SPRA travel assistance for Edinburgh Napier University student to test polymer based rocket fuel
Late in 2010, the SPRA provided financial travel support for Elisabetta La Scola, a student on the MSc Advanced Materials Engineering programme at Edinburgh Napier University, to help her to travel to Italy to conduct specialised tests on the products of her research work. Under the supervision of Colin Hindle, she was investigating rocket fuel, based on hydroxyl-terminated-polybutadiene (HTPB) as binder and nano-particles of aluminium as metallic filler. Elisabetta is now working for Carlo Gavassi Space SpA in Milan.
Elisabetta’s account of her trip from Edinburgh to Italy to test out her research products is given below.
Short Account of the experimental work in Milan
The fuels investigated for the Final Project “Characterization of Energetic Material as Solid Fuel for Hybrid Rocket”, allowed characterizing of solid fuel ballistic properties through the definition of regression velocity with single and double-slab configuration. In order to perform this test a combustion chamber designed and manufactured at the Solid Propulsion Laboratory of Politecnico di Milano was used. The tests were realized between the 2nd and 5th of November 2010 under the supervision of Professor Luciano Galfetti. All samples were burned in a nitrogen-flushed window bomb ignited by a hot nickel-chrome wire made incandescent by the Joule effect. The hot gases generated by the charge start the ignition of the solid fuel samples when the flow of oxidizer is introduced in the combustion chamber. The measurement of the flow of oxidizer is achieved through an orifice plate. The reading of the change in pressure between upstream and downstream of this constriction allowed to define the inflow. The rate of regression is a measure of the average pressure during the combustion tests and is achieved by using a digital pressure transducer connected to a voltage amplification system, with subsequent acquisition and viewing by oscilloscope. Results showed that the very finely dispersed nano-powder is effective in burning rate enhancement, showing a faster burning rate compared with different compositions. The binder also proved to have a relevant importance in ballistic performance, due to the fact that increasing the percentage of plasticiser in formulation the ballistic properties increase.
Report by Elisabetta La Scola February 2011
