AFOSR - Engineering and Complex Systems


The Engineering and Complex Systems team within the Engineering and Information Science Branch leads the discovery and development of the fundamental and integrated science that advances future air and space flight. The broad goal of the team is to discover and exploit the critical fundamental science and knowledge that will shape the future of aerospace sciences. A key emphasis is the establishment of the foundations necessary to advance the integration or convergence of the scientific disciplines critical to maintaining technological superiority.

A wide range of fundamental research addressing electronics, fluid dynamics, materials, propulsion, and structural mechanics are brought together in an effort to increase performance and achieve unprecedented operational capability. The team carries out its ambitious mission through leadership of an international, highly diverse and multidisciplinary research community to discover, shape, and champion new scientific discoveries that will ensure novel innovations for the future U.S. Air Force.

The central research direction for this team focuses on meeting the basic research challenges related to future air and space flight by leading the discovery and development of fundamental science and engineering in the following research areas.

The Engineering and Complex Systems (AFOSR/RTA1) Program Officers and topics are:

  • Dynamic Materials and Interactions
  • GHz-THz Electronics and Materials
  • Energy, Combustion, and Non-Equilibrium Thermodynamics
  • Unsteady Aerodynamics and Turbulent Flows
  • High-Speed Aerodynamics
  • Aerospace Composite Materials
  • Multiscale Structural Mechanics and Prognosis
  • Space Propulsion and Power
  • Agile Test Science for Test and Evaluation

Our research areas of interest are described in detail below:

Dynamic Materials and Interactions

Program Description: The objective of this portfolio is to develop the fundamental scientific knowledge required to understand the dynamics of complex, heterogeneous and reactive materials for game-changing advancements in munitions and propulsion. The research areas supported by this portfolio therefore seek to discover, characterize, and reliably predict the fundamental chemistry, physics, hydrodynamics and materials science associated with the high energetics of explosives, solid propellant burning, and structural dynamics of materials subject to shock loading. The overall scope of the research in the portfolio will be accomplished through a balanced mixture of experimental, numerical, and theoretical efforts. The fundamental science of interest to this portfolio is necessary for revolutionary advances in future Air Force weapon systems and their propulsion capabilities, including increased energy density, operational efficiency, effect-based optimization, and survivability in harsh environments.

Basic Research Objectives: Research proposals are sought in all aspects of the chemistry and physics of energetic materials with particular emphasis on chemistry-microstructure relationships and the fundamental dynamics of heterogeneous materials with complex structural properties. The problems of interest span multiple time and length scales, and strongly couple a broad range of physical phenomena, presenting fundamental challenges in experimental characterization, data assimilation, and model development. Efforts that leverage recent breakthroughs in other scientific disciplines to foster rapid research advancements are also encouraged.

Topics of interest include, but are not limited to, the following:

  • New diagnostics for measuring the shape and speed of reaction fronts within well-characterized samples subject to various loading conditions. Ideally, this would require micro-meter and nano-second spatial and temporal resolution respectively. In addition, reliable transient pressure and temperature measurement during dynamic loading conditions would be invaluable, especially when conducted at high resolutions.
  • Mesoscale experiments to understand the initiation of energetic materials (explosives) or reactive properties of solid propellants, including shock-loading and mechanical response of energetic crystals.
  • Shock wave and detonation physics, including the quasi-steady and unsteady reacting front propagation, non-equilibrium effects, stability characterization, shock response of polymers, composites, and geological materials.
  • Prediction of processing, structure, and property relationships in energetic materials, including reactive materials by design, and the ability to tailor stress waves and shock shapes from first principles, as an inverse design problem via microstructural and chemical properties.
  • Novel, high energy density material compositions that overcome the CHNO limitations, including scale-up techniques required for gram-scale production and characterization
  • Advanced mathematical and numerical techniques for multi-physics and multi-scale modeling and simulation (M&S) in energetic and other heterogeneous materials, aimed at developing new capabilities for numerical prediction of future munition technologies and their effects.

You are highly encouraged to contact our Program Officer prior to developing a full proposal to briefly discuss the current state-of-the-art, how your research would advance it, and the approximate cost for a three (3) to five (5) year effort.


