1. February 7, 2003MDO - 0 Multidisciplinary Design Optimization Activities at CASDE, I I T, Bombay http://www.casde.iitb.ac.in/MDO/activities-at-a-glance.ppt

2. February 7, 2003MDO - 1 Aug 1999 - CASDE initiates MDO activities Aug 2000 - First meeting of SIG-MDO Jan 2001 - Professional Development Course on MDO Jun 2002 - Second meeting of SIG-MDO, Workshop on MDO Feb 2003 - Third Meeting of SIG-MDO Sep 2003 - International Conference on MDO MDO@CASDE Over the Years

3. February 7, 2003MDO - 2 Design / MDO Studies @CASDE AEW System Level Optimization Aero-elastic Design of Transport A/C wings Aircraft Intake (3D-Duct) design Low Fidelity Analysis High Fidelity Analysis (CFD)

4. February 7, 2003MDO - 3 Design / MDO Studies @CASDE MDO Studies in formative stages  Hypersonic Vehicles - Integrated System Optimization (with DRDL)  Launch Vehicles - Reliability Based Design (with VSSC)  Launch Vehicle – Simultaneous optimization of trajectory & system (with VSSC)

5. February 7, 2003MDO - 4 RotodomePlatformRadarHeat exchanger AEW System P, H, V, C L Mission D2 D3 P H, V D4 H, V, C L D1 E W HX C D,H D, TL, WEWRWR QrB Ant L Ant W Ant W Rot C D,R W ds User requirements DC Design Optimization of AEW

6. February 7, 2003MDO - 5 Stage I : Analysis based on empirical formulae Stage II : semi-empirical analysis realistic aerodynamic loading - VLM simplified structural analysis - EPM Stage III : Hi-fidelity analysis with aeroelasticity VLM FEM - NASTRAN MDO of Transport Aircraft Wing

7. February 7, 2003MDO - 6 ~150 seater aircraft Mission profile shown B 737-200 candidate for numerical study 12 34 5 6 78 Takeoff at sea level d ≤ 2150 m Climb to 11000 m at best ROC ≥ 11 m/s Loiter 45 min (Reserve) Land at sea level d ≤ 1220 m Descend to 1500 m Cruise for 3000 Km at best range M ≥ 0.74 MDO of Transport Aircraft Wing – Baseline Problem

8. February 7, 2003MDO - 7 Simultaneous aerodynamic and structural optimization variables - wing aerodynamic shape + wing structural sizing constraints - mission, aerodynamics, structural, aeroelastic Optimizers : FFSQP / NPSOL (SQP) Aerodynamic analysis : Vortex Lattice Method (VLM) Structural analysis : Medium fidelity – Equivalent Plate Method (EPM) High fidelity – Finite Element Method (MSC NASTRAN) MDO of Transport Aircraft Wing Analysis tools MDO Problem

9. February 7, 2003MDO - 8 Aerodynamic Geometry Planform Geometric Pre-twist Camber Wing t/c y x single sweep, tapered wing divided into stations S, AR,,  c itp b/2  c root AR = b 2 /S = c itp / c root Wing stations MDO of Transport Aircraft Wing

10. February 7, 2003MDO - 9 MDO of Transport Aircraft Wing Structural Geometry Cross-section Box height Skin thickness Spar/ribs y A A A x A symmetric front, mid & rear boxes r 1, r 2 l1l1 l2l2 c r 1 = l 1 /c r 2 = l 2 /c

11. February 7, 2003MDO - 10 MDO of Transport Aircraft Wing Function Evaluations Structural Stresses (  x,  y,  xy ) Structural Weight (Wt) Deformation Function (W(x,y)) / Nodal displacements Aerodynamic & Mission C L,sectional C l, C Di (VLM) M div (semi-empirical) & C Do (empirical) V stall,, Takeoff & Landing Distance Ceiling, ROC, Cruise Mach No. Geometric Fuel volume (V f )

12. February 7, 2003MDO - 11 MDO of Transport Aircraft Wing Loads Load case - quasi-static pull-up maneuver Aerodynamic pressure loads Engine loads Inertia Relief Fuel Weight Inertia Relief Wing Mass Inertia Relief Both are distributed as equivalent uniform pressures over wing stations

13. February 7, 2003MDO - 12 MDO of Transport Aircraft Wing Aerodynamic A rs tsts h’2h’2 h’1h’1 h root r2r2 r1r1 d/ch/c ii AR W/S StructuralAerodynamic System Analysis Structural VfVf Wt  M dd d to RCLCL ClCl C do

14. February 7, 2003MDO - 13 MDO of Transport Aircraft Wing Aerodynamic A rs tsts h’2h’2 h’1h’1 h root r2r2 r1r1 d/ch/c ii AR W/S StructuralAerodynamic Structural VfVf Wt  M dd d to RCLCL ClCl VLM FEM C do

15. February 7, 2003MDO - 14 MDO of Transport Aircraft Wing Aerodynamic A rs tsts h’2h’2 h’1h’1 h root r2r2 r1r1 d/ch/c ii AR W/S StructuralAerodynamic Structural VfVf Wt  M dd d to RCLCL ClCl VLM FEM C do

16. February 7, 2003MDO - 15 MDO of Transport Aircraft Wing Aerodynamic A rs tsts h’2h’2 h’1h’1 h root r2r2 r1r1 d/ch/c ii AR W/S StructuralAerodynamic Structural VfVf Wt  M dd d to RCLCL ClCl VLM FEM C do Fidelity level for M dd and C do ?

