Overview of CIRA participation in the Clean Sky GREEN REGIONAL AIRCRAFT (GRA) ITD

Transcription

1 Overview of CIRA participation in the Clean Sky GREEN REGIONAL AIRCRAFT (GRA) ITD Greener Aeronautics Symposium University of Glasgow - 3 November 2014 Raffaele Salvatore Donelli, PhD CSJU Seconded Project Officer Centro Italiano di Ricerca Aerospaziale

2 Green Regional Aircraft ITD Forewords Clean Sky Green Regional Aircraft ITD GRA Domains New Configuration Low Weight Configuration Low Noise Configuration Partial review of CIRA contribution Overall scenario of Technologies & Demonstrations Greener Aeronautics Symposium Glasgow - 3 November

3 Transverse ITD for all vehicles The GRA ITD in the Clean Sky JTI Vehicle ITD Eco-design For Airframe and Systems Leaders: Dassault Aviation & Fraunhofer Institute Smart Fixed-Wing Aircraft Leaders: Airbus & SAAB Green Regional Aircraft Leaders: Alenia & EADS CASA Green Rotorcraft Leaders: Eurocopter & AgustaWestland Sustainable and Green Engines Leaders: Rolls- Royce & Safran Clean Sky Technology Evaluator Systems for Green Operations Leaders: Liebherr & Thales ITD: Integrated Technology Demonstrator Greener Aeronautics Symposium Glasgow - 3 November

4 The Green Regional Aircraft (GRA) ITD Regional market is a large part of Air Transport System: today, in the world, 45% of flights are operated with regional aircraft. In 2020 the share is estimated to rise to around 50%. Substantial contribution to the Clean Sky shall then come from the Regional Air Transport Improvement of the environmental impact deriving from the operation of regional aircraft are expected mainly from weight, drag and noise reduction technologies, as well as from the integration of advanced technologies belonging to other domains. Greener Aeronautics Symposium Glasgow - 3 November

5 GRA High Level Objectives To demonstrate technologies for future regional aircraft aiming at reducing: fuel consumption/pollution (CO 2 & NOx reduction) external noise ACARE Goals Ecolonomic Life Cycle Green Perfomance Aircraft Design Area pollution & fuel consumption Aerodynamics Structures&Materials Propulsion Power Requirements External noise Aerodynamics Flight Procedures Propulsion Life Cycle Materials Design Concepts Standards & Rules Greener Aeronautics Symposium Glasgow - 3 November

6 GRA High Level Work Program Achievements of environmental targets through: advanced aerodynamics and low noise design (Low Noise Configuration domain) advanced structures and materials (Low Weight Configuration domain) all electric aircraft architectures (All Electric Aircraft domain) advanced avionics architectures (Mission Trajectory Management domain) integration of these technologies in advanced aircraft configurations interfacing new power plants (New Configuration domain) Integration of technical solutions from other technology platforms of the Clean Sky (energy management and Mission & Trajectory management for SGO, engines for SAGE, Eco Design) in the Demonstrators of the Green Regional Aircraft, using a multi-disciplinary approach Greener Aeronautics Symposium Glasgow - 3 November

7 GRA ITD Top-level WBS & Links 5 Technological Domains G R A 0 M an agem en t A le n ia + E A D S C A S A G R A 1 L ow W eigh t C onfiguration Ale nia G R A 2 L ow N oise C onfiguration Ale nia G R A 3 All Electrical A ircraft Ale nia G R A 4 M ission & trajectory M an agem en t Ale nia G R A 5 N ew C onfiguration Ale nia E c o -D e s ig n IT D E D A S F W A IT D E c o -D e s ig n IT D E D S S G O IT D S G O IT D T E S A G E IT D S F W A IT D Interface btw GRA and other ITDs Greener Aeronautics Symposium Glasgow - 3 November

8 GRA ITD WBS & CIRA Contribution GRA ITD A/C Integration & technologies from other ITD s Low Weight configurations Low Noise configurations New Configurations Requirements Requirements All Electric Aircraft Technologies Technologies Mission & Trajectory Mngnt Studies and solutions Studies and solutions Wind tunnel testing Ground Demonstration Iron bird Flight Demonstration Flight Demonstration Greener Aeronautics Symposium Glasgow - 3 November

9 New Configuration (NC) Domain New Configuration Domain has the objective to design greener aircraft configurations based on the implementation of several breakthrough technologies to improve the aircraft performance in terms of both fuel consumption and noise emission. At least 5 areas, such as aerodynamics, structures and materials, control systems, and propulsion technology are subject to improvements Boundary Layer Control Active Controls Composite Structure Propulsion Technology New Airfoil Concepts Greener Aeronautics Symposium Glasgow - 3 November

10 New Configuration (NC) Domain GEARED TURBO FAN PUSHER OPEN ROTOR ADVANCED TURBOFAN LOW SPEED TURBOPROP Greener Aeronautics Symposium Glasgow - 3 November

11 NC Domain Strategy Loops The design of a green aircraft is strongly affected by the accuracy of the data and by their reliability. At this end, three different stages have been foreseen before arriving to the final aircraft design. Technology Readiness Level (TRL) TRL 1 TRL 2 TRL3 TRL 4 TRL 5 Loop 1 Loop 2 Loop 3 by increasing the reliability data Improvements estimated by Literature or/and Statistical data 3D CFD Basic Wind Tunnel Wind Tunnel T. Flight Tests Greener Aeronautics Symposium Glasgow - 3 November

