Parametric Investigation of a Hybrid Motor Using Paraffin and Nitrous Oxide

Shani Sisi
Work towards M.Sc. degree under the supervision of Prof. Alon Gany
Faculty of Aerospace Engineering
Technion – Israel Institute of Technology

Hybrid rockets may present a good propulsion alternative for different missions, in particular for the emerging space tourism, mainly due to the safety of the motor both during development and operation. Nevertheless, for certain applications the low regression rate of conventional polymeric fuels implies too low thrust. In recent years, paraffin (wax)-based fuels have been investigated because of their much higher regression rate compared to that of polymeric fuels. Paraffin, however, presents relatively poor mechanical properties.

This study aims at experimental investigation of plain paraffin and HTPB-reinforced paraffin fuels with nitrous oxide (N2O) oxidizer via static firing tests of a lab scale hybrid motor. Polymethyl-methacrylate (PMMA, Plexiglas) fuel is tested as well for reference data. A comparison to results from the literature for similar fuels with oxygen as the oxidizer is also done to indicate influencing properties of the specific oxidizer. It was found that regression rate of paraffin is about five times higher than that of PMMA (polymer). A mixed paraffin-polymer (HTPB) fuel gives a lower regression rate than pure paraffin, yet it is higher by about 2-3 fold than that of PMMA. Characteristic velocity efficiency obtained was in the range of 80-100%, with an average of about 90%. The use of oxygen as the oxidizer was found to yield higher regression rate due to its higher flame temperature.

The talk will be given in Hebrew

Wed, 09-07-2014, 16:30 (Gathering at 16:00)

Classroom, ground floor, Library, Aerospace Eng.

Light refreshments will be served before the lecture

Parametric Investigation of a Hybrid Motor Using Paraffin and Nitrous Oxide