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A concept for a miniature, mechanically pumped two-phase cooling loop with high thermal performance was developed. In this feasibility study, a miniature, annular gear pump was inserted into the liquid line of a two-phase LHP-type loop architecture. In contrast to capillary-pumped systems, the functions of liquid pumping and evaporative heat transfer were separated and could be optimized independently. The cooling system was tested in terms of heat transport capability, performance and stability using water as the working fluid. The results show a high heat transfer coefficient of >11 W/(cm2K), a high heat transport capability of >70 W/cm2, and stable working behavior in all orientations. These results were obtained with a device using a simple loop architecture and an evaporator design that was not optimized for this kind of operation.

This paper will give an overview of the effort to develop a thermal engineering tool for space applications, which is based on open source software (OSS) tools. It will describe the architecture of the analysis system and discuss the considered OSS packages used as building blocks with respect to the integration aspect and the engineering capabilities. The discussion of the software is completed with the experiences in creating a web-based community.

Development, fabrication and launch of the German X-ray satellite ABRIXAS has been implemented as a pilot project in order to minimize program costs by introducing new management, procurement and verification methods. For the thermal control subsystems key issues are the early project involvement of thermal engineers in an integrated team, a competitive procurement policy without rules imposed by the customer and a verification philosophy which combines extensive thermal analysis with a reduced thermal test program involving critical components and a spacecraft system test. Besides these subjects the paper includes a description of design verification of critical units by analysis and thermal balance tests.

Loop heat pipes (LHP) combine the classical heat pipe operation principle with a loop configuration, i.e. evaporator and condenser are located at separate places as dictated by thermal and configurational reasons and are connected lines for fluid and vapor transport. Experimental investigations of such LHP revealed certain temperature oscillations under certain conditions. This paper presents the results of analyses of such temperature fluctuations and offers possible explanations for initiation and termination of such behavior. Two types of temperature fluctuations have also been confirmed experimentally by testing different kinds of LHP.

This paper outlines and compares the thermal control design and thermal accommodation of the batteries of various European communications satellites, viz the ESA spacecraft OTS, ECS, MCS, and Olympus, the German, French and British national programs: DFS-Kopernikus, TV-SAT, TDF1 and Skynet IV, and the Inmarsat II maritime comms satellite. The performance of these battery thermal control systems is discussed versus their specific design features using flight results or analytical predictions as available. A conclusion is drawn with respect to achievements versus investments and an outlook is attempted on development trends.