12 NC Domain Loop 3 Natural Laminar flow design of the wing Polar (WT experiments WTT2) Pitch Moment (experimental estimation) High lift performance (Low WT tests WTT4) Composite Materials (2 Down selection) structural tests on large panels Weights Bench tests Benefits coming from LC&A application (WTT2 tests) Bending moment estimation Load alleviation benefits Electric System (ground Electrical Test Bench) Envisaged weight reduction Engine performance Final data from engine manufacturer Weight reduction Structures L/D Improvement Aerodynamics Systems Propulsion Fuel Consumption Noise Reduction Design of laminar GRA Aircraft Loop 3 Greener Aeronautics Symposium Glasgow - 3 November

13 Loop 2 Loop 3 NC Domain Aircraft Configurations PUSHER OPEN ROTOR LOW SPEED TURBOPROP ADVANCED TURBOFAN GEARED TURBOFAN Rear engine installation Under wing engine installation Under wing engine installation Rear & Under wing engine installation Engine data updating (AEA hypothesis) All Electric Aircraft and More Electric Aircraft Systems architecture definition Aerodynamic Improvement (Wing design and HLD studies) New materials improvement & Preliminary Structural layout definition Best configuration choice for WTT More Electric Aircraft Systems (Trade-off activities) Feasibility studies under Structural and Systems points of view Greener Aeronautics Symposium Glasgow - 3 November

14 Technology Readiness Level (TRL) Geared Turbo Fan Conf. Technological Road Map Transonic NLF Wing design WT Testing GTF A/C half-model 130 pax Aircraft configuration WTT Testing complete powered large-scale model TRL 7 TRL 6 NLF Wing Design Mach 0.74 NLF Wing Design Mach 0.78 WTT 2 WTT 5 WTT 4 TRL 5 TRL 4 GTF A/C architecture & power plant integration complete powered largescale model TRL 3 Geared Turbo Fan Configuration LOOP 2 GTF Configuration LOOP Greener Aeronautics Symposium Glasgow - 3 November

15 NC Domain CIRA Contribution Benefits Assessment, Demonstration Methodology & Strategy for GRA A/C (90&130 pax) Configurations CIRA has established the strategy for the validation & verification of the benefits at A/C level resulting from the integration of the new technologies. Green open rotor A/C CIRA has computed the Aerodynamic database of the open rotor configuration in cruise, take-off and landing conditions by means of 2D /3D analysis tools. Giovanni Andreutti Aeroacoustic analysis starting from the CFD data GRASM Mattia Barbarino Contribution to GRASM implementation (Trajectories evaluation, Databases implementation, Mission and Airport Level analysis for GTF configuration) in order to supply the TE assessment Pierluigi Iannelli Greener Aeronautics Symposium Glasgow - 3 November

16 Low Weight Configuration (LWC) - Objective Develop the most promising technologies to reduce the weight and best fitting the requirements of the Green Regional Aircraft taking into account requirements coming from other domains such as New Configuration or Low Noise Enabling Technologies Structure-Embedded Sensors to continuously control accidental damage, environment effects, and consequently in-service structural degradation. Layer, Multilayer/multi-function architectures to decrease the negative impact on weight deriving from ancillary functions requested to the structure (lightning protection, grounding, ). Nano-material technologies (nanomodified prepreg production, ). Advanced metallic structure (fully laser welded integral structure, welded applied to Titanium sheet, ). Greener Aeronautics Symposium Glasgow - 3 November

17 LWC Domain - Technologies A multifunctional single layer is a structure in which different materials are integrated - in order to assure several functions - in a way that is impossible to identify them as separate layers Multifunctional Layer Noise Damping Flame Smoke and Toxicity resistance Lightning strike Protection Impact resistance Structural property WEIGHT REDUCTION Self-healing Multifunctional Multilayer WEIGHT REDUCTION Environment barrier Self-healing Conductive A multifunctional multi-layer is a structure in which different materials are integrated, in order to absolve several functions Flame resistant Damping Greener Aeronautics Symposium Glasgow - 3 November

18 LWC Domain - Technologies Carbon nanotube strengthened epoxy resin for increased compression and interlaminar shear strength in composites (fuselage and wing) Nanomaterials Nanotubes Sensors: Fiber Optic Bragg Grating (FOBG) BRAGG GRATING FIBER OPTIC TERMINATION Cobonded J-spar with embedded FOBG sensors Monitoring events occurring to aircraft during its operation through sensors embedded in the structure for damage detection, life management, and repair and maintenance actions Greener Aeronautics Symposium Glasgow - 3 November

19 LWC Domain Development Plan JTI GRA LWC Development Research and Technologies acquisition Requirement & Architectures Technologies Development Application Studies Demonstrators Yo Y3 Y7 First Down Selection Second Down Selection After the selection of the most interesting technologies, theoretical and esperimental investigations have been carried out. Based on these results, only the most promising technologies were selected for further and deeper analysis. The enabling technologies have been selected by two down selections. First Down Selection, at a given date, based on numerical studies and basic ground testing on small/medium panels Second Down Selection based on ground testing and large panels Greener Aeronautics Symposium Glasgow - 3 November

