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CNES engineering department has a long experience in space furnace design (GHF, MEPHISTO, MULTIZONE, AGHF etc.) and in the development of their respective experiments. An Expert System (E.S.) known as “CARTOUCHE”** has been developed to check the feasibility and to assist the conception of fusion/solidification experiment cartridges assigned to any axisymmetrical Bridgman type furnace. It will be validated with an ESA furnace, the AGHF (Advanced Gradient Heating Facility), designed for crystal growth and generally for directional solidification experiments up to 1400°C. The furnace consists in a heated section separated from the cooled heat extraction section by a large adiabatic zone. The furnace assembly can be moved along the sample which remains static. So far, five European experiments are to be carried out.

When we want to know temperatures within a system, a thermal model, making occurred the decomposition in several isothermal nodes, is generally used. In the field of space thermal control, conductive conductances intervene at coupling level between the different nodes of thermal models. We have developed a methodology to automatically compute conductive conductances becoming integrated in the thermal chain. The numerical method used to calculate the conductances, is the Boundary Element Method. This method has been tested on a simple example allowing to validate the concept. We also give the main characteristics of the three-dimensional software which is in the process of development.

REBECA-3D (REliable Boundary Element Conductive Analyser in 3 Dimensional) is the software developed by EPSILON INGENIERIE that simulates thermal transfers driven by conductive exchanges. It uses the Boundary Element Method (B.E.M.). It is at the same time a tool of design and a tool of modelling. It gives more accurate and reliable results than classical methods. It allows to carry out a great number of parametric studies with very few calculations. The main bases of this three-dimensional software are given hereafter in order to demonstrate its performances. Firstly, REBECA-3D is applied for an electronic example (in collaboration with ALCATEL ESPACE). Secondly, it is used in a new methodology to automatically compute conductive conductances becoming integrated in the thermal chain.