N231-007 TITLE: DIGITAL ENGINEERING - Digital Modelling and Simulation of Maneuvering Hypersonic Weapons

OUSD (R&E) CRITICAL TECHNOLOGY AREA(S): Hypersonics

The technology within this topic is restricted under the International Traffic in Arms Regulation (ITAR), 22 CFR Parts 120-130, which controls the export and import of defense-related material and services, including export of sensitive technical data, or the Export Administration Regulation (EAR), 15 CFR Parts 730-774, which controls dual use items. Offerors must disclose any proposed use of foreign nationals (FNs), their country(ies) of origin, the type of visa or work permit possessed, and the statement of work (SOW) tasks intended for accomplishment by the FN(s) in accordance with the Announcement. Offerors are advised foreign nationals proposed to perform on this topic may be restricted due to the technical data under US Export Control Laws.

OBJECTIVE: Develop and advance computational simulation tools for modeling of weapon maneuvers in the hypersonic flight regime.

DESCRIPTION: The maneuverability of hypersonic vehicles offers a significant tactical advantage as maneuvering can increase both weapon survivability and lethality, especially in the endgame scenario. However, it is important to understand the design tradeoffs between maneuverability and effectiveness (e.g., range, impact velocity, etc.) to ensure a high probability of mission success. Simulating the vehicle environment and response over the entire trajectory with high-fidelity modeling tools is often intractable due to the high computational cost. In practice, low-fidelity physics models (i.e., zeroth to first-order models) are used to simulate the environment and response of the vehicle across its intended trajectory. These low-fidelity models often neglect a large degree of the complex physics encountered in the hypersonic regime. To ensure vehicle performance and mission effectiveness, it is critical that computational tools are able to accurately (90 � 95% accurate) and efficiently predict the vehicle trajectory and its ability to maneuver during the glide phase and at endgame. New computational tools and methods are desired, which leverage high-performance computing and surrogate/reduced-order modeling without degrading model fidelity while utilizing reduced computational resources for full-trajectory and mission-effectiveness simulations. 90 - 95% accuracy is a reasonable goal. The modeling approach will consist of a rocket boosted hypersonic glide body. The simulation shall begin after rocket separation. The glide body should glide along a predetermined powered trajectory and perform maneuvers along the ingress to the target. Final selection of the study vehicle and associated propulsion system will be made in Phase I with government agreement. The study vehicle should focus on phenomena in the Mach 5 � 10 range. The end simulation shall be capable of sustained (minutes) in this regime.

Proposed solutions should include any relevant expertise and experience in predicting high-Mach aerodynamics and development of associated simulation models. Demonstrated experience in low-order modeling of high-fidelity physics is a factor. Consideration could be given to interface definition for compatibility with other high-fidelity codes, model attributes of relevant physics in the regime, computational cost, and potential for integration into existing simulation tools like CREATE AV. Company codes are acceptable but any new methods must be adaptable to government codes like CREATE AV. Consideration should be given to the appropriate balance of computational cost, code complexity, and accuracy of prediction. Uncertainty quantification of the tool is strongly encouraged.

PHASE I: Review the accuracy and cost of current industry standard existing computational tools/methods at simulating the trajectory (including boost, ballistic, cruise, and terminal phases), accuracy, and computational cost of hypersonic maneuvering vehicles. Assessments of computational tools should address the adequacy and fidelity of physical models, including, but not limited to, aerodynamic models and flight trajectory models. Identify the gaps/limitations of existing tools/methods at accurately predicting vehicle performance over the full trajectory. For methods that are deemed inadequate, describe how the method can be updated to make it suitable for hypersonic applications. Any description of method development should capture the work required and associated risks. A canonical vehicle geometry and associated source data (e.g., flight test data, ground test data, etc.) should be identified to support and validate any proposed method development to occur in Phase II. Availability of validation data is a consideration.

Availability of new or existing approaches to reduce the computational burden associated with running high-fidelity prediction tools should be evaluated. The Phase I product should focus on any existing methods that could significantly reduce computational cost (e.g., CPU count, CPU hours, memory allocation, etc.), while not substantially impacting simulation accuracy. The Phase I report should provide a detailed plan for Phase II including schedules, important milestones, specific tasking, and availability of computational resources. If use of DoD High Performance Computing resources is required, resource requirements should be identified in detail. Maximum use of in-house resources is encouraged. The Phase I effort will include prototype plans to be developed under Phase II.

PHASE II: Develop the computational tools/methods necessary to accurately predict vehicle response over the vehicle's trajectory at reduced cost (50 � 75% computational cost reduction target). Any computational tools developed should execute quickly on modest hardware such that trajectory analyses can be performed with minimal turnaround time. The desired level of model fidelity and complexity should be considered above that which is typically used in conceptual design tools. Multiple analyses per day on multiple (< 10) computing platforms is a reasonable target. Incorporate newly developed tools/methods (e.g., ROM for aerodynamics) into existing DOD toolsets (e.g., CREATE-AV products or others). Exercise updated toolsets using a generic hypersonic vehicle geometry and evaluate predictive capability against available test data. Determine metrics for quantifying uncertainty in simulation predictions. Establish confidence intervals using uncertainty quantification toolsets/methods.

PHASE III DUAL USE APPLICATIONS: Verify and validate (V&V) the new methods based on available test data. Methods should be updated based on the V&V effort. Additional analyses should be performed on a Navy relevant configuration.

With the push for commercial aircraft operating at hypersonic speeds now part of the national discussion, the tools and methods developed under this SBIR topic will have utility to the design and development of future commercial hypersonic platforms.

REFERENCES:

1.       Bertin, J. J., & Cummings, R. M. (2006). Critical hypersonic aerothermodynamic phenomena. Annu. Rev. Fluid Mech., 38, 129-157. https://doi.org/10.1146/annurev.fluid.38.050304.092041

2.       Bertin, J. J. (1994). Hypersonic aerothermodynamics. AIAA. https://books.google.com/books?hl=en&lr=&id=NKOIAY_Cj2kC&oi=fnd&pg=IA3&dq=Hypersonic+Aerothermodynamics&ots=s5hkXdUREQ&sig=XtmVHoDzuVHdmsPUoVRHeOuxM1o#v=onepage&q=Hypersonic%20Aerothermodynamics&f=false

3.       Heiser, W. H., & Pratt, D. T. (1994). Hypersonic airbreathing propulsion. AIAA. https://books.google.com/books?hl=en&lr=&id=d1sQvT2_kMsC&oi=fnd&pg=IA4&dq=Hypersonic+Airbreathing+Propulsion&ots=f8xchg_WcA&sig=IIDSJcb0MVRkbYUCUDoCuRagVPM#v=onepage&q=Hypersonic%20Airbreathing%20Propulsion&f=false

 

KEYWORDS: Hypersonics; Maneuver Prediction; Computational Aerodynamics; Aircraft Performance; Digital Engineering; Weapons

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