20 LWC Domain First Down Selection TRL 3 Coupons tests TRL Fibre Optics - FOBG 2 - Fibre Optics - FOBR OBR 3 - Fibre Optics - FOBR DSS 4 - Acoustic Ultrasound AU-BB 5 - Acoustic Ultrasound EMI 6 - Lamb waves 7 - Guided waves 8 - AE-AU active and passive methods 9 - Wireless Sensors 10 - Prepreg with metallic wires interwoven 11 - Prepreg cocured with metallic mesh 1 st Down Selection 12/05/ Prepreg with thermoplastic layer cocured with microwave 13 - Prepreg with damping layer 14 - Monolithic laminates with acoustic damping material inserted 15 - Sandwich with acoustic core 16 - Prepreg nanocharged 17 - Nanomaterial for electromagnetic protection 18 - Nano-modifed resin for liquid infusion 19 - Nano-materials for innovative ice protection systems 20 - Al Li Laser welded 21 - Repair & Maintenance 1 - Fibre Optics - FOBG 2 - Fibre Optics - FOBR OBR 4 - Acoustic Ultrasound AU-BB 6 - Lamb waves 7 - Guided waves 8 - AE-AU active and passive methods 9 - Wireless Sensors 12 - Prepreg with thermoplastic layer cocured with microwave 13 - Prepreg with damping layer 14 - Monolithic laminates with acoustic damping material inserted 15 - Sandwich with acoustic core 17 - Nanomaterial for electromagnetic protection 18 - Nano-modified resin for liquid infusion 19 - Nano-materials for innovative ice protection systems 20 - Al Li Laser welded 21 - Repair & Maintenance 22 new Liquid Infusion Total: 21 Technologies 1 st Down Selection Total: Technologies Greener Aeronautics Symposium Glasgow - 3 November

21 LWC Domain First Down Selection Objective: to demonstrate the applicability of advanced CFRP, metallic alloys & process and structural health monitoring systems to achieve the expected structural weight reduction for Regional A/C TRL 3 TRL 4 TRL 5 TRL Concepts Studies 1 Down Selection 2 Down Selection Specimens / Coupons Coupons and large panels tests activities Flat large panels Panel to be replaced Flight Demo Technologies development: req s, design, manufacturing, assembly & test Full Scale Ground Demo Cockpit Ground Demo Wing Box Ground Demo Fuselage Ground Demo Greener Aeronautics Symposium Glasgow - 3 November

22 LWC Domain CIRA Contribution Fibre Optics - FOBG - (tests on coupons sensorised with fibre optic sensors) Prepreg with metallic wires interwoven (tests on Prepreg with metallic wires interwoven coupons) Prepreg nanocharged (tests on Nano-reinforced resins coupons) Wing & Fuselage flat large panels design criteria Report on NDI results on composite flat large panels in Pre-Preg. Project under Call for Proposals: composite panels with nanofiller dispersed in resin manufacturing and testing. Stefania Cantoni (s.cantoni@cirait) Umberto Mercurio (u.mercurio@cira.it) Greener Aeronautics Symposium Glasgow - 3 November

23 LWC Domain CIRA Contribution Fibre Optics - FOBG - (tests on coupons sensorised with fibre optic sensors) Testing of the composite panel with embedded FOBG Design and realization of the test rig Test execution The gap between the frames and the lower plates allows a displacement in compression of 10 mm Durability Test Repeatability test Break Test Greener Aeronautics Symposium Glasgow - 3 November

24 LWC Domain CIRA Contribution Panels configuration 2 optical fibers (identified with the letters A and B) are embedded in each panel, angled at 45 with the load axis Each optical fiber has 3 Bragg gratings 2 strain gages are aligned with each Bragg grating on the front side of the panel 1 strain gage is aligned with each Bragg grating on the back side of the panel 2 additional strain gages are placed at the midline of the panel, aligned with the load axis SGB1L FOBG SGB1R Greener Aeronautics Symposium Glasgow - 3 November

25 Low Noise Configuration (LNC) Domain Aknowledgements Some of following slides are courtesy of Michele Averardo (Alenia Aermacchi) as Responsible for Low Noise Configuration Domain of the GRA ITD Many thanks also to the whole GRA Alenia Team Greener Aeronautics Symposium Glasgow - 3 November

26 LNC Domain Toward ACARE targets To meet the targets stated by the Clean Sky JTI toward a drastic reduction of the environmental impact by future civil air transport, the GRA ITD LNC domain is addressed to breakthrough technologies as Advanced Aerodynamics, Load Control & Alleviation and Low Airframe Noise, tailored to 130-seat & 90-seat Green Regional Aircraft. Greener Aeronautics Symposium Glasgow - 3 November

27 LNC Domain Toward ACARE targets To meet the targets stated by the Clean Sky JTI toward a drastic reduction of the environmental impact by future civil air transport, the GRA ITD LNC domain is addressed to breakthrough technologies as Advanced Aerodynamics, Load Control & Alleviation and Low Airframe Noise, tailored to 130-seat & 90-seat Green Regional Aircraft. Such technologies are aimed to: Enhance aerodynamic efficiency in the whole flight envelope, so as to reduce fuel burnt / air pollutant emissions Prevent aerodynamic loading from exceeding given limits at critical (gust & manoeuvre) conditions for wing structural weight saving Reduce A/C acoustic impact in approach/ landing phases Greener Aeronautics Symposium Glasgow - 3 November