GHz-THz Electronics and Materials

Program Description: This program seeks scientific breakthroughs in materials, heterostructures, and devices that can lead to game-changing capabilities in RF sensing and amplification, transmit/receive functions, wideband operation, and novel functionalities. The primary frequencies of interest range from GHz to THz.

Basic Research Objectives: The focus of the portfolio is on understanding and exploiting fundamental interactions of electrons and quasiparticles with each other and their host materials in all regions of device operation. Technical challenges include understanding and controlling (1) interactions between particles/quasiparticles and host lattices, boundaries, and defects, including thermal effects and changes over time that limit lifetime and performance; (2) carrier velocity; and (3) methods of device operation that do not rely solely on conventional transistors or transport mechanisms such as drift, diffusion, and tunneling. Included are carrier transport and properties in regimes in which transport is not limited by scattering mechanisms, such as in topologically protected states. Efficiency, volume, speed, and power are important figures of merit. It is expected that to understand fully the various new phenomena and device configurations, novel techniques to study and control nanoscale structures, defects, and operations may be required. The program emphasizes experiments and also supports theory and modeling.

Proposers are highly encouraged to contact the Program Officer prior to developing a white paper or proposal, preferably by email, to discuss the current state of understanding, how your research would advance it, and the approximate cost of a three- to five-year effort.


Energy, Combustion and Non-Equilibrium Thermodynamics

Program Description: This portfolio addresses energy needs of Air Force aerospace systems for the propulsion and non-propulsive functions of increasingly significant energy requirements. The portfolio emphasizes three foundational elements: (1) Fundamental, (2 )Relevant, and (3) Game-Changing, i.e.: starting from establishing fundamental scientific understanding and quantifying rate-controlling processes, focusing on Air Force interests and relevant conditions, encouraging multi-disciplinary collaborations, interactions and unconventional and innovative thinking, leading to game-changing concepts and predictive capabilities for the Air Force

Basic Research Objectives: Research topics in this portfolio include all energy aspects relevant to Air Force needs, combustion and otherwise, with the following sub-areas:

Fundamental Combustion Understanding in Air Force Relevant Regimes:

Combustion is the primary conversion process to supply energy for propulsion and other functions of aerospace systems such as planes, rockets, hypersonic and UAV systems. In these systems, the fuel combustion process occurs at highly turbulent flow conditions, governed by underlying molecular changes from high-energy states to lower ones, generating usable energy for system functions. The key turbulent combustion attributes are critical in determining operability, performance, size and weight of such systems. The understanding of these key attributes and the quantification of the inherent rate-controlling processes provide the scientific foundation of modeling/simulation capabilities needed for the design of new generations of AF aerospace systems. Based on recent progresses in understanding/modeling key chemical reaction pathways in combusting AF/DOD fuels and in exploring key attributes of turbulent flame structure and dynamics at relevant conditions, the turbulent combustion part of the portfolio currently focuses on exploring, understanding and qualifying the turbulent-chemistry interactions using physical and numerical experiments. This includes but is not limited to:

  • Effects of turbulence on rate-controlling properties/processes of fuel combustion chemistry;
  • Turbulent production by the energy release from combustion chemical reactions;
  • Spatial/temporal scale interactions of turbulence structures and dynamics;
  • Diagnostics for measuring key properties/processes in turbulent combusting flows.

Multi-Physics, Multi-Scale Modeling/Simulation for Energy Conversion:

Energy conversion processes in AF aerospace systems involves coupled multi-physics phenomena such as chemical reactions, turbulence, radiation, flow-material interactions, etc. in a wide range of spatial and temporal scales. Computationally efficient modeling/simulation capabilities with sufficiently low uncertainties, coupled with measured data, and assisted by artificial intelligence and machine learning will have game-changing impacts, potentially resulting in new, intelligent development & design tools for future aerospace systems. Such modeling/simulation capabilities may also be used to select and conduct “numerical experiments” to explore underlying physics at conditions where physical experiments are very difficult or impossible. Key focus areas are the physical foundation and numerical approaches for coupling multiple physical phenomena at different spatial and temporal scales, in particular:

  • Embedded DNS (eDNS) – embedding “direct numerical simulation” (DNS being capable of resolving turbulence scales, down to the dissipative range, and detailed flame structures) into simulations for larger-scales such as large-eddy-simulations (LES) to provide needed resolutions/details in both small and large scales computationally efficiently;
  • Coupling numerical simulations for different physics, e.g. coupling Eulerian fluid computations with Lagrange molecular dynamics calculations to provide information on critical properties needed in the larger-scale fluid calculations;
  • Numerical techniques and algorithms for assimilating measured data into numerical simulations, to reduce the simulation uncertainty and to obtain quantitative information which is otherwise not available through experimental measurements alone.

