Search Results

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.

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.

The Combined 2 Phase Loop Experiment (COM2PLEX) is a SPACEHAB rooftop test facility to investigate the 0-g behavior of three different capillary-pumped loops. A flawless operation of these devices under actual space environment is an essential precondition for successful applications of this technology in future space projects. Four European companies have developed COM2PLEX in a co-operative effort under contract to ESA/ESTEC. All capillary pumped loops are of the Loop-Heat-Pipe type. The hardware shall be flown on STS 107, scheduled for launch in March 2001. At the time of writing this paper all loops are in manufacturing or under acceptance testing.

A study has been completed to investigate existing STEP protocols for the purpose of reliable routine CAD data exchange between companies involved in European space projects. The evaluation concentrated on STEP Application Protocols AP-203 and AP-214 because of their broad support and maturity. The study concluded that STEP AP 203 and 214 are sufficient mature to be introduced as CAD data exchange standard in European space industries. In the meantime a working group (WG) promoted by ESA (European Space Agency) has recently been created to establish relevant standards within the European Cooperation for Space Standardization (ECSS). This study has been presented to the WG and is considered as baseline to establish guidelines for product data exchange to be issued.