College of Agriculture, Engineering
and Science (CAES)

Clockwise from left: Mr Thabang Mdhluli; Dr Sarisha Harrylal and Mr Jordan Silver; and a SAFFIRE liquid rocket engine hot-fire test at Denel Overberg Test Range.

Master’s Research Propels Graduates into Aerospace Careers

UKZN’s Aerospace Systems Research Institute (ASRI), one of the largest aerospace research groups in the country, is celebrating the graduation of three of its master’s students and engineers, Mr Thabang Mdhluli, Mr Jordan Silver and Dr Sarisha Harrylal, who have conducted ground-breaking work on injector design, liquid rocket engine performance, and roll control systems to drive South Africa’s growing aerospace industry forward.

At ASRI, Mdhluli is responsible for designing, manufacturing and assessing test equipment for developing gelled rocket propellants. Originally from Mpumalanga, he pursued his undergraduate and master’s degrees at UKZN to expand his perspective and exposure to different cultures and ideas. UKZN’s reputation for academic excellence also drew him in, and he found the new environment with knowledgeable staff and like-minded students stimulating.

Always fascinated with how things work, Mdhluli’s curiosity about mechanical components and interest in problem-solving and designing solutions led him to mechanical engineering for its wide range of applications.

His master’s focused on developing a rocket injector test rig to visualise the spray generated by the injector elements for image processing to obtain valuable data to facilitate optimum injector design. Injector design is a crucial factor in the overall performance of aerospace propulsion systems, and Mdhluli’s work provides a platform to study injection and impingement characteristics of gel propellants through a single-element injector, allowing for droplet characterisation and qualitative analysis. This formed part of broader research into the behaviour of gelled rocket propellants.

He effectively managed his time by dividing his research into smaller management tasks that he regularly reviewed and adjusted. He also worked as a teaching assistant for thermodynamics at UKZN while completing his master’s, ensuring he compartmentalised his responsibilities to achieve a balance.

A student member of the American Institute of Aeronautics and Astronautics (AIAA) and the Aeronautical Society of South Africa (AeSSA), Mdhluli presented his research at the AIAA SciTech conference in January 2024 in the United States of America and published his conference paper.

He plans to continue working as an aerospace engineer with ASRI, focusing on creating robust, reliable and efficient test systems that are critical for ensuring the safety and performance of aerospace components. His work involves designing and implementing custom LabVIEW applications seamlessly integrating with National Instruments hardware, enabling precise data acquisition, control and analysis.

He thanked his supervisors, Professor Michael Brooks and Mr Timothy Velthuysen, for their guidance and support; family for their love, encouragement and support; members of ASRI for the advice and insightful discussions that broadened his perspectives; the Department of Higher Education and Training (DHET) Nurturing Emerging Scholars Programme (NESP); Department of Science and Innovation (DSI); and ASRI for their funding and support.

Silver also completed his undergraduate and master’s studies at UKZN, choosing the institution for its strong reputation for mechanical engineering excellence, value for money and proximity to home. His relationships with staff, students and colleagues in the mechanical engineering discipline kept him at UKZN for postgraduate studies, as did ASRI’s thrilling research offerings.

With a knack for fixing things and a passion for cars and sports car racing, mechanical engineering was a natural choice for someone who wanted to learn the ins and outs of vehicles and pursue a career in these industries.

For his master’s (awarded cum laude), Silver conducted a performance comparison between the gas generators and electrically pumped rocket engines under ablative and regenerative cooling on ASRI’s South African First Integrated Rocket Engine (SAFFIRE) liquid rocket engines. This allowed ASRI to further validate simulation data on the first iteration of the SAFFIRE flight weight engine and predict which future development paths involving the cooling method of the engine (to allow a stable operating temperature of the engine) and the feed cycle (which is responsible for supplying the propellants to the rocket engine) ASRI can consider based on the increases in the payload predictions each engine configuration offered.

He presented his research at the 2023 AeSSA conference in Pretoria and 2024 AIAA SciTech conference.

During his master’s, Silver was able to pace his research to enjoy his studies alongside sports and hobbies that he enjoys, making for a positive work-life balance. He will continue working as an engineer with ASRI, developing on-orbit thrusters for satellites and space crafts.

He thanked his parents for their unwavering love, support and sacrifices; his girlfriend for her love, encouragement and support; and his colleagues at ASRI for making his experience at the institute enjoyable.

Harrylal, who has a Medical degree from UKZN, dreamt of becoming a mechanical engineer because of the promise of bringing science to life to solve real-world problems practically.

Her master’s research involved designing a cold gas roll control system to mitigate vehicle instability during suborbital flight. ASRI is designing suborbital rockets and commercial launch vehicles for satellite deployment that must be controlled. Harrylal’s research formed a first step towards achieving the goal of controlled rocket flight.

Harrylal was also able to present her research at an AeSSA conference and worked part-time while completing her master’s to fund her studies. She also assisted with many ASRI campaigns and programmes during her studies. She now works as an engineer at the institute, conducting research and investigating vehicle flight dynamics, aerodynamics and biomedical devices. She finds her work rewarding as she can apply what she learnt in her undergraduate and master’s studies and see her designs come to life.

Harrylal thanked her family for their support and strength through many challenges.

ASRI Director, Professor Michael Brooks, said the institute was incredibly proud of the three new graduates of ASRI’s Talent Pipeline Programme, funded by the DSI. ‘Each dynamic young engineer brings phenomenal talent and energy to ASRI’s rocket propulsion programme.

‘ASRI produces world-class engineers who can compete with the very best from any country. Thabang, Jordan, Sarisha and all our current postgraduate students are putting South Africa on the global space propulsion map – these are outstanding young aerospace engineers, and we’re producing them right here at UKZN with the strong backing of the University and the visionary support of the DSI,’ he said.

Words: Christine Cuénod

Photographs: Sethu Dlamini and supplied