TAMEST Member Profile: Elaine Oran, Ph.D. (NAE), Texas A&M University

TAMEST Member Elaine Oran, Ph.D. (NAE), Texas A&M University (TAMU), was recruited to Texas from Maryland in 2019 as a Professor of Aerospace Engineering and O’Donnell Foundation Chair IV, with the promise of creating an enormous explosion testing facility on TAMU’s RELLIS campus.

She is a physical scientist and considered a world authority on numerical methods for large-scale simulation of physical systems. An early adopter of computers, she says she has never seen an equation she hasn’t wanted to solve. This drive for understanding has led to a varied research path, including over 40 years at the Naval Research Laboratory (NRL) in Washington before transitioning into an academic research position at the University of Maryland. 

Her research interests include work on chemically reactive flows, turbulence, numerical analysis, high-performance computing and parallel architectures, shocks and shock interactions, rarefied gases, and microfluidics, with applications to combustion, propulsion, and micro-sensor design, astrophysical explosions, and especially to safety.

Though the pandemic has delayed construction on her laboratory for several years, that hasn’t stopped Dr. Oran from continuing her groundbreaking research. In 2020, she helped to discover the structure of “blue whirls,” small spinning blue flames that produce no soot when they burn, and which unleashed a potential avenue for low-emission combustion. 

TAMEST connected with Dr. Oran to learn how her methods unify concepts from science, physics, mathematics, engineering and computer science to form a new methodology.

Please tell us a little about yourself and your work.

I was born in Rome, Georgia, just after World War II, where my father was recovering in a hospital from war injuries. He was in the United States Army Medical Corps in the Pacific and was seriously injured. He primarily practiced dentistry, but also specialized in surgery.

My mother was from a poor family and was extremely talented and self-reliant. She put herself through nursing school and got a degree in anesthesiology after leaving home when she was 16. My parents married late, just before World War II, and at that point, my mother gave it all up to help my father in his offices and to raise her children. Unfortunately, she passed away when I was just 18 years-old and in college.

I was a child of Sputnik. I was reading only Science Fiction stories even before Sputnik. At the time, I lived in a fantasy – I didn’t know that we were not flying around in spaceships and using laser guns. I seemed to be very isolated, and generally we did not have access to all the news and information media we have now. Then Sputnik happened, and I heard about it and went into shock. I’ll never forget that day when the newspaper account caught up with me. I followed my interests and got a Bachelor’s degree at Bryn Mawr College in Chemistry and Physics. That’s where I learned about computers in the early 1960s, which was very early for computers. After Bryn Mawr, I went for a Master’s in Physics and a PH.D. in Engineering and Applied Sciences at Yale University.

After finishing school, my husband and I went to Washington, D.C., where my husband had a job. I worked at the Naval Research Laboratory (NRL) in Washington and was there for over 40 years. After retiring from NRL, I transitioned to University of Maryland, where I stayed until I was recruited to Texas A&M University in 2019.

Now I have many good friends here and live in a beautiful place. Oh, and we have our first truck and a Texas-sized dog.

You are considered a world authority on numerical methods for large-scale simulation of physical systems; how did you find this field of research and what does it mean to you?

When I first came to NRL, the topic of my thesis, statistical mechanics, was not considered particularly relevant. It had a very small audience in theoretical physics; however, I had a tool that others didn’t have in the 1970’s, one that made me very useful to employers – I could program a computer. Thanks to my undergraduate education, I knew Fortran, a general-purpose programming language especially suited to numerical computations and scientific computing.

In fact, I could program quite a few different, basic languages that hardly even exist now. When I got to NRL, they asked that I start using the computer to solve quite a few different sorts of problems, and this allowed me to detour into a variety of different fields during my years there. I started with laser-matter interactions and atomic physics. I started working on the physics of complex chemical and nuclear interactions in a flowing environment in the Earth’s upper and lower atmosphere, which is how I became very interested in basic fluid dynamics and especially in shock waves. I have studied just about every type of flowing state you can imagine, all using theory and numerical analysis, newly developed numerical algorithms, and basic knowledge of math and physics. I especially appreciated the complexity of combustion in terrestrial and astrophysical systems. They are surprisingly related, and they are all relevant for safety considerations here on Earth.

Looking back, I’ve had to do some things that were scary and amazing, and not all related to the computations themselves. One was defining Computational Physics for the American Physical Society, just as we were establishing a new Division on this topic. On another occasion, I was charged to define Aerospace Engineering for the National Academy. A truly frightening task. I’ve been able to interact with amazingly brilliant and kind people along the way.

