STAR Konferenz Deutschland 9.-10. November 2009 November 2009 Dr.-Ing. Andreas Wick Environmental Control Systems CFD Focal Point Airbus Operations GmbH Industrial Application of CFD in Airbus An Air Systems Perspective
Table of contents Welcome to the world of Airbus November 2009 Page 2
Table of contents The Airbus Company Aircraft Development Process Integrate, Automate, Innovate A Rigorous CFD Approach Summary November 2009 Page 3
Table of contents The The Airbus Company Aircraft Development Process Integrate, Automate, Innovate A Rigorous CFD Approach Summary November 2009 Page 4
Airbus Overview Product line ranges from 100 seater A318 to A380 with 555 seats 52,000 employees around the world, including France, Germany, Spain, the UK, North America, China, India, Japan and Russia A global network of over 312 customers and 315 operators Close working relationships with its shareholder EADS Integrated MTAD as Airbus Miltary from 15 April 2009 November 2009 Page 5
Airbus Sites & Responsibilities November 2009 Page 6
Airbus Product Line November 2009 Page 7 Number of Seats Range
Passenger and Crew Comfort Ensure passenger and crew comfort under extreme outside conditions. November 2009 Page 8
Table of contents The Airbus Company Aircraft Development Process Process Integrate, Automate, Innovate A Rigorous CFD Approach Summary November 2009 Page 9
Simulation Tools for Environmental Control Systems CFD FDDN cabin air distribution cabin CPCS CFD pressurized fuselage -13.08 Distribution Line -15.24-11.84-13.13-15.04 RC 2-14.78 RC 3 RU 1 RC 4-13.11-13.04-12.96-13.26 Galley 2r Return Line -13.28 Supply Line -13.22-13.52-13.82-10.19-13.56-12.96-13.14 Galley 2b -11.80-13.55-12.98 cockpit -11.73-13.49-12.91-11.65-13.42 Galley 1a Galley 2c DOOR 1-12.83 Galley 2l DOOR 2 galley cooling CFD CFD packs special compartments mixing unit November 2009 Page 10
Simulation & Testing in Aircraft Development Cycle Feasibility Concept Prod. Test & Cert. R & T MG 0 MG 3 MG 5 MG 7 MG 9 MG 11 MG 13 In- Service Entry into Concept Concept freeze Design freeze Entry into FAL First Flight Entry into Service Aircraft Level Aircraft Certification Route Proving Architecture Model Flight Test Ground Test Functions Level System Level Equipment Level Cabin Performance Model Flow Calibration Model Zonal Model CFD Aircraft Integration Test System Virtual Integration Integration Test Bench System Test Qualification & Equipment Test November 2009 Page 11
Table of contents The Airbus Company Aircraft Development Process Integrate, Automate, Innovate Innovate A Rigorous CFD Approach Summary November 2009 Page 12
Integrate Automate Innovate Integrate Product System integration Process Simulation as integrated part of design process Tools Fortran + Excel + MS Visio, Matlab + Star CCM,... People Multi-functional teams, skill overlap Automate Best Practices & Standarization drive automation Test Automation via Virtual Function Integration Bench Automatic Architecture Trade-Off and Optimization Innovate Capability development via internal/external expert network Simulation as enabler for truely innovative design solutions November 2009 Page 13
Example for Tool Integration: Zonal Model Overall Fuselage Flow Model (OFFM) a modular, flexible simulation zonal model of the whole aircraft fuselage used to investigate flow critical areas such as doors, galleys, special installations, seat class change in same temperature zone, asymmetric installations of monuments ventilation flows in comfort-related (odour exhaust air from cargo, galley) or safetyrelated areas (e.g. Installation of RC/O2-bottles in triangle area) November 2009 Page 14
Example for Automation: Parametric Cabin Modeler Parametric Cabin Modeler Catia V5 based tool to create meshable aircraft cabin automatically in ~ 1 hour Example of PCM user interface Example of the created cabin November 2009 Page 15
Example for Innovation: Thermal Comfort Model Thermal Comfort Model developed by R&T partner takes into account all relevant influence parameters simulates both physical & physiological reaction to inhomogeneous thermal environment relates local thermal discomfort to sensation of overall thermal comfort coupled to CFD via cosimulation validated with experiments Thermal Sensation 3 very warm 2 warm 1 slightly warm 0 neutral -1 slightly cold -2 cold -3 very cold Thermal Comfort 3 very comfortable 2 comfortable 1 just comfortable -1 just uncomfortable -2 uncomfortable -3 very uncomfortable Passenger 2, overall thermal sensation 1.0 overall thermal comfort 0.5 left leg left foot right leg right thigh right foot left thigh right hand head 3.0 2.0 1.0 0.0-1.0-2.0-3.0 chest back pelvis left arm right arm left hand left shoulder right shoulder November 2009 Page 16