Game-Changing Thermodynamics Concepts and Innovative Energy Conversion:

Thermodynamics provides insights into energy conversion processes and the foundation to developing potentially game-changing energy-conversion approaches. It also establishes the thermodynamic foundation and framework to analyze the energy requirement and efficiency of propulsion systems and non-propulsive subsystem functions of increasingly significant energy needs. The following topics are of particular interest:

  • Learning-based, intelligent thermodynamics framework for analyzing multi-scale, non-equilibrium physical and chemical processes, potentially leading to unconventional, game-changing energy conversion processes that potentially offer significantly higher than normal efficiency and other favorable attributes;
  • Thermodynamics foundation and energy optimization for information processing systems.
  • Novel, highly efficient approaches to electric propulsion.
  • Other non-thermal, reduced-thermal and hybrid energy conversion processes, possibly of non-equilibrium nature, for future propulsion and subsystems, with particular interest in UAVs and robotic platforms;
  • Combustion at extremely short time-scales, such as detonation-based processes (e.g. as potential game-changing propulsion approaches) and meld exothermic processes (e.g. biologically inspired energy conversion processes for UAV and robotic applications)
  • Multi-functional fuels: (1) endothermic fuels and systems and (2) aviation fuels from new sources with economic and security advantages and related conversion processes;
  • Unconventional formation mechanisms of large and complex carbon-based molecules, compounds and clusters at combustion, thermal or other interesting conditions, relevant to Air Force propulsion, energy and other interests;

Proposers are highly encouraged to contact the Program Officer prior to developing a full proposal, preferably by email, to discuss the current state of understanding, how the research would advance it, the approximate cost for a three-to five-year effort, and if there are any specific submission target dates.


Unsteady Aerodynamics and Turbulent Flows

Program Description: The Unsteady Aerodynamics and Turbulent Flows portfolio supports basic research into the dynamics and control of aerodynamic shear flows including the interactions of these flows with rigid and flexible surfaces in motion. The portfolio is interested in aerodynamic flows arising in both internal and external configurations and extending over a wide range of Reynolds numbers. The portfolio emphasizes the characterization, modeling, prediction, and control of flow instabilities, turbulent flows, and aerodynamic interactions. A focus on the understanding of the fundamental flow physics is motivated by an interest in developing physically-based predictive models and innovative control concepts for these flows.

Basic Research Objectives: Research in this portfolio is motivated, in part, by the fluid-structure interactions, by vortex and shear layer flows, by the aerodynamic performance of novel configurations, and by enduring questions on transitional and turbulent flows. The portfolio maintains an interest in the dynamic interaction between unsteady fluid motion, linear and nonlinear structural deformations, and aerodynamic control effectors for a wide range of flight regimes.

The portfolio seeks to advance fundamental understanding of complex, time- dependent flow interactions by integrating theoretical, numerical, and experimental approaches: studies integrating these elements to improve understanding are strongly encouraged. Flow control studies are expected to involve an approach based on a fundamental insight into the flow dynamics. In cases where that insight may not exist, studies examining fundamental flow physics with a path to enabling control of the flow may be of interest. Flow control efforts integrating modeling, control theory, and advanced sensor and/or actuator technology for application to a flow of interest are encouraged. Note that basic research of the variety typically funded by the portfolio may not yet have a clear transition path to an application, but nevertheless should be relevant to U.S. Air Force interests.

Proposers are highly encouraged to contact the Program Officer prior to developing a full proposal, preferably by email to discuss the current state of the art in his/her area of interest, how the proposed research would advance it, the approximate cost for a three (3) year effort, and if there are any specific submission target dates.


