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MITA is one of the ASI standard platforms for scientific missions. Its demonstration mission was launched the 15th July 2000 from Plesetsk by means of a COSMOS rocket. According to the technological qualification goal of the mission, it was possible to use the spacecraft operations for the thermal design performance characterization; so doing several measurements were available as correlation points with the thermal model. At the end of the thermal model validation campaign an attitude control strategy was implemented in order to maximize the time used for scientific observations. In particular precious data were collected in order to reduce the modeling uncertainties in the MITA satellite’s family, whose first commercial mission is scheduled for 2003, carrying a gamma- ray telescope. In its first mission the MITA platform was carrying a particle detector called NINA, contained in a pressurized vessel.

An experimental campaign is presented aiming at the characterization of thermal dissipation of batteries to be used on board of small satellites. A suitably designed device allows to manage automatically the orbital cycling simulation between battery cell charge and discharge. The cell thermal performance is characterized in various combinations of temperature, discharge current and Depth of Discharge. The gathered data are used for providing guidelines in the design of a family of Italian Small Satellites.

This work proposes a focus on the simulation of a rotative volumetric expander via a CFD code. A customized application of OpenFOAM® has been developed to handle the particular motion of the calculation grid. The model uses a mesh to mesh interpolation technique, switching from a calculation grid to the new one on the basis of mesh quality considerations performed on the fly. This particular approach allows to account for the presence of leakages occurring between the stator and blade tips and also occurring at the top and bottom of the vanes. The fluid considered is the refrigerant R245fa, whose particular properties have been determined resorting to the NIST database. Experimental data, measured at different conditions of mass flow and fluid temperature, are compared to calculation results. Moreover, the CFD analysis has allowed the estimation of the influence of the leakage mass flow occurring at the tip of the vanes on the overall machine performances.