What makes you the most passionate about your work?

What makes me most passionate is when I understand something that I didn’t understand before, and that perhaps no one understood before. I love knowing an answer in all of its depth and complexity, understanding its application and where it is going, and being able to see a very broad context for basic discoveries.

I get excited when I learn something so basic or fundamental about how a system is working, that the knowledge is immediately absorbed and goes everywhere, becomes part of the “lore,” and then is used in safety or design applications, without even knowing where it came from. That’s happened to me several times, and it is very exciting.

What brought you to Texas and why have you stayed?

I was at the University of Maryland and someone from Texas A&M University called and asked if I would be interested in a faculty position there.  At first, I didn’t really think I was, but my husband said, “Why didn’t you ask for something big that you really want?”

So, I asked for an experimental facility, a large tube for studying detonations and deflagration-to-detonation transition (DDT), one that was bigger than we had before. One that would allow to delve into some very fundamental questions in reactive flows, such as DDT and detonation limits. These were questions that I could only speculate on before. Our previous laboratory in Lake Lynn, Pennsylvania, and operated by NIOSH, had been closed some years earlier, and I thought it would be important to have something like that again, but on a larger scale. A facility that would continue to produce the challenging results and trends we previously found.

So, I called back and asked, “Would you be willing to build this?” They said “yes” before I finished the “pitch,” and that’s what happened. That is the origin of the Detonation Research Tube Facility (DRTF), now being constructed at the Rellis Campus. 

Unfortunately, because of COVID-19, that is, the effective hibernation and the larger concerns for health and safety, plans for building the DRTF were stalled until recently. Now the project has started to move forward again. It will be an enormous explosion testing facility, with the main tube 150 m long, 2 m wide, and emptying into a large “muffler” the size of a football field. The possibility of the DRTF was a strong incentive to stay and see what would happen. I’m really excited about our new potential to investigate some of the biggest, most fundamental problems in reactive flows and some of the biggest safety problems in hydrocarbon production, storage and transport, mine and grain storage explosions, hydrogen use and safety, and so much more.

In 2020, you helped to discover the structure of “blue whirls,” small spinning blue flames that produce almost no soot when they burn. How did you make this discovery?

Fire whirls can be thought of as tornadoes, enhanced and driven by fire, and therefore containing flames and ash. They can be very scary and uncontrollable, and they are a dominant feature when they occur in wildland fires. They are so much larger and more powerful than the fire around them. A firefighter can only run away or clear the land around the fire whirl and hope it will run out of fuel and die.

Fire whirls can range in size from centimeters to kilometers, and the large ones in wildland fires can throw burning material that will land kilometers away and cause more fires. This is another, very dynamic way the worst fires are spread. What we learned is that fire-whirl burning is cleaner because it is hotter and so more efficient at burning up pollutants and debris.

When we saw a video of fire whirls burning a distillery’s spilled bourbon on a pond, we began testing fire whirls burning hydrocarbons on water to see if they might be used beneficially for oil-spill remediation. We were creating relatively small, 1-meter-high fire whirls in a fire laboratory.

Then, not far into the project, we saw a fire whirl self-intensifying, appearing to spin faster and faster, and at one point it started to change completely. It changed over a period of seconds from a very noisy, turbulent 1-m-high fire whirl into a tiny little blue flame that was a couple of centimeters high, quiet, and laminar. It was just spinning, looking like a perfect top, entirely blue, and it meticulously moved around to devour all remaining fuel. When it had finished burning it all, the blue flame became very small and died out. If we gave it more fuel it kept burning until there was no fuel available. It just cleaned the water. We tested burning everything from large hydrocarbons to gasoline to diesel fuel – even rye whiskey. Later in the laboratory, extensive experiments measured many properties of this flame. The pictures and videos were spectacular, in fact worthy of an art gallery.

Later we learned that a blue whirl did not have to be created by burning hydrocarbons on a water surface. For example, a smooth metal surface works, or we can even vaporize the fuel and put it through a burner, and if the conditions are right, we can still create a blue whirl. The three-dimensional unsteady numerical simulations of the blue whirl were very difficult and costly to do, but they were necessary to confirm the flame structure and some of the dynamic properties. Finding the blue whirl was serendipity, but it did arise from being able to explore the idea that a couple of my colleagues and I had for using fire whirls for oil-spill remediation.

What is the next step in this research? Talk about this new potential avenue for low-emission combustion.

