PHASE II: The concept identified in phase I will be designed and developed into a prototype modular sensor electronics system that has the capability to fuse sensor inputs from a variety of sensor types. A demonstration of the system operation will be performed. A commercialization plan, including descriptions of specific tests, evaluations, and implementations to be performed will be developed.
PHASE III DUAL USE APPLICATIONS: Micro/miniature disparate sensors are being used in everything from automobiles to household appliances and consumer electronics. Being able to easily control the wealth of information in a cost effective manner is essential, and will be an important application of this topic. Phase III efforts would include integration of the prototype demonstrated in Phase II into the Kinetic kill vehicle Hardware In the Loop Simulator (KHILS) facility at AFRL/MNG for characterization and evaluation.
REFERENCES:
1. New World Vistas: Air and Space Power for the 21st Century, Munitions Volume. DTIC AD Number: ADA309598.
2. "MIRIADS: Miniature InfraRed Imaging Applications Development System Description and Operation," Baxter, Christopher R.; Massie, Mark A.; McCarley, Paul L.; Couture, Michael E., Proc. SPIE Vol. 4369, p. 129-139.
KEYWORDS: Electro-magnetic Sensors, Integrated Sensors and Electronics, Integrated Sensor and Image/Signal Processing, Sensor Fusion, Conventional Weapon Guidance & Control, Conventional Weapon Guidance Integrated Fuzing, Conventional Weapons Integrated Electronics Suite, Biologically Inspired Sensor and Control Processing
AF04-175 TITLE: A Hydrodynamic-Stochastic Neutralization Model for Biological Agent Defeat
TECHNOLOGY AREAS: Chemical/Bio Defense, Weapons
OBJECTIVE: Develop a hydrodynamic-stochastic neutralization model and couple it with an incompressible, turbulent computational fluid dynamics code.
DESCRIPTION: Many biological agents may be stored in liquid solution, e.g., a saline based solution such as blood plasma. It is desirable to defeat this stored agent by mechanically damaging the associated containers and by then preventing a dangerous release of agent. The release of agent may be mitigated by injecting a neutralizer at the time of impact. In theory, the neutralizer will diffuse convectively (as forced by projectile motion) and will neutralize agent on a particle-by-particle basis. Given the nature of microscopic particles, uncertainly casts some doubt on the likelihood of success for this defeat mechanism. For instance, the initial quantity and viability of the agent are unknowns. The dispersal of agent particles within the container is also unknown. These uncertainties make it difficult to compute time accurate predictions of agent viability in space. Given that the agent and neutralizer consist of microscopic bodies it is desirable to address them via probability density functions defined over the container’s interior. In turn, these functions may be used to build probability representations of agent propagation and viability. The fluid dynamics of this problem are solved through deterministic CFD methods. The agent and neutralizer growth and death equations should be cast in a stochastic CFD framework. The transport of these species across fluid cell boundaries is very important, and the method should be consistent for stochastic methods. Properties directly associated with the agent are represented by random variables defined in time and space. An example output of this research is a three-space map of biological agent viability in time. A similar map set can be developed for neutralizer potency. These maps are characterized by probability contours. A probability of zero constitutes the absence of viability whereas a probability of one constitutes live, infectious agent. The strength of this approach is that probability modeling allows the use of a larger state space. That is to say, a particle of agent may have varying degrees of viability. A stochastic model should be selected for the chosen biological agent and neutralizer and then be integrated into a three-dimensional unsteady, incompressible CFD code with moving boundary capability. Problems of interest entail the passage of a solid body through a fluid mass. The neutralizer may enter the agent fluid through the wake of the solid body. Cavity formation and collapse may be important aspects of the problem. The resulting fluid flow will transport the neutralizer throughout the container. Complex neutralization schemes for biological agents pose serious questions concerning efficacy. It is incorrect to assume that the agent may be neutralized by the simple act of injecting neutralizer into the fluid volume. This effort is designed to produce a high fidelity computational tool that may be used to study the evolution of agent in the presence of a neutralizer. The end product of this research allows certain neutralization schemes to be studied. Currently, there are no effective tools for simulating the time-dependent performance of these neutralization methods.