28 LNC Domain Toward ACARE targets Main Technical Solutions investigated Mainstream Technologies Natural Laminar Flow To reduce skin friction drag High Aspect Ratio Wing & Winglets To reduce induced drag Wing Optimised Aerodynamics Active control of wing movables To optimise span load distribution (induced drag reduction) in off-design conditions To reduce wing bending and torsion from gust & manoeuvre loads Wing Aeroelastic Tailoring Passive reduction of bending moment Load Control Load Alleviation Conventional & Innovative Architectures Krueger, Basic Flap, Morphing Flap, Droop Nose Low-Noise concepts Liners, Fences High-Lift Devices Aerodynamic Fairings Strut covers, wheel rim caps Bay cavity acoustic treatments Liners / Sound absorbers Low-Noise Landing Gears Greener Aeronautics Symposium Glasgow - 3 November

29 LNC - Technologies Maturation Road Map Today Achievements (TRL 4) Technologies developed on a multi-disciplinary basis (aerodynamics, aeroacoustics, structures, systems) through CFD/CAA/CSM methods and CAD/CAE modelling, validated (when applicable) by 2D WT Tests and laboratory experiments on small mechanical prototypes, and integrated at A/C concept level. Greener Aeronautics Symposium Glasgow - 3 November

30 LNC - Technologies Maturation Road Map Next Step (TRL 5) Technologies demonstrations in a realistic experimental environment, through large-scale WT models and full-scale mechanical prototypes. Greener Aeronautics Symposium Glasgow - 3 November

31 LNC Domain 130-seat Aircraft The 130-seat Green Regional A/C (Mach 0.74) is a rear-mounted twin-engines Geared Turbo Fan configuration with Natural Laminar Flow Wing. Conditions: Mach = 0.74 Reynolds = 21.2 millions Ref. Length = X m Wing Area = X m 2 (half model) Lift coefficient (WB) = fixed Wing Lift coefficient = fixed Grid size ~ 7 millions cells 136 Blocks Zonal approach: Fuselage Euler flow (no viscous drag) Wing RANS flow Greener Aeronautics Symposium Glasgow - 3 November

32 Low Noise Configuration (LNC) - CIRA Requirements for CIRA Laminar Wing Design Objectives: Minimize the total drag coefficient (target = L/D>18) Maximize the transition position Constraints: X 1 < C L < X 2 C M > X Fuel tank volume Design variables: Angle of attack [1 : 2 ] 3 piecewise linear twist variables distributed along span, centered respectively on root, crank and tip sections 2 piecewise linear section shape variables Greener Aeronautics Symposium Glasgow - 3 November

33 CIRA Wing Design Procedure MOGA optimizer (GAW) Design Variables Geo modeler (GEORUN) Wing geometry Wing-body intersection Domain modeler/mesh generator (ENDOMO/ENGRID) GRID Flow solver (ZEN) BL analysis (BL3D) BL stability (PARAB) Objective/constraints Domenico Quagliarella, Emiliano Iuliano, Raffaele S. Donelli Greener Aeronautics Symposium Glasgow - 3 November

34 CIRA Wing Design Procedure J. Perraud, D. Arnal, G. Casalis, J. Archambaud, R. S. Donelli, Automatic Transition Prediction using Simplified Methods, AIAA Journal, Vol. 47, No. 11, November 2009 Flow solver (ZEN) + BL analysis (BL3D) Feedback (second order effect) Using the database method, the influence of N factor variation on turbulent to laminar flow transition can be evaluated with little computational effort Transition line d.quagliarella@cira.it e.iuliano@cira.it r.donelli@cira.it BL stability (PARAB) N factor value Greener Aeronautics Symposium Glasgow - 3 November

35 CIRA Optimized Wing-Body Greener Aeronautics Symposium Glasgow - 3 November

36 CIRA Optimized Wing-Body Airfoil Geometries and pressure coefficient distributions along the span Ubaldo Cella, Domenico Quagliarella, Raffaele Donelli, Biagio Imperatore, Design and Test of the UW-5006 Transonic Natural-Laminar-Flow Wing, JOURNAL OF AIRCRAFT Vol. 47, No. 3, May June 2010, DOI: / E. Iuliano, D. Quagliarella, R.S. Donelli, I.S. El Din, D. Arnal, Design of a Supersonic Natural Laminar Flow Wing-Body, JOURNAL OF AIRCRAFT Vol. 48, No. 4, July August 2011, DOI: /1.C Greener Aeronautics Symposium Glasgow - 3 November

37 CIRA Optimized Wing-Body Global Design point CL = X Wing pressure C D = 100 dc Wing friction C D = 30 dc Body friction C D 80 dc (estimated) Total drag = 210 dc L/D = 24.7 AOA = 1.2 CM = X Transition lines for Ncrit = 15 (conservative approach) Greener Aeronautics Symposium Glasgow - 3 November

38 CIRA Transition Prediction Methods Bl Codes BLQ3D 3C3D Stability Codes Nolli Cosal Raffaele S. Donelli Donato de Rosa Greener Aeronautics Symposium Glasgow - 3 November

