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The Alpha Magnetic Spectrometer (AMS-02) is a particle physics detector designed to be installed on the International Space Station for at least 3 years, in order to measure charged cosmic rays, and to search for dark matter, missing matter and antimatter. The silicon Tracker is the centre of AMS. It measures particle trajectories through AMS-02 strong magnetic field with a micron accuracy. The heat dissipated by the whole experiment is rejected to deep space by means of four radiators [4–5]: the two Tracker radiators assure the heat dissipation for the above mentioned silicon Tracker, and the two Main radiators reject to space all the heat dissipated by the power, command and control units. The four radiators have been designed, analyzed by means of detailed thermal mathematical models and finally constructed and tested. This paper focuses on the thermal mathematical models tuning to best fit the provided test data.

The Alpha Magnetic Spectrometer (AMS) is a particle physics detector designed to measure charged cosmic rays spectra and high energy photons on board of the International Space Station (ISS). The large acceptance (0.5 m2sr), the long mission duration (3 years) and the state of the art particle identification techniques will allow AMS to provide the most sensitive search up to date for the existence of anti matter nuclei and for the origin of dark matter. AMS02 now is in its final integration phase at CERN. To verify the functional performance of the detectors and of the key subsystems of the Thermal Control System under vacuum condition and to validate the thermal mathematical model of AMS02 a system level thermo-vacuum test will be performed in the Large Space Simulator (LSS) of ESA at ESTEC (the Netherlands).

A Heat Switch has been developed, namely a device able to autonomously regulate its own thermal conductance in function of the equipment dissipation and environmental heat sink conditions. It is based on a Loop Heat Pipe (LHP) technology, with a passive bypass valve which diverts the flow to the Compensation Chamber when needed for regulation purposes. The target application is the potential use on a Mars Rover thermal control system. The paper recalls the Heat Switch design, and reports the results of an extensive test campaign on the ground demonstrator. The performance of the device was found extremely satisfying, and often exceeded the system requirements.

The ASI (Italian Space Agency) AGILE satellite has been launched on April, 23rd 2007 by a PSLV rocket from Shrikariota spaceport, in India. Its payload, called AGILE as well (for Astro-rivelatore Gamma a Immagini LEggero) is an instrument for near-earth space research: its scientific instrumentation has optimal imaging capabilities in both the gamma-ray energy range (30 MeV - 30 GeV) and hard X-ray range (15 - 45 keV). It will study all the phenomena occurring in the high energy spectrum, such as: Active Galactic Nuclei, Gamma Ray Bursts, Gamma-ray Galactic Diffuse Emission, and more. The first 10 months in orbit are reviewed, in light of the thermal control system performance compared with the numerical and experimental predictions.

The future Mars rover thermal design presents a unique challenge to the thermal engineers: the need arises for a thermal control system able to keep rover elements within their operational and non-operational temperature ranges in the face of extreme environmental conditions, characterized by broad day/night temperature excursions, cold biased conditions and long periods in standby modes induced by dust storms. A thermal device is needed, which allows the removal of excess heat from dissipating units during the Martian day and to keep them above their minimum operational/survival temperature during night. Moreover the scientific goals introduce strict requirements in terms of allowable internal components temperature ranges and thermal stability, which the candidate device has to fulfill against wide-ranging power dissipation modes. Such a device has been called Variable Thermal Conductance Device, or ‘Heat Switch’.

The AMS-02 experiment is a space-born instrument designed to perform high precision measurements of cosmic rays and γ-ray fluxes on board of the International Space Station (ISS). All the components of the AMS experiment are designed to withstand the mechanical stresses in the launch phase and to operate in vacuum in a wide range of temperatures. In order to verify the performance of the hardware in harsh conditions like the flight ones, all the components of the AMS instruments undergo a severe qualification procedure before the integration into the detector. In this paper, we will report on the thermo-vacuum tests on the L-TOF (Lower Time of Flight) and ECAL (Electromagnetic CALorimeter) detectors, successfully performed in the SERMS laboratory in June and September 2006, respectively.

