Profiles in CFD: Maximilian Maigler

The Profiles in CFD series aims to provide insights into the latest trends and projects in computational fluid dynamics (CFD) by interviewing CFD personalities from different career paths and levels.

Our guest for today's interview is Maximilian Maigler, a PhD student at Universität der Bundeswehr München. Maximilian's recent success in winning the best presentation at CadenceLIVE Europe 2022 for his work on “Predicting Reentry Trajectories into the Atmosphere of Mars” has garnered considerable attention. The study's numerical modeling, chemistry modeling, and simulations are well worth exploring through the recorded video or the tech brief.

Can you tell us about yourself, your educational background, and how you got started in the field of CFD?

I’m a PhD student at the Bundeswehr University Munich. I received my bachelor’s degree in mechanical engineering from RWU Ravensburg-Weingarten and my master’s degree in CFD from Cranfield University. Currently, I’m doing my PhD in plasma physics and rarefied fluid dynamics, applied to optimizing electric satellite propulsion systems such as ion thrusters. I started with CFD during my bachelor’s degree, where I optimized the injection process of tungsten powder into a supersonic jet for thermal spraying. I immediately fell in love with CFD upon discovering its vast potential.

What project(s) or paper(s) are you currently working on?

My team and I have submitted a paper on a framework for accurately predicting the aerodynamic coefficients of complex 3D geometries for hypersonic reentry into Mars atmosphere in both the rarefied and continuous regimes. I’m also finishing two papers on plasma dynamics in a radio-frequency ion thruster and its testing in a vacuum facility. As a work in progress, I’m collaborating with SLAC to write two papers about ultrafast laser-matter interaction.

Temperature Contours from the Mars Reentry Trajectory study carried out by Maximilian.

Can you share an example of a particularly innovative project you've worked on and what made it successful?

My long-term PhD project is the holistic simulation of the entire gas interaction of an ion thruster, which has not been done before, as per my knowledge. The novelty is that it includes the radio-frequency fields of the electromagnetic fields, gas-surface interaction, ionization of the propellant in the discharge chamber, and the extraction through the grids. With this 3D time-resolved model, though computationally expensive, you can have a detailed look into what really goes on inside those thrusters as well as in the exhaust plume, which is critical for mission planning and performance and the lifetime estimation of those devices.

What are your thoughts on the use of artificial intelligence (AI) in CFD?

AI is a hot topic today, and I hope the pace of new developments keeps increasing. However, the turbulent nature of fluid dynamics, sensitivity to different operating conditions (for example, inlet velocity or pressure), and geometrical diversity make it hard to create reliable large datasets in 3D for machine learning and AI.

A few years from now, do you think AI in CFD could replace experimentation or wind tunnel testing?

I can imagine supersonic and hypersonic wind tunnels being replaced by AI one day. On one hand, that is due to the cost of operating these facilities, and on the other hand, in those regimes, turbulence does not play the same big role compared to incompressible flows, where boundary layer separation is largely due to viscous effects. In supersonic and hypersonic flows, shock-induced separation such as buffeting and a large portion of aerodynamic lift and drag are governed by shocks around the object, which are surprisingly much easier to compute than highly turbulent chaotic flows.

Can you suggest a few must-reads for CFD enthusiasts?

I recommend beginners and CFD experts read the recently published book “A New Hypothesis on the Anisotropic Reynolds Stress Tensor for Turbulent Flows” by Dr. Laszlo Konoszy. He’s one of the leading experts in turbulence research, and the book provides a detailed, mathematical, and physical introduction to the world of turbulence.

What would you be doing if you weren't in CFD?

I would’ve probably become a programmer of some sort of numerics but would still end up working on something in CFD.

Maximilian presenting at CadenceLIVE Europe 2022.

What does your typical weekend look like, or what is your weekend getaway?

Checking the simulations I submitted during the week, playing piano, and, of course, working out at our university’s gym.

What are your golden words for those looking to make a career in CFD?

It’s tough to get acquainted with everything that comes together, like mathematics, programming, meshing, physics, etc. But for me, CFD is one of the coolest things we can do as engineers, scientists, or even designers. So don’t give up; eventually, you’ll find your path in the wide world of CFD. If I could advise someone looking to make a career, I would suggest supersonic or hypersonic external aerodynamics—a hot topic nowadays with lots of applications in the future, such as hypersonic commercial travel!

To read the Technical Brief 'Simulating Reentry Trajectories into the Mars Atmosphere,' based on the study carried out by Maximilian Maigler, click the button below-