High-Speed Aerodynamics

Program Description: The flow field around a high-speed vehicle strongly influences its size, weight, lift, drag and heating loads. Therefore, research in this area is critical to the U.S. Air Force’s interest in rapid global and regional response and space operations. This portfolio aims to lay the scientific foundation, through discovery, characterization, prediction and control of critical phenomena, for game-changing advancements in our understanding of high-speed, high temperature non- equilibrium flows around flying vehicles. External and internal transitional and turbulent wall-bounded flows are critical to the cadre of problems studied. Such understanding is a pre-requisite to making hypersonic flight routine.

Basic Research Objectives: Proposals are encouraged which leverage recent breakthroughs in other scientific disciplines and foster rapid research advancements in high-speed aerodynamics. It is encouraged that proposed efforts contain a balanced combination of experiments, computations and theoretical efforts. Flight experiments may be sought for obtaining data that cannot be obtained in ground facilities or by state-of-the-art computations. For any experiments proposed, explain how they capture the most sensitive variables for the problem being studied and how they can be used for validation of numerical models. For any numerical efforts explain which the hardest variables to accurately predict are and how the results will be validated with relevant measurements.

Innovative research is sought in all aspects of high Mach number (preferably M>5), high temperature, non-equilibrium flows with particular interest in (not in order of priority):

  • Shock/Boundary Layer, Shock/Shock, and Shock/Separation interactions and unsteadiness for both external surfaces, and at the inlet and isolators for scramjets
  • Turbulence - structure and growth, unsteady flow field characterization, effects of micro/macro particles in free stream, wall roughness, curvature, angle of attack, etc.
  • Transition - Initial value and Eigen value approaches for transition prediction, stability analysis for different modes and multimode transition
  • Diagnostics - to measure both the shock layer and the free stream disturbances
  • Flow-structure interactions at hypervelocity conditions
  • Development of physics-based models for air ro-vibrational-dissociation and ro-vibrational-translational processes that can: 1) be incorporated in CFD solvers without incurring orders of magnitude more time to solve a given problem. Experiments to validate the above models are also sought.
  • Characterization of fundamental processes occurring between non- equilibrium flows and ablative surfaces
  • Characterization of naturally occurring disturbances in the atmosphere at high altitudes
  • Energy transfer mechanisms within high enthalpy flows
  • Identification and characterization of high L/D shapes
  • Flight experiments to realize basic science advancement in any of the above areas might be sought.

Ideas that don’t strictly fall into the categories above, but are germane to high speed aerodynamics, are also welcome. You are highly encouraged to contact our Program Officer prior to developing a full proposal, in any sub-area, to briefly discuss the current state-of-the-art, how your research would advance it, and the approximate cost for a three (3) to four (4) year effort.


Aerospace Composite Materials

Program Description: Reducing the weight of aerospace platforms, while improving robustness and reliability, reduces costs and emissions and increases payload capacity and overall performance. The Aerospace Composite Materials portfolio supports transformative, basic research in materials design and processing to enable weight reductions with concurrent enhancements in performance and function. Such materials can transform the design of future U.S. Air Force aerospace and cyber systems for applications, which include airframes, space vehicles, satellites, and a multitude of load-bearing components and systems. Key scientific areas supported by the program include: materials discovery, processing and characterization; nanotechnology; integrated computational material science and engineering; composite and hybrid materials processing; and interface/interphase science.

Among the routes to achieving game-changing improvements in aerospace composite materials currently emphasized within the program are: (1) materials discovery and processing to increase properties and performance of structural materials, e.g., matrix resins, coatings, and reinforcing fibers and nanoparticulates; (2) multiscale modeling of material degradation mechanisms to improve material life prediction capability and minimize overdesign of load-bearing structures; (3) understanding the impact of nanoscale porosity on mechanical properties and engineering of porous composites; and (4) the creation and interfacial understanding of hybrid structures that combine materials of different classes, scales, and properties to provide synergistic and tailorable performance.

Basic Research Objectives: Proposals are sought that advance our understanding of hierarchical or hybrid materials and our ability to design, model, and fabricate multi- material, multiscale, multifunctional material systems with a high degree of precision and efficiency. Fundamental research targeting composites that evince multifunctionality, such as high strength plus efficient electrical and thermal transport properties and/or adaptively to enable active aerospace structures, is also a keen programinterest. Material classes may be polymeric, ceramic, or metallic.

You are highly encouraged to contact our Program Officer prior to developing a full proposal to briefly discuss the current state-of-the-art, how your research would advance it, and the approximate cost for a three (3) to five (5) year effort, and if there are any specific submission target dates.