39 CIRA Transition Prediction Algorithm 3D Euler/RANS CFD Velocity field Check for attachment line instability, Poll criterion R 245 3D FD compressible boundary layer BL Integral quantities d, d *, q, H Velocity, temperature BL profiles Nolli Cosal Database method Transition position e N method N critical choice TS CF Envelope N factor curves Greener Aeronautics Symposium Glasgow - 3 November

40 LNC Domain High Lift Devices Various HLD architectures were assessed accounting for aerodynamic performances and acoustic impact (from 3D CFD/CAA analyses and 2D WT tests), as well as for feasibility and complexity of the actuation system, through virtual (CAD/CAE) kinematics modelling and, in some cases, preliminary mechanical tests. The first two were: Double-slotted Flap by ALA - Two-element, Fowler-type T/E device, as benchmark of other HLD configurations. Single-slotted Flap by PAI - Single-element full-fowler T/E device, conceived as an alternative less-noise solution with respect to the baseline double-slotted flap. As typically found on laminar wings, poor high-lift performance (C Lmax, α STALL ) resulted from 3D CFD analyses with flap only configurations, due to early (α 7 ) L/E flow separation. Therefore, in order to meet A/C low-speed requirements (approach speed and attitude at landing), combined L/E and T/E high-lift devices had to be considered. In doing so, both conventional and innovative low-noise solutions were also investigated. 3D CFD FLOW SEPARATION Greener Aeronautics Symposium Glasgow - 3 November

41 LNC Domain High Lift Devices Several HLD concepts have been studied on a multi-disciplinary basis, accounting for aerodynamic and acoustic performances, structural and system issues, etc. The attention was mainly focused on High Lift Technologies providing higher aerodynamic performances without/minimizing penalties in noise emissions. High Lift Technologies having higher acoustic performances without penalties in aerodynamic Lined Flap Morphed Flap Fences Kruger Slat Greener Aeronautics Symposium Glasgow - 3 November

42 CIRA Liner Flap Design Concept The main differences between a standard flap and a lined flap are the presence of a micro-perforation on the external facing sheet and an additional honeycomb layer inside the flap. The cavities generated by the micro holes and the honeycomb behave as Helmholtz resonators resulting in a sound-absorbing effect. A 1DoF liner consists of single layer sandwich with a solid back-plate, a micro-perforated facesheet and a honeycomb core. The concept can be extended to a 2DoF liner by adding a second honeycomb core separated by a porous septum Mattia Barbarino & Damiano Casalino m.barbarino@cira.it Greener Aeronautics Symposium Glasgow - 3 November

43 CIRA Liner Flap 2D CFD/WT Testing A sensible noise reduction ( OASPL 6dB) with respect to the baseline flap was predicted by 2D CFD/CAA analyses. Such a very promising result was partially confirmed by 2D WT Tests. OASPL Contour Plot: baseline flap lined flap Antonello Marino a.marino@cira.it & Ignazio Dimino i.dimino@cira.it Greener Aeronautics Symposium Glasgow - 3 November

44 CIRA Liner Flap 2D CFD/WT Testing 2D WTT have confirmed the effectiveness of this lownoise design (red line) against the baseline flap ΔOASPL 2-4dB SPLdB Baseline Flap Lined Flap 2D WTT f (Hz) Originally designed for the flap of the TP 90-seat A/C, this concept has been later on tuned also to the flap of the GTF 130-seat A/C WT model (ESICAPIA). Antonello Marino a.marino@cira.it & Ignazio Dimino i.dimino@cira.it Greener Aeronautics Symposium Glasgow - 3 November

45 CIRA Krueger Flap Design Concept Krueger Slat by CIRA - L/E device designed to greatly enhance, combined with T/E flap, the wing high-lift performance, so as to meet A/C low-speed requirements, still preserving laminar flow on the wing upper side. Very good high-lift performances were predicted by 3D CFD analyses, confirmed by 2D WT tests, showing the ability of this device to delay wing stall up to large angles of attack ( 13 deg), with a consequent significant C Lmax increase ( 0.5) wrt other HLD configurations. SKIN POST-STALL = 14 The original designs of Krueger and T/E single-slotted flap were tailored by ALA to the final GTF 130-seat A/C aerodynamic model; relevant 3D CFD analyses in landing configuration confirmed previous results, so as the A/C low-speed requirements were fully met. This architecture is the basic HLD geometry brought to the final WT demonstration on the complete A/C powered model (ESICAPIA). FLOW SEPARATION 3D CFD Greener Aeronautics Symposium Glasgow - 3 November

46 CIRA Krueger Flap 3D optimization Automatic 3D flap shape-modification/positioning & droop spoiler rotation Automatic 3D Krueger shape-modification/positioning Parametric CFD mesh (4 Mcells) CFD Analysis of initial configuration (flap separation) Minimized flap separation after some steps of optimization Greener Aeronautics Symposium Glasgow - 3 November

47 CIRA Krueger Flap 2D WT Tests Krueger Slat + Single-Slotted Flap Aerodynamic Impact As expected, 2D WTT confirmed numerical analysis. Large increase in CLmax ( 0.5) wrt other HLD and delay of the wing stall to high angles of attack ( 13 ) Noise Impact From 2D WT tests the airframe noise spectra result comparable, neglecting the peak at high frequency, to those of the baseline HLD geometry SPLdB Krueger + S-S flap baseline S flap f (Hz) Greener Aeronautics Symposium Glasgow - 3 November

