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The EC (Experiment Container) FASES (Fundamental and Applied Studies on Emulsion Stability) is an ESA scientific payload dedicated to the investigations of emulsion stability. FASES will fly in the FSL (Fluid Science Laboratory) rack in the ISS Columbus module. The challenging requirements are the minimum temperature (−50°C) to be reached and the cooling rate to be achieved (2°C/min) for three different types of samples with an accuracy of 0.1°C. The identified solutions are two active temperature control devices based on thermo-electric coolers (TEC): a Thermostatic Chamber (THC) that manages two type of samples (ITEM-S and ITEM-F) a mini-calorimeter (CAL) that handles the third one (EMPI). Considering the operative ranges, a multi-cascade TEC has been selected to fulfill the requirements. The performance of a multi-cascade TEC made up of separate single stages is also investigated.

This paper describes the thermal modeling and analyses performed on the LISA Technology Package (LTP), with special attention to the frequency domain requirements on the sensitive instrumentation. The new approach is presented, and the modeling and analysis phases are described in detail. Results about LTP thermal stability in the frequency domain are shown, and obtained though two alternate approaches. The first one consists in the study of the transient response of the system to a periodic input with a frequency equal to the minimum frequency of interest, using the well known low-pass filtering properties of the thermal systems. The second is based on the generation of a time dependent input, starting from its Power Spectral Density definition: this input is used to run a transient thermal analysis and finally transform its results into the frequency domain. Thermal stability assessment studies have been performed also at spacecraft level and are well described in [ref. 3].

Four different thermal-vacuum tests were performed on AMICA Star Tracker (AST) in the period March-July 2006 in the space simulator of the SERMS laboratory in Terni-Italy. Each of these tests was designed to verify different AST camera design features. The Thermal Balance test was conceived to validate the thermo-elastic model of the instrument and the active and passive thermal control subsystems. The Thermal Vacuum Cycling test was conceived to validate the AST electronics operative and survival temperature limits under vacuum conditions. The worst hot and cold operative and survival limits of the lens and filters in the AST optical system were assessed by means of the “Sun in the lens” and Lens Cold tests.

This paper describes the Thermal Balance test that has been performed on EuTEF (European Technology Exposure Facility) platform, to be flown in October 2007 as an attached payload of Columbus module to the ISS. The thermal control system of EuTEF is based on a passive concept, with several different payloads being each one a self-standing technological experiment, with a centralized power supply and data handling. Each instrument has its own TCS, independent one another: they are individually insulated by MLI. The test has been performed with EuTEF Flight Model (FM) on the Passive Attach System to have representative thermal flight-like interfaces. Simulation of close-to-real flight environmental heat loads have been accomplished in a vacuum chamber (at INTESPACE, Toulouse-F) by means of a solar beam and a spin table suitably oriented to simulate a critical identified orbit, among all the possible on the ISS.

This paper describes the Thermal Balance test that has been performed on the PAMELA telescope Pressurized Container (PC) to verify the performance of the PC Thermal Control System (TCS). The PC will be attached outside the Russian satellite RESOURS DK to be flown in2004 The thermal control system of the PAMELA PC is based on a mechanical pumped loop fed with Isooctane as working fluid. The test has been performed with PAMELA Structural Thermal Model (STM) inside the PC to have representative interfaces for the thermal control system. Simulation of close-to-real flight environmental heat loads have been accomplished in a vacuum chamber by means of a complex system of IR lamps suitably oriented toward the PC and mechanically mounted on a tubular structure outside the PC. Overall test results have been excellent; PAMELA thermal control system thermal/fluidic requested performance have been verified. PAMELA telescope thermal interfaces have been confirmed as well.