The present paper illustrates the main results of an experimental campaign conducted in the Thermal Cavitation. Tunnel of the Cavitating Pump Rotordynamic Test Facility (CPRTF) (it Centrospazio/Alta S.p.A. Experiments were carried out on a NACA 0015 hydrofoil at various incidence angles, cavitation numbers, and freestream temperatures, in order to investigate the characteristics of cavitation instabilities and the impact of thermal cavitation effects. Measured cavity length, surface pressure coefficients, and unsteady pressure spectra are in good agreement with the data available in the open literature and suggest the existence of a strong correlation between the onset of the various forms of cavitation and instabilities, the thermal cavitation effects, and the effects induced by the presence of the walls of the tunnel. Further analytical investigations are planned in order to provide a better interpretation of the above results

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following elliptical orbits only depends on eccentricity e through a standard formula in orbital mechanics [2] 2r" ( 1(1)where /zj is Jupiter's gravitational parameter. We assume that the hyperbolic eccentricity, e h = 1 + rpV^/^j, is just above unity. Indeed, in the Hohmann transfer case (woo « 5.64 km/s), we have e h -1 « 0.018r p /i?j. Also, as we will recall, the S/C can be barely captured; this leads to an energy balance, using-W r .-Ae -AeM sc vl/2 vl/2 e h 1 O(l).

Alta S.p.A. (Italy) and DELTACAT Ltd. (United Kingdom) are conducting a study, funded by the European Space Agency, into the development of hydrogen peroxide monopropellant thrusters using advanced catalytic beds. The present paper focuses on the design of two different demonstration thrusters with nominal ratings of 5 N and 25 N. Design requirements and specifications are presented, followed by the main results of a concept study, which was conducted to define the approximate dimensions needed. Some details about the specific design of the two prototypes and the choice of the main components are provided, with particular regard to the sensors and transducers to be used during the experimentation. Different catalytic bed configurations, including pure silver gauzes and pellets coated with manganese oxide or platinum, are going to be tested in the prototype thrusters, in order to find the optimum one for further industrial development. A dedicated test bench, designed and realized by Alta S.p.A. for tests on the thruster prototypes, is also illustrated.