Table of contents The Airbus Company Aircraft Development Process Integrate, Automate, Innovate A Rigorous A CFD Approach Summary November 2009 Page 17
CFD A Rigorous Approach Step 1: State problem Step 2: Select target quantities Step 3: State expected accuracy Step 4: Understand physical phenomena involved Step 5: Carefully specify boundary conditions Step 6: Select appropriate models & methods Step 7: Verification, Validation & Accreditation Step 8: Adequate documentation of work see also T. Wintergerste, Best Practice Guidelines, ERCOFTAC Special Interest Group on Quality and Trust in Industrial CFD, Version 1, January 2000 November 2009 Page 18
Cabin Flow Physics cabin inlet wall jet spreading rate & penetration depth unstable thermal stratification small details inhomogeneous u profile transitional Re number heat load uncertainty in thermal boundary conditions conjugate heat transfer and internal radiation free jets spreading rate & penetration depth entrainment transient interaction low Re flow impinging flows transient 3D primary and secondary vortex structures weak shear flow streamline curvature lining leaks natural convection buoyancy forces unsteadiness dado outlet pressure distribution may cause longitudinal cabin flow November 2009 Page 19
Turbulence Modeling for Heat & Mass Transfer DNS LES hybrid LES / RANS (DES, SAS, VLES) SMC, RSM advanced EVM (NLEVM, kεv 2 f, kεθ 2, thermal flux models) LEVM ad hoc modifications (add source terms, change coefficients, impose limiter, etc.) LEVM linear eddy viscosity model DES detached eddy simulation NLEVM non-linear eddy viscosity model SAS scale adaptive simulation SMC second moment closure VLES very large eddy simulation RSM reynolds stess model DNS direct numerical simulation November 2009 Page 20
CFD Process Validation & Verification building blocks Verification test case aim: identify numerical errors characterization: basic geometry and physics, analytical or highly accurate semi-empirical solutions available example: turbulent flat plate boundary layer T L = 20 C v L = 0,15 m T 22 C W = s CFD vendor responsibility Validation test case U 0 =0,445 m/s aim: identify modeling errors and model deficiencies characterization: simplified geometry and physics, boundary conditions and operating conditions very well known example: ventilated enclosure Benchmark test case H=3 m, W=3 m, L=9 m CFD vendor responsibility aim: demonstrate M&T capability for a representative configuration, calibrate method for intended application characterization: mockup geometry, detailed measurements example: A380 Upper Deck cabin mockup of DLR Göttingen Demonstration experiment aim: build up confidence for complex flows and geometries characterization: actual hardware, only few measurement data, not suited for validation example: recording of velocity and temperature at some locations during ground or flight test Industry responsibility Industry responsibility November 2009 Page 21
Scope of CFD Data Integrity & Quality Simulation validated M&T for entire design space rigorous error assessment virtual certification data traceable & reproducable virtual testing quantitative validated M&T for baseline design Accuracy compare alternative designs understand flow phenomena qualitative Colors For Directors November 2009 Page 22
Table of contents The Airbus Company Aircraft Development Process Integrate, Automate, Innovate A Rigorous CFD Approach Summary November 2009 Page 23
Summary New Airbus way of working Increasing importance of simulation for aircraft design Colors For Directors are not to be confused with credible CFD Innovation, automation and integration are key to success November 2009 Page 24
Thank you for your attention Please visit www.airbus.com for more information November 2009 Page 25
AIRBUS OPERATIONS GMBH. All rights reserved. Confidential and proprietary document. This document and all information contained herein is the sole property of AIRBUS OPERATIONS GMBH. No intellectual property rights are granted by the delivery of this document or the disclosure of its content. This document shall not be reproduced or disclosed to a third party without the express written consent of AIRBUS OPERATIONS GMBH. This document and its content shall not be used for any purpose other than that for which it is supplied. The statements made herein do not constitute an offer. They are based on the mentioned assumptions and are expressed in good faith. Where the supporting grounds for these statements are not shown, AIRBUS OPERATIONS GMBH will be pleased to explain the basis thereof. AIRBUS, its logo, A300, A310, A318, A319, A320, A321, A330, A340, A350, A380, A400M are registered trademarks. November 2009 Page 26