1,720,965 research outputs found
Condensed Combustion Products Analysis of Aluminized Solid Propellants
No full textLERICI, LA SPEZIA, ITAL
Nano-Aluminum as Energetic Material for Rocket Propellants
No full textA characterization of differently sized aluminum powders, by using BET (specific surface measurements), Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), and X-ray Photoelectron Spectroscopy (XPS), was performed in order to evaluate their performance in solid propellant. These aluminum powders were used in manufacturing composite rocket propellants, that are based on Ammonium Perchlorate (AP) as oxidizer and Hydroxyl-Terminated-PolyButadiene (HTPB) as binder. The reference formulation was AP/HTPB/Al with 68/17/15 mass fractions, respectively. The ballistic characterization of studied propellants, made in terms of steady burning rates, showed how better is the performance of nano-aluminized compared to micro-aluminized propellants. Measurements of Al powder ignition time and temperature were also carried out
Nano-Composites for Rocket Solid Propellants
No full textAim of this work is the study of different components (binder and aluminum powders) of solid propellants used for rocket propulsion to improve ballistic performance. New propellant formulations have been tested and characterised. Combustion residues were collected by a proprietary method and analyzed both from the morphological and chemical point of view
Nanoparticles for Solid Rocket Propulsion
No full textThe characterization of several differently sized aluminium powders, by BET (specific surface), EM (electron microscopy), XRD (x-ray diffraction), and XPS (x-ray photoelectron spectroscopy), was performed in order to evaluate their application in solid rocket propellant compositions. These aluminium powders were used in manufacturing several laboratory composite solid rocket propellants, based on ammonium perchlorate (AP) as oxidizer and hydroxil-terminated polybutadiene (HTPB) as binder. The reference formulation was an AP/HTPB/Al composition with 68/17/15% mass fractions respectively. The ballistic characterization of the propellants, in terms of steady burning rates, shows better performance for propellant compositions employing nano-aluminium when compared to micro-aluminium. Results obtained in the pressure range 1–70 bar show that by increasing the nano-Al mass fraction or decreasing the nano-Al size, larger steady burning rates are measured with essentially the same pressure sensitivity
Experimental Investigation and Numerical Modeling of the Condensed Combustion Products of Micro and Nano-Aluminized Solid Propellants
No full textNano-aluminized propellants are investigated and compared with micro-aluminized propellants in order to evaluate the use of aluminum nano-powders for solid rocket applications. Special attention is devoted to the condensed combustion products (CCPs) which significantly affect the solid rocket motor behavior. The experimental investigation performed in this work aims to study the effects of the propellant composition on the formation and evolution of the CCPs; in particular, the influence of oxidizer (AP and AN), particles size distribution (monomodal or multi-modal AP oxidizer), binder nature (HTPB or isoprene rubber) and the aluminum powder size (micro or nano powders) are considered in a compared evaluation. A detailed characterization of the original metal powder is performed in order to investigate the influence on the general behavior of CCPs. A high-speed video recording system is used to visualize the agglomeration formation at the burning surface and their evolution in the gas phase. A chemical analysis (mainly performed with X-ray Photoelectron Spectroscopy technique) is developed in order to measure the aluminum and aluminum oxide content in the quench-collected agglomerates, and to evaluate the combustion efficiency. A X-ray Diffraction technique allows to investigate the CCPs crystalline structure. Under the explored operating conditions, the results confirm that nano-aluminized propellants show larger steady burning rate, without significant change in pressure sensitivity, and lower aggregation / agglomeration phenomena in combustion products. Combustion efficiency is in turn favored by those factors reducing the importance of aggregation / agglomeration phenomena in the combustion process
Experimental Investigations on Transient Burning of Nano-Aluminized Solid Rocket Propellants
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