48 CIRA Fences Design Concept Reduction of flap side-edge vortex intensity and shear stresses: Flap side-edge noise reduction Fence type A Fence type B Fence type C Greener Aeronautics Symposium Glasgow - 3 November

49 CIRA Fence for Flap CFD/CAA GRID FEATURES NO FENCES WITH FENCES CELLS NUMBER ~1.60e+07 ~2.20e+07 TYPOLOGY UNSTRUCTURED UNSTRUCTURED grid particular vortical flow structure side edge particular Greener Aeronautics Symposium Glasgow - 3 November

50 CIRA Fence for Flap CFD/CAA grid particular baseline side-edge fence Contour plots of the turbulent kinetic energy for 2D sections extracted from the aerodynamic field of both baseline and side-edge fence configurations. Greener Aeronautics Symposium Glasgow - 3 November

51 CIRA Fence for Flap CAA Results The slotted fence reduces the noise efficiently (6-8dB). Though slightly high noise appears among the frequencies up to 50 Hz. Downwards microphone, 270 o, 500m Greener Aeronautics Symposium Glasgow - 3 November

52 CIRA Fence for Flap 2D WT Tests Reference 00 Fence A Fence B Fence C C7A C7B C7C Single slotted flap without fence (C70) Greener Aeronautics Symposium Glasgow - 3 November

53 CIRA Fence for Flap 2D WT Tests Greener Aeronautics Symposium Glasgow - 3 November

54 CIRA Fence for Flap Conclusions Noise reduction detected from 2D WTT; noise sources localization revealed fence effectiveness in reducing flap tip vortex intensity. with FENCE w/o FENCE 2D WTT - SPL Device applied to the GTF 130-seat A/C WT model (ESICAPIA). Greener Aeronautics Symposium Glasgow - 3 November

55 CIRA Morphed Flap Design Concept Morphing Flap: Novel wing T/E device conceived to match a given target shape, as an aerodynamically optimised cambered flap. Two architectures have been developed: DESA Flap by CIRA - Deeply Embedded Smart Actuators architecture, constituted by elastic cells connected each other in a serial way along the flap chord; SMA actuators contraction causes the relative rotation of the rib components. 2D Prototype SACM Flap by UniNA - Smart Actuated Compliant Mechanism architecture, made up of articulated ribs structure, actuated by an electric motor, enabling dual-morphing capability: The morphed shape (mode #1) will be tested on the complete A/C WT model (ESICAPIA). Mode #1 2D Prototype Mode #1: adaptive flap camber (T-Off / Landing) Mode #2: load control tab (flap stowed) Mechanical demo will be performed on a 1:1 (3.6m span) prototype sized to the half (inner part) of the outboard flap Greener Aeronautics Symposium Glasgow - 3 November

56 cl CIRA Morphed Flap Design Concept Optimized morphed flap geometry by CFD 3,5 3,4 baseline best 3,3 3,2 3,1 3 2,9 2,8 2, alfa Mechanical Concept Greener Aeronautics Symposium Glasgow - 3 November

57 CIRA Morphed Flap Prototype A mechanical prototype of a fullsize segment of the outboard flap has been manufactured and successfully tested demonstrating the functionality and ability of the morphing flap structure to match the target shape, while withstanding simulated aerodynamic loads. Greener Aeronautics Symposium Glasgow - 3 November

58 CIRA Morphed Flap Prototype Greener Aeronautics Symposium Glasgow - 3 November

59 CIRA Morphed Flap 2D WT Results Aerodynamic Impact Results of 2D WT tests Vs numerical show an increment in CL max ( 0.4) wrt the original single-slotted flap. Nevertheless, the high-lift requirements are not fully met because of low stalling angle. Noise Impact the difference in terms of airframe noise between original single-slotted (blue curve) and morphed (red curve) flap shapes is negligible Morphed Single Slot SPLdB Morphed flap Morphed Flap S-S flap f (Hz) Greener Aeronautics Symposium Glasgow - 3 November

60 GRA Nose & Main Landing Gear Main Landing Gear Nose Landing Gear The first step was the design of MLG and NLG baseline architectures, jointly carried out by ALA and MBD. Greener Aeronautics Symposium Glasgow - 3 November

61 CIRA Nose & Main Landing Gear The second step was the development of low-noise concepts, by GRA Members and Partners of projects ALLEGRA, CALAS & NOISETTE, through numerical studies (empirical predictions and CFD/CAA analyses) and basic WT Tests as well. The feasibility of relevant solutions was assessed by ALA & MBD and some modifications were applied, when necessary. The NLG down-selected concepts were: #N1 Spoiler by NOISETTE #N2 Wheels wind-shield by NOISETTE #N3 Wheels hub-caps by FHG #N4 Perforated fairings by ALLEGRA Greener Aeronautics Symposium Glasgow - 3 November

62 CIRA Nose & Main Landing Gear Sea-level free-stream conditions Vinf = 70 m/s Pinf = KPa Tinf = 288 K Without bay door Francesco Capizzano (f.capizzano@cira.it ) With bay door Greener Aeronautics Symposium Glasgow - 3 November

