Dr Maciej Grybko – a PhD candidate at the University of Southern Queensland. A graduate of engineering studies at the University of Leeds and master’s studies at the Illinois Institute of Technology in the field of aerospace engineering. His doctoral thesis focuses on the construction of a rotating detonation engine in a jet configuration and its testing in a hypersonic wind tunnel. Maciej has built several high-power amateur rockets and a solid-fuel rocket engine. He founded two student rocket clubs, Illinois Tech Rocketry and UniSQ Student Rocketry, which compete in the most prestigious rocket competitions in the world. Maciej’s goal is to radically reduce the costs of space flights by utilizing his rotating detonation engine.
The article is part of a series of Coopercnius conversations with Polish scientists with foreign scientific backgrounds.
Early Academic Path
My journey with science began seriously in high school. When I was choosing a high school, an innovative teaching program opened up at XX High School in Gdańsk. Coincidentally, it was the closest school. This program, colloquially called super-math-physics, focused heavily on teaching mathematics, physics, computer science, and English. As part of this program, I took mathematics exams at the Gdańsk University of Technology, attended science camps, and participated in competitions. In reality, by the end of high school, I completed all the mathematics of engineering studies at Gdańsk University of Technology.
Going abroad was guided by my ambitions. I wanted to study at a prestigious university to learn as much as possible and make connections. Additionally, I wanted to become independent. Unfortunately, the choice of university was off the mark. My knowledge, at least in mathematics, far exceeded the level of studies, and I was simply bored. The university forbade me from attending lectures of higher years, and when I asked what I could get involved in scientific projects, I received the answer “go read something in the library.”
Following Instinct
Before starting my studies, I became interested in Aerospace Engineering. I was passionate about mathematics, but I was looking for its practical application and wanted to achieve something groundbreaking in my career. I didn’t know what it would be yet, but I decided to trust my instincts. First, I became interested in jet engines. I focused on getting an internship after the first year of studies, so for months, I read about manufacturers of these engines. Unfortunately, I got discouraged quickly after failing in the first round of recruitment on some stupid numerical test that had nothing to do with mathematics. And then rockets came to my mind. One of the biggest advantages of being a student is unlimited access to scientific materials, which are normally paid for. So, I downloaded as many books and articles about rockets as possible and read them. At the same time, I attended local conferences where I learned about unconventional space propulsion, met space enthusiasts, and developed my passions. I often traveled to Poland and also participated in space conferences there. The space industry in Poland is relatively small and well-integrated. The same people appeared at every conference, and everyone knew everyone. So when I appeared there as the only student, I was able to make contacts easily. They resulted in an internship at Space Forest – the only Polish company producing rockets. I am immensely grateful for both internships, and I still keep in touch with the experts from Space Forest. It was one of the most important moments in my career. Preparing rockets for flights stimulated my imagination a lot, and then I realized – this is what I want to do in my life.
Scholarship as a Ticket Overseas
I went to the States for my master’s studies. It wouldn’t have been possible without a scholarship organized for me by my mathematics teacher from XX High School. My main goal was to initiate a student rocket club at my university. And although it wasn’t easy, it happened. The club developed incredibly, and a year after my departure, the team qualified for the world’s largest rocket competition – the Spaceport America Cup. I thought that after completing my master’s studies, I would easily get an engineering job in the States. However, that didn’t happen. After six months of job hunting, I went bankrupt and had to return to Poland. There were two reasons. Firstly, ITAR legal regulations in the States protect space knowledge (especially about propulsion), and no space company, e.g., SpaceX, has the right to hire a foreigner. So I couldn’t get a job in my field. Therefore, I was looking for any engineering job to start with. And here came the second problem. Employers told me directly that I was too specialized in rockets. Even when I tried to hide it on my CV, they quickly realized it. And I faced rejection. So I came to the conclusion that there is no turning back now. I have to work on rockets.
My plan B was a PhD. In the States, even a PhD was not possible because of ITAR. However, Australia was very open to cooperation. I applied for a total of three doctoral programs. The first two projects were interesting, albeit more theoretical. For various reasons, they didn’t materialize. I was very interested in experimental work, preferably something related to combustion. I couldn’t hit better. The third project involved building and testing an unconventional propulsion system – a rotating detonation engine in a hypersonic wind tunnel.
I first heard about rotating detonation while reading the works of Professor Piotr Wolański. He was a world-renowned pioneer in detonation research. I met him once at a conference, but I didn’t yet know that I would be dealing strictly with his field. Professor Wolański tried to arrange an internship for me at NASA. He also answered numerous questions I had at the beginning of my PhD. Unfortunately, he passed away last year. I am currently halfway through my PhD. I have to admit, I’m just crawling in my field. I don’t have any publications yet, but I have many ideas and plans for many years. This month is full of experiments. I just finished hydrogen detonation experiments, and after the weekend, I will start another set of experiments – characterizing the flow of our hypersonic wind tunnel. I recently sent my rotating detonation engine prototype for production. I plan to start testing it in August. The goal of my PhD is to achieve a rotating detonation and investigate the influence of various parameters on the behavior of this detonation. After my PhD, I would like to continue my research on the engine. I dream of testing this engine in real flight.
Why Do I Believe My Research Is Important? The rotating detonation engine is much more efficient than conventional engines (the reaction itself is 20-30% more efficient). Additionally, it is much simpler to build – it has no moving parts. Because the detonation occurs very quickly and over a short distance, this engine can be much smaller and lighter – it will offer less resistance during flight. I see two applications for this engine. Firstly, supersonic passenger flights. So far, they have not been possible, or rather profitable (e.g., the Concord aircraft), because traditional jet engines create enormous resistance and dramatically lose efficiency after breaking the sound barrier. Initial studies of rotating detonation jet engines show that they maintain their efficiency over a wide range of supersonic speeds, which could enable such flights at reasonable prices. Secondly, space flights. Every gram counts in space flights. Increasing the efficiency of engines will allow much heavier payloads to be sent into space. Or, looking at it from another perspective, much smaller rockets will be needed to carry the same payload, a much smaller rocket would be sufficient. Additionally, the simplified construction would further reduce flight costs. I believe that this technology will decrease the cost of space flights tenfold. Opening up affordable access to space would change our world beyond recognition.
Testing such engines is a huge challenge. In order to create conditions in our aerodynamic tunnel corresponding to flight at Mach 4, we need to heat the tunnel to its limits. One of the biggest limitations is today’s materials. Supersonic flights generate temperatures on the order of thousands of degrees Celsius. That’s why the development of material technology and 3D printing is so important. For example, 3D printing allows for the production of the entire engine as one unit with cooling channels that couldn’t be hollowed out using traditional methods.
In conclusion, I believe that in the development of a young scientist, curiosity and patience are the most important. Curiosity is the key to great discoveries and, most importantly, allowed me to discover exactly what I want to do in life. It’s worth engaging in various interests, exploring them, and evolving over time. Meanwhile, patience is essential for achieving our dreams. In high school, I thought that perseverance and ambition would lead me to success. Now I have a completely different opinion. I believe that a healthy routine, caring for both scientific and personal development, and deriving joy from the daily work itself, not just the achievements, are most important.”
Fot. Unsplash