We are currently searching/hiring a new Program Officer, but there is a temporary custodian until a new PO is selected. Emails sent to the email address below will go to the temporary custodian:


Multiscale Structural Mechanics and Prognosis

Program Description: This fundamental basic research program addresses the U.S. Air Force needs in the following application areas: 1) New and revolutionary flight structures, 2) Multiscale modeling and prognosis and 3) Structural dynamics under non-stationary conditions and extreme environments. Other game-changing and revolutionary structural mechanics problems relevant to the U.S. Air Force are also of interest.

The structural mechanics program encourages fundamental basic research that will generate understanding, models, analytical tools, numerical codes, and predictive methodologies validated by carefully conducted experiments. The program seeks to establish the fundamental understanding required to design and manufacture new aerospace materials and structures and to predict their performance and integrity based on mechanics principles.

Basic Research Objectives: Fundamental basic research issues for new and revolutionary flight structures include: revolutionary structural concepts and unprecedented flight configurations; hybrid structures of dissimilar materials (metallic, composite, ceramic, etc.) with multi-material joints and/or interfaces under dynamic loads, and extreme environments; controlled-flexibility distributed-actuation smart structures. The predictive analysis and durability prognosis of hybrid-material structures that synergistically combine the best attributes of metals, composites, and ceramics, while avoiding their inherit shortcomings are of great interest.

Fundamental basic research issues of interest for multiscale modeling and prognosis include: physics-based models that quantitatively predict the materials performance and durability of metallic and composite flight structures operating at various regimes; modeling and prediction of the structural flaws distribution and service- induced damage on each aircraft and at fleet level; structural analysis that accounts for variability due to materials, processing, fabrication, maintenance actions, changing mission profiles; novel and revolutionary on-board health monitoring and embedded non-destructive evaluation (NDE) concepts.

Fundamental basic research issues for structural dynamics include: control of dynamic response of extremely flexible nonlinear structures; control of unsteady energy flow in nonlinear structures during various flight conditions; nonlinear dynamics and vibration control of thin-wall structures of functionally graded hybrid materials with internal vascular networks under extreme loading conditions.

You are highly encouraged to contact our Program Officer prior to developing a full proposal to briefly discuss the current state-of-the-art, how your research would advance it, and the approximate cost for a three (3) to five (5) year effort, and if there are any specific submission target dates.


Space Propulsion and Power

Program Description: Research activities are focused as multi-disciplinary, multi- physics, multi-scale approach to complex problems, and fall into four areas: Coupled Material and Plasma Processes far from Equilibrium, Nano-energetics in solid propellant combustion, High Pressure Combustion Dynamics in rocket engines, and structural batteries.

Basic Research Objectives: Research in the first area is to significantly advance the state-of-the-art in our ability to understand the fundamental aspects of a coupled plasma/material system in non-equilibrium states, for a variety of potential applications, including plasma-based space propulsion systems and plasma-spacecraft interactions. The typical conditions of interest are characterized by critical phenomena in small spatial and temporal scales which affect the behavior over a much wider range of scales. Detailed understanding and control of non-equilibrium and multiscale effects have the potential to overcome the limitations of traditional plasma in thermodynamic equilibrium, leading to improved system designs; preventing or leveraging dynamic features such as instabilities, coherent structures, and turbulence; and realizing chemical pathways, structural changes or electromagnetic processes for novel devices with unprecedented level of control.

Research in the second area focuses on smart, functional nano-energetics for propulsion purposes only. There has been tremendous progress in the synthesis and fabrication of nano-sized reactive materials. With significant advances in quantum chemistry and molecular dynamics over the last decade, as well as a broader understanding of the properties of nanomaterials, it may now be feasible to design a priori nanostructured reactive materials according to desired performance objectives and including controlling mechanisms at the nanoscopic and microscopic scale. Instead of being subject to uncontrolled combustion, smart nano-energetics may be activated by temperature, pressure, the presence of a particular chemical compound, or external electromagnetic stimuli, such as an electrical field or light. For example, it may be desirable to initiate a reaction at a particular temperature, to release a particular compound at a particular temperature, to turn on or turn off a reaction, have tailored ignition properties, or to accelerate or slow a reaction with time or location.

