In order to improve nano‐aluminized solid propellant properties and performance, different materials are being investigated for coating nano‐aluminum particles. Two of the powders which are considered are V‐ALEX, a fluoropolymer (Viton) coated nano‐aluminum, and L‐ALEX, a stearic acid coated nano‐aluminum. It is believed that a thin layer of coating should protect the aluminum core from premature oxidation, as well as provide an exothermic source which may accelerate particle ignition, resulting in reduction of agglomeration. This paper investigates the effect on the agglomeration phenomenon of replacing 33 % of the micron aluminum powder with ALEX, V‐ALEX and L‐ALEX powders, in solid propellant samples containing 20 % HTPB, 65 % AP and 15 % aluminum. Propellant strands were burned inside a windowed pressure chamber, allowing measurements of the agglomerates size and number using a high‐speed camera. The experimental data showed that propellants in which 33 % of the micron aluminum was replaced with nano‐powders exhibited reduced agglomeration, in terms of number of agglomerates and their total volume. The reason is the lower ignition time and temperature of the nano‐powders that ignite before aggregating to agglomerates. The propellants containing ALEX nano‐powder exhibited a reduction of up to 36 % in agglomerates volume compared to the propellants containing only micron powder, while the propellants containing coated nano‐powders, L‐ALEX and V‐ALEX, showed a higher reduction of up to 60 % in agglomerates volume. V‐ALEX showed slightly better performance than L‐ALEX. It can be concluded that by replacing some of the micron‐aluminum with coated nano‐aluminum in solid propellants, it is possible to significantly reduce the propulsive losses due to agglomeration.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.