63 CIRA Nose & Main Landing Gear Francesco Capizzano ) Greener Aeronautics Symposium Glasgow - 3 November

64 CIRA Landing Gear Acoustic devices 3. Fairing design The CIRA fairing proposal consists of two separated covers that has been designed by complying with the preliminary considerations, the bay geometrical constraints and by not interfering with LG kinematics. Cover applied on the main leg and on the absorber Reduce high frequency of the smaller parts; Reduce interactions between main leg and absorber. Hole cap applied on the leg joint Attenuate the hole cavity tone. Rough estimation of the noise reduction ΔdB = 10log(1-Sf) ~ 3dB Sf (fairing surface/lg surface) A draw-back of the classical fairing is that the high speed flow deflection onto other components and fairing itself can introduce additional noise sources. Making the fairing porous can lead to an additional noise decrease. Porosity of about 40% is the right trade-off Greener Aeronautics Symposium Glasgow - 3 November

65 Bay and Door Liners The device proposed consist of a set of absorber materials applied on the fuselage at the aim of dissipating acoustic energy (bay and door). Acoustic liners are sandwich materials that consist of honeycomb closed by two sheet layers. The facing-sheet is micro-perforated. Honeycomb CIRA Landing Gear Acoustic devices Solid back-plate Liners can be tailored to dissipate acoustic energy at certain frequencies by changing the liner manufacturing characteristics. The radiation characteristics of the liner is defined by the acoustic impedance Z. Porous septum 1DoF Honeycomb 2DoF Solid back-plate Porous face sheet h h 1 h 2 Honeycomb Porous septum Honeycomb Porous Solid back-plate face sheet h 1 Porous septum h Greener Aeronautics 1 Symposium Glasgow - 3 November h

66 CIRA Landing Gear Acoustic devices CFD/CAA performed have showed that the preliminary set of liner parameters for the frequency of 300 Hz exhibits a modified SPL directivity with an averaged SPL reduction of 1.3dB Greener Aeronautics Symposium Glasgow - 3 November

67 GRA Nose & Main Landing Gear ALLEGRA Project Tests on fulls cale Nose Landing Gear Tests on Main Landing Gear scale 1:2 Nose Landing Gear In PininFarina WT Greener Aeronautics Symposium Glasgow - 3 November

68 Other CIRA Activities Synthetic Jet Simulation Wind Tunnel Investigations on gap/step/roughness effects on laminar flow Drag Reduction (3D micro-riblets) RANS solver development for open rotor simulations Greener Aeronautics Symposium Glasgow - 3 November

69 LNC Technologies & Demonstrations GRA 130-seat WTT2 - NLF wind tunnel test investigation (high speed) WTT8 - Gust Load Alleviation wind tunnel test investigation GT1 GT2 GT3 - Load Alleviation Control System ground demo - 3D Morphing Flap ground demo - Droop Nose mechanics demo WTT4 - A/C low-speed WT demo (aerodynamics performance) WTT5 - A/C low-speed WT demo (aero-acoustic performance) Greener Aeronautics Symposium Glasgow - 3 November

70 LNC Technologies & Demonstrations Natural Laminar Flow Wing Optimised aerodynamic design (pressure distribution), allowing extended laminar flow, to reduce skin friction drag in cruise (M 0.74, C L = 0.5): L/D (wing-body) 24.5 Status: CFD analyses TRL 4 by ONERA, ALA Load Control (by ALA, CIRA, PoliTo) Optimised span load distributions through differential deflection of T/E devices (small tabs, split ailerons) to enhance aerodynamic efficiency and to reduce static loads in off-design conditions: 4 7% L/D increase for 500nm mission. Status: CFD/CSM aero-elastic analyses - TRL 4 NLF Wing WT demo Target: TRL 5 ETRIOLLA (CfP) In progress: presented today TESTS (January 2015) Laminar Flow extent in cruise (M 0.74) and off-design conditions (M ) at high Reynolds number LC devices effectiveness in reducing induced drag and bending moment in steady conditions at different points (M, C L ) of the flight envelope (climb, descent) WT MODEL (Mechanical Design completed) 1:3 (5.7m span) half-wing flexible model reproducing the full-size wing deformation (bending and torsion) under static loads TEST SECTION #1 Ø 8 m, Mach 1.0 WIND TUNNEL ONERA S1MA Greener Aeronautics Symposium Glasgow - 3 November

71 LNC Technologies & Demonstrations Natural Laminar Flow Wing Optimised aerodynamic design (pressure distribution), allowing extended laminar flow, to reduce skin friction drag in cruise (M 0.74, C L = 0.5): L/D (wing-body) 24.5 Status: CFD analyses TRL 4 by ONERA, CIRA, ALA Load Control (by ALA, CIRA, PoliTo) Optimised span load distributions through differential deflection of T/E devices (small tabs, split ailerons) to enhance aerodynamic efficiency and to reduce static loads in off-design conditions: 4 7% L/D increase for 500nm mission. Status: CFD/CSM aero-elastic analyses - TRL 4 NLF Wing WT demo Target: TRL 5 ETRIOLLA (CfP) In progress: presented today TESTS (January 2015) Laminar Flow extent in cruise (M 0.74) and off-design conditions (M ) at high Reynolds number LC devices effectiveness in reducing induced drag and bending moment in steady conditions at different points (M, C L ) of the flight envelope (climb, descent) WT MODEL (Mechanical Design completed) 1:3 (5.7m span) half-wing flexible model reproducing the full-size wing deformation (bending and torsion) under static loads TEST SECTION #1 Ø 8 m, Mach 1.0 WIND TUNNEL ONERA S1MA Greener Aeronautics Symposium Glasgow - 3 November

