This latter work, and his team, were recognized by another highly prestigious technical merit award through Combustion and Fuel Technical Committee of the American Institute of Aeronautics and Astronautics (AIAA). He was the first to demonstrate quantitatively that the shear layer of the liquid propellants injected into thermodynamic supercritical condition grows and spreads similar to incompressible but variable-density gaseous mixing layers. This was shown through jet's initial shear layer growth rate measurements and fractal analysis. Dr. Chehroudi's seminal work implies that atomization theories based upon Rayleigh-Taylor instabilities are no longer applicable to supercritical situation where there is no longer a surface tension; instead, the fluid behavior is determined by turbulence and diffusional mixing (see Dr Josette Bellan). In a recent book titled "Droplet Dynamics Under Extreme Ambient Conditions" edited by Schulte, K., Tropea, C., and Weigand, B, 2022, and in a paper titled "Modeling and Simulation of a Turbulent Multi-component Two-phase Flow Involving Phase Change Processes Under Supercritical Conditions," the authors (Kuetemeier, D. and Sadiki, A.) from Technische Universitat Darmstadt wrote "For the model validation in this class of investigations the detailed study by Chehroudi, who neatly generated and compared various experimental data from different liquid and gas jets as function of pressures, remains state of the art." His Invited Review article on this subject is titled "Recent Experimental Efforts on High-Pressure Supercritical Injection for Liquid Rockets and Their Implications". Dr. Chehroudi's newly-proposed combustion instability theory for liquid rocket engines is yet another unique contributions recognized by his peers as innovative and highly creative.
His work also expanded into frontiers of nanotechnology by pioneering the only nanotechnology-based light-activated volumetrically-distributed ignition system for both automotive (HCCI) and rocket engine applications. His creative /original idea and the R&D work directed by him, delivered an elegant answer to a technological barrier referred to as "controlled autoignition", being at the heart of the next generation advanced HCCI engines. His imagination, initiative, leadership, and technical vision in this area have, not only set the stage and the R&D roadmap for new applications of nanotechnology in volumetrically-distributed fuel/propellant photo ignition for the first time in literature with subsequent followers, but also convinced program managers at AFOSR in creating a fully-funded five year program for this research work while at AFRL. Subsequent nanotech-based photo ignition efforts at AFRL were guided by his strategic plan, visionary thinking, and original imaginations. His work on synergy between supercritical fluids and nanotechnology can be found in an invited review article titled Supercritical Fluids: Nanotechnology and Select Emerging Applications.
Dr Chehroudi's past research projects had contributions and impacts in a number of areas. First, on account of the multidisciplinary nature of most efforts, they enhanced inter- and intra-organizational communication and created synergistic joint efforts. Second, many of them led to fundamental understanding of the underlying physics of the problem. Third, they substantially enriched the visibility and scientific credibility of the division. Fourth, they led into tremendous performance improvement on the existing products and led to either new products/technologies or product ideas. Fifth, many of them won technical merit awards from prestigious scientific/engineering societies (listed in the AWARDS section). Sixth, sustained award-winning high-quality publications and reports with useful results which encouraged continued support by funding agencies.
Dr. Chehroudi has a PhD in Mechanical & Aerospace Engineering and Post-Doctoral Fellow (Princeton University), MS in Mechanical Engineering (Southern Methodist University, Summa Cum Laude), MS in Economics (Swiss Finance Institute, Magna Cum Laude), and BS in Mechanical Engineering (Sharif University of Technology, top 5%). He is a senior member of the American Institute of Aeronautics and Astronautics' Propellant & Combustion (P&C) Committee (2008-present) and was honored an Associate Fellow title from the American Institute of Aeronautics and Astronautics (AIAA.org). The P&C Committee focuses on physics and chemistry of reactants and working fluids for reaction propulsion, including properties of propellants, aerothermodynamics processes, and thermal energy conversion.
Throughout years, Dr. Chehroudi has evolved into a leader who forms synergy, cultivates a culture of innovation and collaboration, communicates unambiguously and respectfully, builds trust and consensus, injects motivation and inspiration, and guides/encourages strategic/systemic thinking. These incipient talents are those he has nurtured through interactions with colleagues/mentors which have been critical and precious elements facilitating stellar achievements from his teams. Moreover, he brings extensive level of technical leadership and presentation skills (to technical/nontechnical, ( C-level, & clients) in a broad range of disciplines/technologies, which are instrumental in leading multidisciplinary teams, in technology development, forecasting and transfer, as well as in revenue-generating new product development (NPD) and R&D efforts. Lastly, when a solid educational background (PhD/MS/BS in Mechanical/Aerospace Engineering and MS in Economics/Management) is added to the mix, the package as a whole creates a multidimensional professional who understands and quickly grasps the importance and potential of research/development activities for commercialization in a wide range of science, technology, and engineering fields and who markets such opportunities and ideas towards goals/objectives of the organization.
He acts as a reviewer for many scientific and engineering journals and publishers, has been a Technical Editorial Director of the Powertrain International, Editorial Board of the Journal of Combustion by Wiley’s Forward Series, and has delivered over 200 presentations in technical meetings/conferences (SAE, AIAA, ASME, Professional Education Seminars, etc) and to nontechnical audiences and has over 20 technical reports (Princeton University, General Motors, Ford Motor Co, Department of Energy, NASA, Air Force Research Laboratory).
He has also produced five 600-plus-page monographs on combustion and emission of pollutants from mobile power plants, ignition technologies, liquid fuel/material injection, and nanotechnology, two book chapters on liquid propellants and combustion instability(*) and applications of graphene (a nanotech product) in ignition and combustion of fuels/propellants, ground-breaking patents on applications and synergy between nanotechnology, light, and chemical reaction for a light-activated volumetrically-distributed ignition of fuel-air mixtures and liquid fuel sprays with applications in Low Temperature Gasoline Combustion (LTGC) or HCCI, and liquid rocket engines.
Dr. Chehroudi has more than 150 publications with extensive experience in both scientific and management areas and intensive trainings in finance and financial engineering. His time-tested innovative contributions will continue (as it has) no matter what he does or which organization he will be affiliated.
(*) The Encyclopedia of Aerospace Engineering represents a major publishing initiative by John Wiley and Sons Inc., to establish a high quality, carefully coordinated reference work that will enhance education, training and research in this complex and demanding field.
