Propulsion, Combustion, and Detonation at Texas A&M’s Turbo Lab

Texas A&M’s Turbomachinery Laboratory has been an industry hub of knowledge and new research for decades, cultivating both young and established talent and partnering with major technology developers to address energy/machinery challenges since its inception. With new research topics introduced and facility upgrades underway, the Lab now has more to offer for the industry as a whole.

Turbomachinery International visited the campus last month and had a chance to speak with Dr. Eric Petersen, Professor of Mechanical Engineering and Director of Texas A&M’s Turbo Lab, about the facility’s latest research focuses, trends in propulsion and combustion, and the university’s new addition: the Propulsion and Energetics Research Laboratory (PERL).

TURBO: What new propulsion and combustion research has the lab been working on?

Petersen: New research in these areas covers a range of fundamental and applied topics of interest, such as power generation gas turbines, rocket propulsion systems, explosion and detonation safety limits, aviation jet propulsion, advanced optical diagnostics, and related research for hypersonic propulsion systems. Some specific topics include emission spectra measurements, ignition times, flame speeds, and species concentrations to understand better the combustion chemistry of ammonia and related fuel blends.

We’re also characterizing the explosion limits and reactivity of cryogenic rocket propellants, combustion chemistry of lithium-ion battery fires and fire suppressants, femtosecond laser-based diagnostics, and shock propagation in energetic materials, among others. In recent years, we’ve been developing methods for studying coke formation and possible ignition in lubrication oils when exposed to elevated temperatures.

TURBO: Now that PERL is complete, how has it allowed you to expand and perform experiments at higher pressures and flow rates?

Petersen: The new laboratory building is finished but is just now opening, so we haven’t used it for testing yet. We are excited about this new opportunity, which will make safe, high-pressure, and high-energy experiments possible for the core Turbo Lab faculty and other researchers at Texas A&M. We will also make the facility available for external users. We think this resource will be useful for smaller companies that do not have such capabilities, as well as for larger companies that would like to use a facility that offers quick turnaround, lower overhead expenses, and ready access to the expertise of the various professors.

Rendering of the Turbo Lab with PERL facility; image credit: Texas A&M Engineering Experiment Station

TURBO: What about chemically reacting, high-pressure, high-temperature flow experiments?

Petersen: The PERL is configured to allow high-pressure, reacting flows in both open and closed configurations for propulsion and gas turbine applications and dynamic events such as detonations and explosions. While we have conducted related testing in our Turbo Lab facility for several years now, the PERL will allow for a scaling up in terms of both the test article size (higher flow, larger size, higher pressure, etc.) and the number of ongoing projects being conducted simultaneously.

For example, we could operate small rocket motors or detonation-propulsion systems where the nozzle exhausts into open air. Of course, every test cell can be isolated so that no personnel are near the experiment while running, as there are two separate control rooms built into the facility. We also have an isolated room for housing expensive optical diagnostics and lasers, with built-in optical access to every test cell.

TURBO: What are your goals for the new lab?

Petersen: Our near-term goal is to instrument the facility control rooms and bring local experiments into the test cells to immediately take advantage of this new resource and demonstrate its full capabilities. The long-term goal is to obtain enough local research through traditional pathways that faculty members can utilize to fund their research (government and industry grants and projects). We’ll also bring in outside users to make the PERL self-sustaining in terms of its operational expenses. Fees from renting out PERL test cells will maintain the building and support staff and day-to-day operations.

TURBO: What trends are you seeing in combustion and propulsion?

Petersen: There is much interest and research activity in all things related to hypersonics, which includes advanced propulsion systems with air-breathing, solid-fueled, solid-propellant, or detonation-based systems. Related research ranges from applied testing to understanding the fundamental physics and chemistry of a combination of solid, liquid, and gases within reacting, high-speed flows. The relevant conditions involve high temperatures, high-velocity flows containing shock and expansion waves, high pressures, and heterogeneous combustion—making the PERL a resource for conducting research under these conditions.

TURBO: Is there anything you want to highlight from a program or research standpoint?

Petersen: The Turbomachinery Laboratory research center involves over a dozen core faculty from mechanical, aerospace, and chemical engineering at Texas A&M. People who are interested in learning more about our research, partnering with our affiliated faculty members, or hiring one of our in-demand graduate students, please visit our website.

Stay tuned for more exclusive interviews, video conversations, and our full writeup on our visit to Texas A&M's Turbomachinery Laboratory.