1. April 4 - 5, 2000 at Lewis Field GLENN RESEARCH CENTER Aero-Space Propulsion Simulation and Modeling Dr. John K. Lytle Chief, Computing and Interdisciplinary Systems Office

2. 2 Provide next generation design tools and experimental aircraft to increase design confidence, and cut the development cycle time for aircraft in half. NASA Goals Directly Supported by Simulation and Modeling

3. 3 High Fidelity, Physics-based Simulations Combustion Turbomachinery Aeroelasticity Probabilistic Methods Full System Virtual Design Environment, Life Cycle Simulation Outline Advanced Space Transportation Program (MSFC) High Performance Computing and Communications Program (ARC) Intelligent Synthesis Environment Program (LaRC) Intelligent Systems Program (ARC) Information Technology R&T Base Program (ARC) Aero-Space Propulsion and Power R&T Base (GRC)

4. 4 Fuel Nozzle Flow Cold and Hot Isotherm Interactions Midplane Temperature Contour Midplane Total Pressure Contour The National Combustion Code is an integrated system of computer codes that takes advantage of solid modeling and automated meshing of complex geometries. The National Combustion Code uses unstructured meshes and parallel computing. Physical models include: a turbulence module containing the nonlinear k-epsilon models; conventional reduced chemical kinetics or the Intrinsic Low Dimensional Manifold (ILDM) approach; a spray module; and a joint probability density function for species and enthalpy. The National Combustion Code

5. 5 APNASA 21 Blade Row Compressor Simulation Turnaround Time Reduced by a Factor of 400:1 COMPUTER HARDWARE IMPROVEMENTS BASELINE ANALYSIS 1992 PARALLEL PROCESSING ALGORITHMIC CHANGES INCREASED RESOLUTION ~ ÷ 40 ~ 2.4 X ~ ÷ 6 Factors Influencing Turnaround Time Estimated Turnaround Time Hours ~ ÷ 4

6. 6 Dynamic Stress Prediction Unsteady Aerodynamic Loading Forced Response Aeroelastic Analysis using TURBO TURBO version for fluid-structure interaction analysis being developed –three-dimensional, viscous, unsteady aerodynamics –Purge flow, real gas effects, K-  Baldwin-Lomax turbulence models –phase-lagged boundary conditions reduce computational domain to one blade passage per blade row –dynamic grid deformation to simulate blade vibration Code validated for flutter analysis –Pratt & Whitney, Honeywell and Rolls-Royce Allison used code on in-house data to predict flutter Validation in progress for forced response –GE validating the code using in-house data Mass Flow Flutter Mode 1 Mode 2 Aero-Damping No Flutter Flutter

7. 7 Probability of Failure Response (stress) Resistance (strength) Structural Response Probabilistic Loads P  Mechanical P  Thermal Information for Reliability & Risk Assessment  Probability of Occurrence Probabilistic Materials Behavior P Geometry and Material Multidisciplinary Probabilistic Heat Transfer/Structural analysis code Probabilistic Simulation of Component Reliability using NESTEM

8. 8 Validated Models  Fluids  Heat Transfer  Combustion  Structures  Materials  Controls  Manufacturing  Economics Rapid Affordable Computation of:  Performance  Stability  Cost  Life  Certification Requirements Integrated Interdisciplinary Analysis and Design of Propulsion Systems High Performance Computing  Parallel Processing  Object-oriented Architecture  Expert Systems  Interactive 3-D Graphics  High Speed Networks  Database Management Systems A Numerical Test Cell for Aerospace Propulsion Systems

9. 9 Aero-Space Propulsion Simulation and Modeling Government NASA ARC LaRC MSFC Air Force Research Laboratory Naval Air Research Center Arnold Engineering and Development Center Department of Energy Industry General Electric Pratt&Whitney Honeywell Rolls-Royce Allison Williams Intl. Teledyne Continental Boeing Lockheed-Martin A Government/Industry/ University Partnership University Stanford Cleveland State Winston-Salem IUPUI Mississippi State

10. 10 Numerical Zooming and Geometry Access Standards through NPSS for physics based modeling NPSS Common System Model expected to save Aircraft Industry $50M/year Simulation Environment Computationally efficient (cross-platform operation, parallel processing) Modular design (object- oriented:“Plug-n-Play” system model assembly, easily modified and expanded) Provide a common modeling tool for U.S. Government, aerospace industry, and academia