There are at least two directions it can go. One intriguing issue is this:  How do you make it bigger? Does it scale? I have students working on this now, but it is expensive to do these calculations on the larger systems. And such calculations should be carried out before any large-scale blue-whirl experiments are attempted anywhere. We might learn, for example, that it is quite feasible and beneficial to use the blue whirl for a combustor on a low-gravity extraterrestrial body.

Now the original idea, using fire whirls for oil-spill remediation, is a concept that the Bureau of Safety and Environmental Enforcement (BSEE) is testing.  There will be some relatively large and exciting experiments at TAMU this spring.

What are you the proudest of about your work and career?

There are many things that make me smile and feel good. Some are relatively small and only affect me in some, perhaps even secret way. Others have had more important, even more global effects and are well published. Let me mention a few.

First, there is a scientific research topic totally different from the blue whirl, but still an amazing flow transition. It is called the deflagration-to-detonation transition, or DDT.  This is a process of events through which a chemical or nuclear reacting system very suddenly makes a transition from turbulent burning (a deflagration) to a detonation. This is a transition that changes the state of the reactive-flow system from a subsonic flow to a supersonic shock-driven flow. In some cases, DDT is extremely dangerous and to be avoided, especially when it is related to maintaining safety in handling fuels. For example, DDT events in vapor-cloud explosions have caused some of the deadliest explosions in fuel storage plants. Now, however, DDT and the subsequent formation of a propagating detonation are now being developed for high-speed detonation-based engines. And finally, DDT is the way astrophysical bodies, such as supernovae, explode. The product of these explosions are the many chemical elements critical to our lives and technologies.

My work on DDT started in the 1990’s and is ongoing. Thanks to many brilliant colleagues and the more advanced computational tools we have now, we are learning the mechanisms underlying this flow transition. In fact, I believe that now we are close to a critical understanding of how and when this transition occurs. Once we know and can control this for common fuels, we will know how to accelerate it, which will help the various engine applications. Or we may understand how to stop it completely, which is important for safety. All of this has implications for astrophysics if we can use the information to understand how stars ignite and explode and form elements necessary for life and the world we live in.

Another thing I’m proud of, and that is amusing, is the development of what is now called “reactive flow” as an area critical to many engineering and scientific fields. As I remember, a colleague and I and came up with this term in the 1980’s when we were trying to replace the word “combustion” with a phrase that expresses the dynamics of the interactions of chemical or nuclear energy changes and fluid dynamics. Now it is used frequently and there are even jobs advertised for specialists in this field.

Finally, I am so proud of my students and colleagues. A list of their names would entirely fill this interview. I’ve worked with people from all over the world who have made major contributions to research or administration or industry, both in the United States and abroad. It is wonderful to learn that a former student or colleague is recognized for doing something amazing.

What do you like to do outside of work?

I read anything that is in front of me. I like walking and bird watching. I love diving. I like to travel a lot. I even love to be on an airplane, especially the take offs.

I like photography, love doodling, sitting and staring at the lake outside of my house in College Station, trying to grow plants, watching movies, drinking wine and Scotch, and talking to friends.

What does being a member of TAMEST mean to you?

It took a while to move to College Station in 2019 because there was so much sorting out and traveling to do before I could come and see where I was. When I learned I was a member of TAMEST, I was encouraged to participate and thought it looked like a wonderful organization.

Soon after I had settled in, COVID-19 hit, and I was unable to participate because we all went into hibernation. Now, however, I look forward to attending conferences and moving forward.

I’m excited to meet other TAMEST members, and I will be more involved now that COVID-19 appears to be more under control.

Is there anything else you’d like to add?

Everything here that I talked about – the things I like to do and the things I’ve discovered – are only possible because of my husband, Dan. He has agreed, encouraged, and even instigated our coming to Texas. I probably would have said “no” to moving here because it would be such a big change, but he encouraged me to ask for something important and reminded me that our family is scattered across the country, and we can all fly to see each other whenever we want. He’s really been a major force and an inspiration in my life.

In addition to Dan, I’ve had a couple of amazing mentors. There are two names I want to mention in particular.

One person is Jay Boris, who taught me what computational physics is, and with whom I worked with for at least 30 years at the Naval Research Laboratory (NRL). We wrote the book together, Numerical Simulation of Reactive Flow, which was reprinted and translated into too many languages to name.

The other was Yvonne Brill, an amazing woman who died in 2013. She was a famous rocket scientist and inventor, almost 20 years my senior, who took me on as one of her protégés. Yvonne was a person of force, with high principles, and strong determination. When she called me to give me orders, and this was almost always to help someone else, my husband, Dan, would always say, “The general is on the phone.” I am very, very proud now to have known and worked on so many projects with her. For inspiration, I highly recommend looking her up.