PHASE I: Conceptualize and design an innovative approach for integrating a stochastic model for a biological agent and neutralizer in to a three dimensional incompressible turbulent CFD framework with moving boundaries.
PHASE II: develop the stochastic model(s) to cover a wide range of biological agent and neutralizer combinations. Integrate the models into an incompressible turbulent CFD framework. Then perform studies to demonstrate the performance of various neutralization approaches.
DUAL USE COMMERCIALIZATION: The results of this SBIR would be useful for modeling industrial processes involving liquids, and liquid transport systems. Military uses involve novel agent
defeat warhead designs.
REFERENCES: 1. Alibek, Ken, “Biohazard : The Chilling True Story of the Largest Covert Biological Weapons Program in the World-Told from the Inside by the Man Who Ran It Towards a Coherent Strategy for Combating Biological Weapons of Mass Destruction,” Random House, 1999.
2. Volpe, Philip, “Towards a Coherent Strategy for Combating Biological Weapons of Mass Destruction,” (ADA308957).
3. Seebaugh, William R.; Ganong, Gary P., “Summary of Collateral Effects Experiments Conducted During Fiscal Year 1996,” LAT990075 (ADA382603).
4. Schowalter, Walter, “Mechanics of Non-Newtonian Fluids,” Pergamon Press, 1978.
KEYWORDS: Hydrodynamic, reaction kinetics, neutralization, stochastic models, agent, biological
AF04-177 TITLE: Multi-Mode Mobility
TECHNOLOGY AREAS: Weapons
OBJECTIVE: Develop and advance enabling technologies to allow a small device to transition between air and land mobility.
DESCRIPTION: In the ever changing battlespace environment, the ability to have a Micro Air Vehicle (MAV) change its physical shape by collapsing its wings on to its airframe could enable its new geometry to take advantage of an alternate mode of mobility and thus enhance its operational utility. This technology would allow a single vehicle the ability to perform multiple missions. An example would be to have a MAV fly to the top of a building, land, and then change geometry, and then move to the edge of the roof (rolling, crawling, hopping, etc.) and collect video imagery. Following mission completion, the device would reconfigure its geometric shape, fly off the building, and then return to its home base or continue its mission. This ability to change physical shape or “morph” will require innovative technologies such as miniature smart structures, power miniaturization and management, micro conformal sensors, and MEMS technologies. The major technical risks will be in the development of a small power system, and in the miniaturization of required components. It is envisioned that this technology will be applied to an MAV with a maximum wingspan of 12 in and weighing less than 1.0 lb, and will have the ability to maximize mission effectiveness to support the warfighter.
PHASE I: Define the proposed concept, identify key technologies, and predict the performance of the proposed design of a multi-mode mobility device using simulation techniques. Identification of critical parameters and application to Concept of Operations (CONOPS) are key.
PHASE II: Finalize the design of the multi-mode mobility device. Develop an operable prototype or suitable device that demonstrates the intended technological concept. Final report should include how CONOPS are supported, and how multi-mode mobility transformation affects overall robot device architecture.
PHASE III DUAL USE APPLICATIONS: Technology developed on this program will have military application to future urban environments. The morphing technology to be demonstrated under this topic will provide the enabling technology for weapons to fly, perch, crawl and then fly again; necessary capabilities of a urban weapon system. The morphing technologies can be applied to commercial robotic markets, i.e. wheelchairs that can climb stairs, automobiles that can morph into trucks or amphibious vehicles.
REFERENCES:
1. AFRL/MN Home Page: http://www.mn.afrl.af.mil
2. Micro Air Vehicles – Towards a New Dimension in Flight: http://www.darpa.mil/tto/mav/man_auvsi.html
3. Ifju, Peter, G., et al, “Flexible-Wing-Based Micro Air Vehicles” 40th AIAA Aerospace Science Meeting and Exhibit, Paper No. 2002-0705 (2002)
4. Bachmann, R. J., Kingsley, D.A., Quinn, R. D., Ritzmann, R. E. (2002) A cockroach robot with artificial muscles, Conference on Climbing and Walking Robots (CLAWAR).
5. Birch, M.C., Quinn, R.D., Hahm, G., Phillips, S., Drennan, B., Fife, A., Verma, H., Beer, R.D., "Design of a cricket microrobot," IEEE Conf. on Robotics and Automation, April 2000, San Francisco, CA.