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 reports on the thermal testing of AGILE (Astro-rivelatore Gamma a Immagini LEggero) satellite flight model, conducted in June/July 2006 at IABG test facility. The paper describe the satellite mission, the logic for the selection of the test configuration, the test set-up and the test phases. The test results are presented and test-model (of the scientific instruments) correlation analysis between measured and calculated are discussed.

This paper reports on the approach followed for the TCS verification of the payload AMS-02 (Alpha Magnetic Spectrometer), aiming at the qualification of the entire system, in steps, for the space environment. AMS-02 is a state-of-the-art experiment composed by a stack of seven different particle detectors, each of them having its own electronics and control equipments. It will be installed on the International Space Station Starboard segment S3 of the main Truss, and will be a 6500 kg payload, with a power consumption of 2000 W. The verification philosophy is driven by the need to qualify the flight hardware and by the necessary confirmation and correlation of the thermal mathematical models, based on experimental data. The hardware used on AMS-02 is derived from the state-of-the-art ground based detectors for high energy physics, hence not yet proven for operations in vacuum and in extreme thermal environment.

In the paper some methods are presented, with the corresponding practical examples, related to MonteCarlo (MC) techniques for thermal model/test correlation purposes. The MonteCarlo techniques applied to model correlation are intended to be used as an alternative to empirical ‘manual’ correlation techniques, gradients methods, matrix methods based on least square fit minimization. First of all, Design Of Experiments (DoE) tools are used to determine the model response to uncertain parameters and the confidence level of such a response. A sensitivity map is built, allowing the design of the test to maximize the response of the system to the uncertain parameters. Techniques derived from the extreme statistics are used to extrapolate data beyond test limits, with a sufficient confidence in the queue behaviour.

The satellite AGILE (Astro-rivelatore Gamma a Immagini LEggero, “Light Gamma Ray Imaging Detector”) is a promising instrument for near-earth space research of the Italian Space(ASI) during the years 2007-2009: its scientific instrumentation has optimal imaging capabilities in both the gamma-ray energy range (30 MeV - 30 GeV) and hard X-ray range (15 - 45 keV). It will study the phenomena occurring in the high energy spectrum, such as: Active Galactic Nuclei, Gamma Ray Bursts, Gamma-ray Galactic Diffuse Emission, and more. The satellite was designed and built in years 2004-2006; this paper describes the design of the thermal control system of the satellite, with a survey of the flight prediction. As an example of uncertainty reduction, MLI performance characterization by test was done in an early phase of the AIV phase (i.e. well before the system level test), to meet stringent payload requirements in terms of temperature gradients and temperature stability.

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.

In the paper several application techniques of MonteCarlo (MC) method applied to thermal analysis of space vehicles are presented. Although these methods are widely used in other engineering domains, their introduction to the thermal one is quite recent and not fully developed in the industrial practice. This paper aims at showing that, even without demanding computation resources (all what presented has been obtained with a single processor PC) MonteCarlo analysis techniques, in a preliminary design phase, can support and integrate engineering judgment of the thermal designer. In particular, it is exploited the applicability of the method to reduced thermal models, with a clear advantage in terms of computation time. An original approach is proposed, and results are shown. The papers shows the applicability of the MC method to the case when experimental data of the uncertain parameters are available, using the bootstrap re-sampling techniques.

This paper reports on an automated technique for reducing lumped-parameter thermal models. The method is applied in case of a simple geometry (a flat radiator panel), first in steady state conditions and then a comparison in time-variable environment is carried on, assessing how the reduction procedure affects the effective thermal mass of the radiator. More complicated shapes are studied, including concave corners and holes. The technique is implemented by a Matlab® code and it is applied to reduce the heat-pipes- embedded-radiator model of AMS-02, an ISS external payload. The detailed and reduced models behaviour is simulated by SINDA® and the results are compared: existing specification for test-model correlation, regression line and histograms are used for the verification. Furthermore radiator functioning extreme situations are simulated to see the method validity limits in steady state, introducing the concept of ‘working volume’.