17. February 7, 2003MDO - 16 Optimizer FSQP INTERFACEINTERFACE History Block Input Processor Output Processor Aerodynamics (VLM) Structures MSC/ NASTRAN NASTRAN Interface Analysis Block Aeroelasticity Iterator Optimization Framework Architecture MDO of Transport Aircraft of Wing

18. February 7, 2003MDO - 17 MDO of Transport Aircraft Wing For more information http://www.casde.iitb.ac.in/MDO/ Contact : mujumdar@aero.iitb.ac.in

19. February 7, 2003MDO - 18 3D-Duct Design Composite team ADA, Bangalore CFD Centre, IIT Bombay CASDE, IIT Bombay Bring in CFD into Optimization loop Commercial codes? In-house codes?

20. February 7, 2003MDO - 19 3-D Duct Design Design Problem in Brief Entry Exit Location and shape known Geometry of duct from Entry to Exit ? Pressure Recovery? Distortion? Swirl?

21. February 7, 2003MDO - 20 3D-Duct Design Parametrization Y X Z X Duct Centerline A X Control / Design Variables Y m, Z m A L/3, A 2L/3 Cross Sectional Area

22. February 7, 2003MDO - 21 Y X Z X Duct Centerline A X Control / Design Variables Y m, Z m A L/3, A 2L/3 Cross Sectional Area 3D-Duct Design Parametrization

23. February 7, 2003MDO - 22 Typical 3D-Ducts Generated

24. February 7, 2003MDO - 23 3D-Duct Design Using Low Fidelity Analysis Low Fidelity Design Criteria (Constraints) Wall angle < 6° Diffusion angle < 3° 6 * Equivalent Radius < ROC of Centerline Low fidelity analysis for pressure recovery (Objective function) No low fidelity analysis for distortion or swirl For results & discussion http://www.casde.iitb.ac.in/MDO/3d-duct/

25. February 7, 2003MDO - 24 3D-Duct Design Using High Fidelity Analysis Low Fidelity Design Criteria (Constraints) Wall angle < 6° Diffusion angle < 3° 6 * Equivalent Radius < ROC of Centreline CFD (Fluent) for pressure recovery & distortion Doyle Knight’s Group @Rutger’s University Optimization of width-depth of bump for minimising distortion. Grid quality required to capture distortion?

26. February 7, 2003MDO - 25 3D-Duct Design Using High Fidelity Analysis ? X 1-MIN X 1-MAX X 2-MAX X 2-MIN Domain for search using high fidelity code is large

27. February 7, 2003MDO - 26 3D-Duct Design Using High Fidelity Analysis Low Fidelity Design Criteria Wall angle < 6° Diffusion angle < 3° 6 * R EQ < ROC Fluent for CFD RSM / DOE DACE X 1-MIN X 1-MAX X 2-MAX X 2-MIN

28. February 7, 2003MDO - 27 3D-Duct Design Using High Fidelity Analysis Low Fidelity Design Criteria Wall angle < 6° Diffusion angle < 3° 6 * R EQ < ROC Fluent for CFD RSM / DOE DACE X 1-MIN X 1-MAX X 2-MAX X 2-MIN http://www.casde.iitb.ac.in/MDO/3d-duct/

29. February 7, 2003MDO - 28 MDO Framework Easy integration of analysis modules Support for distributed analysis Optimization environment... Salas & Townsend AIAA-98-4740 Commercial Frameworks are available

30. February 7, 2003MDO - 29 Why do you want my program? I have a new version of analysis software You have to know my code to be able to execute it! (it’s all in Russian) System Designer’s Nightmare! I cannot find the correct tuning parameters! MDO Framework Issues

31. February 7, 2003MDO - 30 MDO Framework Issues Aerodynamics Expert Structures Expert Controls Expert System Analysis Analysis codes should reside with experts. System analysis should execute analysis codes on experts’ computers.

32. February 7, 2003MDO - 31 Framework Development @CASDE Distributed computing (CORBA based) Database driven Tools to integrate analysis modules using wrappers Automatic data exchange between analysis modules

33. February 7, 2003MDO - 32 Framework Architecture Database Configuration Manager Execution Manager Sequence Logic MDO Controller Name Server Data Server OPT1 Optimizer Manager OPT2OPT3 AM1 Analysis Manager AM2AM3 GUI

34. February 7, 2003MDO - 33 Optimization Issues Gradient based optimization Evaluation of gradients? Finite Difference. Requirements on convergence more severe than that required for engineering analysis. Noisy functions? X f

35. February 7, 2003MDO - 34 User Supplied Gradients Complex Analysis Code in Fortran Manually extract sequence of mathematical operations Code the complex derivative evaluator in Fortran Manually differentiate mathematical functions - chain rule FORTRAN source code that can evaluate gradients

36. February 7, 2003MDO - 35 User Supplied Gradients Manually extract sequence of mathematical operations Use symbolic math packages to automate derivative evaluation Code the complex derivative evaluator in Fortran Complex Analysis Code in FORTARN FORTRAN source code that can evaluate gradients

37. February 7, 2003MDO - 36 User Supplied Gradients Parse and extract the sequence of mathematical operations Use symbolic math packages to automate derivative evaluation Code the complex derivative evaluator in Fortran Complex Analysis Code in FORTARN FORTRAN source code that can evaluate gradients

38. February 7, 2003MDO - 37 Gradients by ADIFOR Complex Analysis Code in FORTARN FORTRAN source code that can evaluate gradients Automated Differentiation Package Euler

39. February 7, 2003MDO - 38 Presentation made on behalf of CASDE PM Mujumdar, K Sudhakar Amitay Isaacs, SK Sane, AG Marathe VISIT http://www.casde.iitb.ac.in/ for information on MDO & Other activities