KEYWORDS: Multi-Mode Mobility, Micro-robots, miniature robots, flying robots, crawling robots, robotic system integration
AF04-181 TITLE: Development of Phenomenological Liquid Spray Design Tool for Augmentor Operability and Performance
TECHNOLOGY AREAS: Air Platform
OBJECTIVE: Develop and validate an advanced numerical model to predict the liquid fuel breakup in gas turbine augmentor flows.
DESCRIPTION: In gas turbine augmentor systems, fuel is injected into a high-speed vitiated air stream produced by the engine. The light off, blowout, efficiency, and screech characteristics are directly related to the behavior of the fuel/air mixture resulting from the injection process. To provide a robust, low-cost system, a typical approach for injecting fuel involves the injection of a small-diameter stream of liquid into the vitiated air stream. The injection process, while simple in concept, results in complex, rapid behavior associated with liquid column breakup, stripping, secondary atomization, transport, evaporation, and mixing prior to combustion. As a result of these complex phenomena, detailed design strategies that relate the fuel injection process to the subsequent augmentor performance are not available. As a result, optimization of augmentor performance must be done through a cut-and-try methodology, which adds to the production cost of augmented gas turbines.
Injection of a liquid stream into a high-speed crossflow is applicable to many combustion applications, including augmentors. Liquid stream injection has been studied extensively in recent years. The studies have resulted in some design tools directed at jet breakup length, jet penetration, and spray features. Despite these studies, however, wide variation in expressions describing even basic features, such as jet penetration, are apparent, reaffirming the lack of sufficient design tools. Currently, a comprehensive physics-based design code (i.e., computational fluid dynamics (CFD)) cannot deal with breakup, secondary atomization, and strong phase coupling. The most advanced codes with quick turnaround typically require an average droplet size of spherical particles (e.g., Sauter Mean Diameter), gas phase velocity, population density, and size distribution information as a function of position in space. These general spray features are present in augmentor systems, but well downstream of the key phenomena that ultimately describe the spray presentation. Hence, to provide an accurate description of the augmentor efficiency, light off, and stability, improvements in design tools, either empirical or CFD based, are required. In particular, tools that provide spatial and temporal characteristics associated with the dispersion of the fuel, evaporation, and mixing are key.
PHASE I: Develop an advanced numerical model for predicting liquid fuel jet breakup in a cross-flow. Validate the feasibility of the numerical model using existing data. Analysis of the numerical model shall include identifying deficiencies and the necessary requirements to alleviate the analytical deficiencies.
PHASE II: Identify and obtain the experimental data required to perform a prototype demonstration of the advanced numerical model to diminish the analytical deficiencies of predicting liquid fuel jet breakup in a cross-flow. This could be accomplished by identifying an experiment to be controlled exclusively by the small business or partnering with a major engine manufacturer utilizing an augmentor test with additional instrumentation, or other methods as required. Results of the numerical simulation of the experiment shall be analyzed and the advanced numerical model shall be improved and demonstrated.
DUAL USE COMMERCIALIZATION: This program will produce a numerical simulation tool that can be used to study and improve the operability of military gas turbine augmentors. This could be used in civilian aerospace applications requiring high speed flight or temporary high performance. Also, the numerical simulation software may find application in power generation duct burners for environmental pollution control. Commercial applications include the use of improved liquid jet models in CFD codes and in the design of combustors with reduced pollutant emissions and increased performance.
REFERENCES:
1. P.K. Wu, K.A. Kirkendall, R.P. Fuller, and A.S. Nejad, “Breakup Processes of Liquid Jets in Subsonic Crossflow,” J. Prop Power, 13(1), p. 64 (1997).
2. P.K. Wu, K.A. Kirkendall, R.P. Fuller, and A.S. Nejad, “Spray Structures of Liquid Jets Atomized in Subsonic Crossflows,” J. Prop Power, 14(2), p. 173 (1998).
3. K.-C. Lin, P.J. Kennedy, and T.A. Jackson, “A Review on Penetration Heights of Transverse Liquid Jets in High-Speed Flows,” Proceedings, 2002 ILASS-Americas Meeting, Madison, WI, May, 2002.