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12. 12 The Road to Full 3D Overnight Engine Simulation Full 3-D Primary Flow Path Scheduled for Completion 2Q FY2001 High Pressure Core Scheduled for Completion 3Q FY2000 Compressor Simulation Completed 1998 Combustion Subsystem Completed 4Q FY1999 Turbine Subsystem Completed FY1998 Single Stage Completed 1990 Single Blade Row Completed 1985 CD-00-79981 Fan/Booster Scheduled for Completion 3Q FY2000 NPSS for Space Transportation

13. 13 Engine-Airframe Structural Simulations Provide High Fidelity Analysis and Assessment of Blade-Out Event NASA Glenn, General Electric Aircraft Engines, Pratt & Whitney, and Boeing have teamed to develop new simulation tools for engine-airframe structural systems. Development of these tools will enable high-fidelity analyses of blade-out events, more credible design of engine containment systems and improvements in blade-out margin-of-safety predictions. Mathematical Modeling of Turbomachine Rotors Physics Based Blade Loss Modeling Industry/Government Standard Simulation Procedures

14. 14 ISE Vision and Long-Term Goal Vision To effect a cultural change that integrates into practice widely- distributed science, technology and engineering teams to rapidly create innovative, affordable products Vision To effect a cultural change that integrates into practice widely- distributed science, technology and engineering teams to rapidly create innovative, affordable products Long-Term Goal To develop the capability for personnel at dispersed geographic locations to work together in a virtual environment, using computer simulations to model the complete life-cycle of a product/mission with near real-time response time before commitments are made to produce physical products Long-Term Goal To develop the capability for personnel at dispersed geographic locations to work together in a virtual environment, using computer simulations to model the complete life-cycle of a product/mission with near real-time response time before commitments are made to produce physical products

15. 15 ISE Will Enable Tomorrow What Cannot Be Easily Done Today Comprehensive life-cycle trade-studies to: – reduce design cycle time and testing – reduce redesign and rework, – reduce maintenance costs – increase performance and safety Bound uncertainties arising from assumptions, scarcity of knowledge and unknowns Comprehensive and rapid mission life-cycle simulations will minimize the risks and maximize the benefits Provide a means for productive teaming of the best and brightest people and capabilities Create and assess new innovative design options and new technologies from anywhere and at anytime A

16. 16 Summary Revolutionary advances in simulation and modeling will lead to increased design confidence that translates into significant reductions in aerospace propulsion: Development, manufacturing and certification time and cost Maintenance and operations costs Greater opportunities to introduce advanced technologies that “buy their way” into new products Government/Industry/University partnerships are required to accomplish these goals and to ensure technology transfer Useful products must be delivered throughout the Program on a frequent basis to sustain interest

17. 17 Engineering Applications Applications Computing Testbeds SimulationEnvironment Code Parallelization 3–D Subsystems/System  Gov’t/Industry Collaborative Effort  Object - Oriented Programming  CAD Geometry Interface  Coupled Aero-Thermal- Structural Analysis  Multi-physics Methods  0–D Engine/1–D Compressor  0–D Core/3–D LP Subsystem  High-Speed Networks  PC Cluster  Metacenter Computing Seamless Integration of Data, Analysis Tools and Computing Resources High Fidelity, Large Scale Simulations Low-Cost, Distributed Parallel Computing Major Elements of NPSS

18. 18 APNASA Coupled Flow Simulation of High Pressure-Low Pressure Turbines Results in Significant Fuel Savings Objective: Create a high-fidelity computer simulation of the flow through a full modern high bypass ratio turbofan engine. Approach: Using a modular approach to the full engine simulation goal, a flow simulation of the tightly coupled high pressure and low pressure turbines has been completed. The computer simulation was performed using NASA’s 3-D average passage approach (APNASA). The simulation was done using 121 processors of a Silicon Graphics Origin cluster with a parallel efficiency of 87% in 15 hours. Significance: The accurate and rapid simulation of a large turbine subsystem enabled designers to reduce turbine interaction losses in dual-spool engines by 50%. This will result in a $3 million/year savings in fuel costs for a typical fleet of commercial aircraft. Point of Contact: Joseph P. Veres (216)433-2436 Low Pressure Turbine High Pressure Turbine Transition Duct