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Following a comprehensive literature survey about use of Al nanopowders in a range of HEM applications — including rocket propulsion, pyrotechnics, and explosives - a through treatment is offered of the ideal and delivered thermochemical performance of the most interesting metallic ingredients to augment solid and hybrid rocket propulsion. The particular but fundamental class of nAl powders is then investigated in detail: critical issues such as coating and characterization of the powders, rheological and mechanical properties, combustion and ballistic behavior are all examined under a variety of operating conditions. Although attractive for fundamental studies and much used in laboratory experiments, no rocket propulsion operational systems are yet reported in use for nAl powders. Loss of active metal, cold cohesion, and poor propellant castability globally overcome advantages such as increased burning rate (easily achievable by other ways) and reduced specific impulse losses associated with 2P flow (thanks to less agglomeration with respect to the corresponding micrometric powders). Use of dual metallic fuels, by properly blending μAl and nAl, and/or modification of the natural properties of nAl particles, by suitable coatings, represent two possible ways to exploit the potential of nanopowders. Several approaches are also discussed so as to improve dispersion and mechanical properties of solid propellants or solid fuels containing nAl. Overall, a good control of particle size, metal content, and dispersion is a crucial requirement for successful applications of nanoingredients in propulsion

Features such as lowcost, safety, throttleability, and a wide range of appealing applications (e. g., interplanetary landers, boosters for space launcher, upper stage for Vega launcher) make hybrid rocket engines a very attractive option for aerospace propulsion. However, problems such as low regression rates of the solid fuel and low combustion e©-ciency have so far hindered the development of large-scale hybrid rocket engines. Space Propulsion Laboratory (SPLab) at Politecnico di Milano has developed a series of proprietary techniques to evaluate, on a relative grading, the quasi-steady regression rates of solid fuels while visualizing at the same time the §ame structure. Numerical modeling, thermochemical calculations, and mechanical testing complete the range of tools set up to assess the quality of new solid fuels. In this paper, HTPB polymer has been taken as baseline and characterized at laboratory level.

Abstract. Internet progress and the rising interest for developing systems in web environment has given way to several methodological proposals which have been proposed to be a suitable reference in the development process. However, there is a gap in case tool [3][4] [6]. This work presents a case tool named NDT-Tool that allows to apply algorithms and techniques proposed in NDT (Navigational Development Techniques) [2], which is a methodological proposition to specify, analyze and design web information systems.

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