The Phoenix Hybrid Sounding Rocket Program: A Progress Report 2012

Abstract

The University of KwaZulu-Natal's Phoenix Program aims to develop a hybrid sounding rocket capable of reaching 100 km apogee by 2016. The first stage of the program is the development of the Phoenix-1A low altitude vehicle, capable of delivering a 1 kg payload to an altitude of 10 km. Following intensive structural design and computational analysis work, manufacture of the vehicle is nearing completion. To date, the flight oxidizer tank and motor have been developed, pressure tested, and integrated together by means of four high strength stainless steel struts. The aluminum stabilizing fins have been fabricated and the manufacture of composite airframe components is ongoing. A cold flow test of Phoenix-1A flight motor has been performed. Two hot-fire ignition failures are described and the possible causes discussed. The next immediate objectives of the program are to successfully hot-fire the flight motor by the end of August 2012, and to fly the vehicle by the end of 2012.

Explicit Modelling of the Ignition Transient Structural Response of a Paraffin Wax Hybrid Rocket Motor Fuel Grain

“…Design and test data of rocket motors is necessary to evaluate the use of the defined model parameters, and thus the authors based such inputs on design characteristics associated with sounding rockets of the University of KwaZulu-Natal's Phoenix Hybrid Sounding Rocket Program (Balmogim et al 2015;Genevieve et al 2012Genevieve et al , 2015Leverone et al 2013Leverone et al , 2019. These vehicles are at varying stages of development and are designed with a large variety of desired apogees and research outcomes.…”

“…These scenarios included actual pressure data from available hot-fire tests, the modelled theoretical pressure data based on the HYROPS software estimations (including an estimated pressure spike), and a reduced pressure profile where the chamber pressure does not exceed the design pressure (excluding the pressure spike). All pressure profiles are available in references Balmogim et al (2015), Genevieve et al (2012Genevieve et al ( , 2015 and Leverone et al (2013Leverone et al ( , 2019. It is important to note that the pressure profiles and start-up transients greatly affect the ability of paraffin wax fuel grains to withstand the loads applied, as the material is noticeably strain-rate dependent.…”

“…There was no evidence of any form of failure in this motor after this hot-fire test nor in this ignition simulation, lending validation to the proposed model. In the modelled loading scenario of the P-1A, the artificial pressure spike of 15% (47 bar) (Genevieve et al 2012) over the start-up transient of 0.027 s resulted in grain failure at 0.0243 s. At this time, the material exceeded its maximum allowable stress at the effective strain rate. The maximum equivalent stress at the moment before failure is 3.3 MPa.…”

“…The propellant combination of interest in this research is SASOL 0907 paraffin wax as fuel with nitrous oxide as the oxidiser. This propellant combination is utilised as the primary propulsion mechanism for the University of KwaZulu-Natal's Phoenix Hybrid Sounding Rocket Program (Balmogim et al 2015;Genevieve et al 2012Genevieve et al , 2015Leverone et al 2013Leverone et al , 2019. Additionally, the Phoenix program plans to utilise aluminium powder additives in the paraffin wax at varying percentages to improve the performance and density specific impulse of the motors (Maharaj et al 2016).…”