KEYWORDS: augmentor, combustor, screech, efficiency, blow out, light off, liquid jet, liquid fuel jet breakup
AF04-182 TITLE: Control of Fuel Atomization and Mixing for Emission Reduction in High Performance Gas Turbines
TECHNOLOGY AREAS: Air Platform
OBJECTIVE: Demonstrate novel fuel atomization methods for reduced emission, improved stable gas turbine combustion with high combustion efficiency, low pattern factor, and tailored thermal profiles for military applications.
DESCRIPTION: The performance of gas turbine combustors depends directly on effectively mixing fuel spray and air/gas streams. Current combustors are inherently limited by the fundamental spray quality and jet penetration limits associated with fuel spray jets. Given recent successes in control of ultra-fine sprays mixing and development of advanced numerical tools, control of atomization and mixing in realistic gas turbine combustors is now an achievable goal. The use of intelligent fuel injectors capable of producing ultra-fine spray may be the key to enabling effective interaction between spray and gas streams with improved mixing. Recent experiments have demonstrated that controlled atomization can yield reduced emissions and control of unsteadiness. These effects could result in reduced fuel consumption, augmented specific thrust, and increased control authority for future gas turbine engine combustion systems. The purpose of this program is to reduce emission and improve performance of gas turbine engines by developing new fuel atomization and mixing techniques. A related goal is to integrate development of novel fuel injection methods with advanced numerical simulation tools, which will be required to fully understand spray behavior and realize the full benefits of improved fuel atomization and mixing.
PHASE I: Provide novel fuel injectors capable of controlling variations of extremely small spray droplets and investigate spray droplet size, spray penetration, and trajectory. Integrate candidate fuel injectors into combustion systems to study atomization of hydrocarbon fuel and mixing as a function of flow rates and air-to-fuel ratios.
PHASE II: Integrate prospective fuel injectors and perform physical demonstration of the complete fuel injection system on a representative military turbine engine platform for a range of operating conditions. Demonstrate combustion performance enhancements and reduced emissions in a simulated combustion environment.
DUAL USE COMMERCIALIZATION: Commercial applications include land-based gas turbines for power generation and improved fuel mixing technologies for the automobile industry. Military applications include high-performance military engines for global power and unmanned aerial systems.
REFERENCES: 1. T. S. Snyder, T. J. Rosfjord, J. B. McVey, and L. M. Chiapetta, "Comparison of Liquid Fuel/Air Mixing and NOx Emissions for a Tangential Entry Nozzle," ASMA Paper 94-GT-283.
2. S. Birch, "Reducing Emissions," Aerospace Eng., p.6, 1999.
3. W. A. Sirignano, J. Fluids Eng., Vol. 115, p.345, 1993.
4. S. Candel, D. Thevenin, N. Darabiha, and D. Veynante, "Progress in Numerical Combustion," Combustion Science and Technology, Vol. 149, pp. 297-337, 1999.
5. F. V. Bracco, "Modeling of Engine Sprays," SAE Paper 850394, 1985.
KEYWORDS: fuel injection, increased mixing, NOx reduction, advanced numerical simulation, fuel spray droplet size distribution, dense spray, two-phase model
AF04-183 TITLE: Thermal Barrier Coating (TBC) Durability
TECHNOLOGY AREAS: Materials/Processes
OBJECTIVE: Develop the capability to assess the structural integrity and life expectancy of thermal protective coating systems for turbine engine components.