Research in the third area would allow the Air Force to capitalize on the higher efficiencies, and increased performance options made possible by taking rocket and other propulsion systems to increasingly high pressures. As this necessarily pushes materials and structures to correspondingly extreme limits, it becomes essential to take into consideration the dynamics of combustion processes, as higher pressures lead to increased amplitudes of fluid-dynamic and thermochemical events and fluctuations, in a wider spectrum of time scales. Mathematical and experimental analysis of these dynamics at higher levels of fidelity also lead to a "big data" problem. It becomes necessary to combine and dynamically integrate multi-fidelity simulations and experimental measurements or monitoring, with the goal of systematically performing modeling, analytics, statistics, and dynamic data driven validation for chemical propulsion.

Research in the fourth area aims to combine both electrochemical and mechanical functionalities in a single unit in which energy storage can be accomplished by materials and structures that simultaneously manage mechanical stress, including peak values encountered during launch.

All fundamental research ideas relating to space propulsion and power are of interest to this program in addition to the examples given above, but researchers should also consult the programs in Plasma and Electro-Energetic Physics, Materials with Extreme Properties, Theoretical Chemistry and Molecular Dynamics, Mechanics of Multifunctional Materials and Microsystems, Computational Mathematics, and other programs as described in this announcement to find the best match for the research in question. Researchers are highly encouraged to consult this link for the latest information.

Proposers are encouraged to contact the Program Officer prior to developing a full proposal by email to discuss the current state of understanding, how the research would advance it, the approximate cost for a three (3) -to five (5) -year effort, and if there are any specific submission target dates.


Agile Science of Test and Evaluation (T&E)

Program Description: The Agile Science of Test and Evaluation (T&E) program supports basic research inventing and innovating revolutionary capabilities responsive to the Air Force T&E community. Crossing scientific frontiers necessitates enhancing and pioneering test and measurement capabilities. The program sponsors basic research in areas enabling metrology and facilitating correct and comprehensive interpretation of test information. Agile science of test and evaluation leads to improving the ability to analyze and model operational environments, pursue science discoveries, and accelerate research & acquisition. The AFOSR T&E program encompasses six broadly-defined, overlapping thrust areas: Aeroelasticity and Aerodynamics, Enabling Materials and Processes, Hypersonics, Information Management and Fusion, Sensors and Electromagnetics and Science of Integrated Risk Assessment. The Program is closely aligned with other AFOSR science areas advancing experimental methodologies and merging scientific disciplines.

Basic Research Objectives: The AFOSR T&E program is closely engaged with technical experts at the Air Force Test Center (AFTC) organizations including Arnold, Edwards, Eglin and Holloman Air Force Bases, who help guide the program on basic research objectives. Basic research in areas that advance the science of testing is broadly defined and spans mathematics as well as most disciplines in engineering and the physical sciences. Areas include, but are not limited to:

  • Novel measurement techniques, materials, and instruments that enable accurate, rapid, and reliable test data collection of physical, chemical, mechanical, and flow parameters in extreme environments, such as those encountered during transonic flight, hypersonic flight, and the terminal portion of weapons engagement;
  • Accurate, fast, robust, integrals models reducing requirements to test or help provide greater understanding of test results;
  • Advanced algorithms and computational evaluation techniques that are applicable to new generations of computers, including massively parallel, quantum, and neuromorphic machines;
  • Advanced algorithms and test techniques that allow rapid and accurate assessment of devices and software to cyber vulnerability;
  • New processes and devices that increase bandwidth utilization and allow rapid, secure transfer of test data to control facilities during test;
  • Advanced mathematical techniques that improve design of experiment or facilitate confident comparison of similar but disparate tests;
  • Advanced models of test equipment and processes that improve test reliability and efficiency;
    The portfolio also seeks basic research in other T&E areas, not listed above, that may advance the science of test and contributes to the development of knowledge, skills, and abilities for the AF T&E community.

You are highly encouraged to contact our Program Officer prior to developing full proposals to briefly discuss program relevance. You should be prepared to explain why your proposed effort should be considered basic research, how it is unique to Test Science, and demonstrate an awareness of the Air Force T&E process.

Collaborative efforts with the Air Force Test Center and Air Force Research Laboratory are encouraged, but not required.