Improvements on the thermal analysis for system perturbed by micro-thermal fluctuations are presented: the method applies to any kind of (small) perturbation, in particular to the random ones. Opposite to time domain conventional transient analysis, this method answers the need for frequency domain thermal analysis dictated by the newest scientific missions, with tight temperature stability requirements (expressed in the frequency domain). The small temperature fluctuations allow for assuming any thermal systems a linear one; hence linear system theory holds, and powerful tools to calculate key parameters like frequency response can be successfully employed. MIMO (Multi-Input-Multi-Output) systems theory is applied, the inputs being perturbations to the thermal system (boundary temperatures oscillations and power sources ripple of any shape: pulse, step, periodic, random, …), while the outputs are the temperatures of the sensible parts.

This paper updates on the Thermal Control System (TCS) of AMS (Alpha Magnetic Spectrometer). The Shuttle fleet grounding, after Columbia accident February 2003, has caused a delay in the AMS-02 project schedule, allowing to put additional effort on the TCS design optimization. This paper accounts for two-years extended numerical simulations, leading to a stable TCS baseline design. AMS (shown in Figure 1) is to be installed on the International Space Station (ISS) Starboard segment of the Truss, where it shall acquire data for three years with the Superfluid Helium magnet powered ON. After Superfluid Helium tank is depleted, operations continue taking data with instruments not requiring the magnetic field of the super-conducting magnet; this allows a fine characterization of the spectrum of atoms nuclei, for Solar System human exploration purposes. AMS payload has a mass of about 6500 kg, and a power budget of about 2kW.

The thermal vacuum / thermal balance test design and execution are described in the paper for the qualification campaign of 37 electronic units flown with the payload of ISS (International Space Station), i.e., AMS-02 (Alpha Magnetic Spectrometer). The tests are run in 10 separate test campaigns, across a time frame of 3 years (2002–2005). The tests have been carried on at NSPO (National Space Program Office in Taiwan), maximizing the time usage of thermal vacuum facilities. During each experimental campaign several units are tested at the same time, sharing the vacuum chamber volume. Because independent heaters are applied to each unit, the electronic crates can be tested at temperature levels different from one another. The reliability of thermal analysis is enhanced at each thermal balance test, with the final aim to fully validate the thermal mathematical model deviating less than 3°C from actual measurements.

The paper presents the simulation and the performance evaluation for an innovative Temperature and Humidity Control in a manned orbiting module. Starting from the EcosimPro® modelling capabilities, a Space Station Module has been built and a standard Temperature and Humidity Control (THC) has been designed, based on a classical PID (Proportional, Integral, Derivative) controller, suitably developed. After that, a fuzzy logic controller has been dsigned and thanks to EcosimPro programmability a fuzzy logic controller block has been created. The controller have been sized and its performances suitably simulated. Performances of the innovative controller are checked against the standard control techniques.

Being in charge of the thermal design and analysis for three external payloads that will fly on the ISS (EuTEF, EUROPA and LOBSTER) we highlight in this paper the commonality among them: they are attached to standard adapter plates and have standard resources in terms of power and mass allocation. These payloads, despite these commonalities have specific features due to the different scientific targets, are in different development phases and occupy various locations outside the International Space Station (ISS). Even if thermal requirements are not substantially different the different locations imply different environment and therefore different thermal control solution. Also analytical models of the ISS are different due to ISS development phase and details in proximity of payload location. The paper goes through common thermal design choices and specific solutions adapted to the specific needs of each of them.

This paper reports on the Thermal Control System (TCS) of the AMS-02 (Alpha Magnetic Spectrometer). AMS-02 will be installed on the International Space Station (ISS) Starboard segment of the Truss in 2005, where it will acquire data for at least three years. The AMS-02 payload has a mass of about 6700 kg, a power budget of 2kW and consists of 5 different instruments, with their associated electronic equipment. Analytical integration of the AMS-02 thermal mathematical model is described in the paper, together with the main thermal design features. Stringent temperature stability requirements have been satisfied, providing a stable thermal environment that allows for easier calibration of the detectors. The overall thermal design uses a combination of standard and innovative concepts to fit specific instruments needs.