will detail the application scenario, development steps and first test results.

The Netlander mission aims to deploying on the surface of Mars a network of 4 landers, which will perform simultaneously measurements in order to study the internal structure of Mars, its sub-surface and its atmosphere. This paper describes the phase B thermal control concept of the Netlander Surface Module, taking into account various thermal environments from the cruise to Mars phase until the landing and the one Martian year phase on the Mars surface. The paper focuses on two specific thermal tests. The first one is a thermal conductivity measurement of three pre-selected insulation materials in a 6 - 10 hPa CO2 environment, and the second one is a performance test of a Loop Heat Pipe designed to comply the Netlander Surface Module needs. This paper is mainly derived from the report referenced ref. 1.

Present paper's purpose is to describe three Thermal Control Systems (TCSs) on base of Loop Heat Pipes (LHPs) that were realized in frame of “Mars-96” program. The main problems that were solved during the TCSs elaboration and some terrestrial tests' results will be also presented here below.