DESCRIPTION: Low-cost nondestructive inspection (NDI) methods are needed to obtain quantitative measures for TBC structural integrity and life expectancy for both as-fabricated and fielded turbine airfoils. There are three areas in which such methods are applicable: (1) maintenance inspection, (2) screening method for new coating systems, and (3) quality assurance. Premature failure of thermal protective coatings is a significant contributor to the high cost of maintaining turbine engines, and the ability to detect and predict such failures should enable the maintainer to remove components for cause rather than as a precaution. In recent years, efforts to improve coating durability has been hampered by the inability to objectively compare the relative merits of competing coating systems. Developing more reliable materials screening methods should enable the developer to rank order potential coating systems more systematically. Lastly, ensuring the quality of the applied TBC is critical to the durability and life of the coated turbine engine part. Applying the thermal protective coatings uniformly over the entire complex turbine airfoil shapes can be quite a challenging task, and any variations in the thickness, tightness of the bonding to the substrate, etc., can have a major impact on coating durability. Quantitative durability measurements of as-fabricated coatings could form a basis for an objective acceptance test. These methods could also be used to provide a baseline for future parts inspection in the field. In summary, the inspection methods to be considered in this effort must be compatible with the inspection capabilities of the shop floor of the typical manufacturing plant or the maintenance depot. For both as-fabricated and fielded parts inspection, the emphasis must be on accuracy, speed, and cost. For fielded parts inspection, the developer must remember that engine disassembly will significantly increase the cost of performing the inspection. Therefore, a reasonable effort should be made to develop methods that can be used on fully assembled engines.
PHASE I: Determine technical feasibility of incorporating existing NDI methods into an inspection protocol and breadboard device for coated components.
PHASE II: Produce a refined inspection protocol and device and apply the method to a fully assembled turbine section.
DUAL USE COMMERCIALIZATION: The potential military applications for this technology include the depot maintenance for existing fighter, bomber, and helicopter advanced engines. The potential commercial applications include manufacturing quality assurance inspections and end-user maintenance inspections of commercial aircraft and ground-based power generators.
REFERENCES: 1. Dongming Zhu and Robert A. Miller, “Evaluation of Oxidation Damage in Thermal Barrier Coating Systems,” AD Number: ADA320578 NASA, Report Number: NASA-E-10518, dated NOV 96.
2. Golam Newaz, “Effect of Damage Processes on Spallation Life in Thermal Barrier Coatings,” AD Number: ADA397661, Report Number TR-01-0652, AFRL-SR-BL, dated 09 NOV 2001.
3. Golam M.Newaz, “Damage Accumulation Mechanisms in Thermal Barrier Coatings,” AD Number: ADA352301, Report Number TR-98-0592, AFOSR, dated 03 AUG 1998.
KEYWORDS: thermal protective coatings, TBC, thermal barrier coatings, coated turbine airfoils, inspection, nondestructive inspection, TBC durability, TBC life determination
AF04-184 TITLE: Genetic Algorithm Optimized Probabilistic Maintenance Scheduling
TECHNOLOGY AREAS: Air Platform
OBJECTIVE: Development of a Genetic Algorithm (GA) based probabilistic reliability-centered maintenance scheduling tool.
DESCRIPTION: Component maintenance and replacement for a large fleet spread over many operational bases and logistic centers with differing maintenance capabilities is a difficult scheduling problem. That schedule must also be combined with an operations tempo that requires the maximum fleet readiness possible to support field operations. Genetic algorithms present an innovative approach to address the complex scheduling issue. As component life prediction methods transition from a deterministic value to a retirement for cause or probabilistic life requirement, the current scheduling and replacement part fabrication becomes a cloudy issue. The maintenance actions would no longer be planned and foreseeable years in advance. However, the distribution of the aircraft in the fleet that requires action is still predictable. Genetic algorithms offer the ability to determine if this new maintenance schedule is possible while maintaining a high level of operational readiness. The scheduling software must be able to use as input the expected life, fleet unscheduled maintenance rates (component failure rates), operational readiness, technical order required scheduled maintenance, maintenance action costs, and replacement manufacturing lead time to determine a maintenance schedule and replacement ordering schedule. The payoff is a reduced maintenance cost since more of the usable component life is used as the retirement is transitioned from deterministic to probabilistic or retirement for cause. Novel algorithms and operations must be incorporated into the algorithm to ensure convergence and to reach an optimum with such a complex problem.
PHASE I: Demonstrate an algorithm that uses multiple time, cost, and readiness constraints to produce a maintenance schedule as well as gather the constraints, costs, and other input for a fully developed code.
PHASE II: Produce a code to assess cost per engine flight hour where there is limited cost data. The code will demonstrate robustness and convergence to an optimum.
DUAL USE COMMERCIALIZATION: Military uses include satellite launch scheduling, test facility scheduling, ground transportation maintenance scheduling, etc.
Share with your friends: |