72 LNC Technologies & Demonstrations Load Alleviation (ALA, CIRA, PoliTo) Wing box torsional stiffness tailored to spanwise lift distribution minimising wing root bending moment (-8% at Nz = 2.5 MTOW) passive LA - for wing structural weight saving (13%) Reduction of dynamic loads from gust encounter and manoeuvre by active (feedforward + feedback) control of ailerons and elevator, e.g.: 25-chord gust bending load first peak reduced by 32% Status: aero-servo-elastic virtual A/C model coupling aero-elastic and flight mechanics models, sensors & actuators models and control laws - TRL 4 Gust Load Alleviation WT demo GLAMOUR (CfP) - In progress TESTS (September 2015) Viability of the LA system (control laws, devices and sensors) coupled with the wing structural response under gust excitation WT MODEL 1:6 ( 2.5m span) half-a/c aero-servo-elastic model with: flexible wing reproducing the full-size wing dynamic behaviour active gust LA devices sensors & actuators control laws engineering model in the loop WIND TUNNEL Politecnico of Milan with gust generator system at proper scaled frequencies WT TEST SECTION 3 4 m, Mach 0.2 Target: TRL 5 Greener Aeronautics Symposium Glasgow - 3 November

73 Load at Wing Root LNC Technologies & Demonstrations Load Alleviation (ALA, CIRA, PoliTo) Wing box torsional stiffness tailored to spanwise lift distribution minimising wing root bending moment (-8% at Nz = 2.5 MTOW) passive LA - for wing structural weight saving (13%) Reduction of dynamic loads from gust encounter and manoeuvre by active (feedforward + feedback) control of ailerons and elevator, e.g.: 25-chord gust bending load first peak 1.0E E E E E+06 reduced by 32% -1.5E+06 Status: aero-servo-elastic 5.47E E E+06 JTI/GRA - GTF - ASSESSMENT OF FEED FORWARD & L1 CONTROL Mx [Nm] at Wing Root (WS21) - ZFW - 25 Chords -2.0E+06 0 virtual A/C model coupling Time [s] aero-elastic and flight mechanics models, sensors & actuators models and control laws - TRL E+05 Load Alleviation Control System ground demo By ALA - Going to start Target: TRL 5 TEST RIG FEATURES & TESTS (October 2015) Realistic system (sensors, real-time computer, control laws and actuators) inserted in a simulated HW/SW operational environment. A key feature of the test rig will be the high dynamic capabilities, in order to verify and validate the performances of the LA control chain composed by sensors, computing and actuation faster than conventional A/C control systems. Aim of the tests is to verify that the transfer functions, from sensors to computers and Closed Loop - OPT21 Open Loop - OPT21 to actuators, correspond to Low pass filter Control Law the specified requirements and so validate the simulations performed to define the load control and alleviation strategy. L1 Adaptive Controller State predictor Adaptive Law d a d e Actuator Model d a,eff d e,eff Aircraft Aeroelastic Model probe FeedForward Adaptive Controller - + Greener Aeronautics Symposium Glasgow - 3 November

74 LNC Technologies & Demonstrations High-Lift Devices #1 L/E Krueger Slat + T/E Flap (by CIRA,ALA) Morphed Flap (see next slide) Lined Flap (by CIRA) Aerodynamic and Aero-acoustic 2D WT Tests 3D CFD Analyses (Wing-Body-Tail-HLD) M 0.2, Landing: C L max 2.7, α STALL 14 Morphed Flap: C L max > 0.1 A/C low-speed WT demo Target: TRL 5 ESICAPIA (CfP) - In progress: presented today EASIER (CfP) - Going to start TESTS (May July 2015) A/C aerodynamic S&C in takeoff and landing (M 0.20) A/C acoustic impact and HLD low-noise solutions WT MODEL 1:7 A/C powered model with HLD and control movables WIND TUNNEL RUAG LWTE 7 5 m TEST SECTION M 0.2 Status: TRL 4 Greener Aeronautics Symposium Glasgow - 3 November

75 LNC Technologies & Demonstrations High-Lift Devices #2 Morphing Flap SACM (by UniNA) Novel architecture, based on Smart Actuated Compliant Mechanism, driving articulated finger-like ribs, conceived to enable controlled wing camber, both in takeoff/ landing as high-lift device (morphed flap) and in cruise (flap stowed) as load control tab. Tests on 2D mechanical prototype (60 80 cm) 3D design sized to inner half-part (3.6m span) of the outboard flap 3D Morphing Flap ground demo By UniNA - In progress: presented today TESTS (July 2015) Ground Vibration Tests Functionality tests to assess dual-morphing capability with/without simulated aerodynamic loads Static Tests under limit loads TEST ARTICLE (Mechanical Design completed) Morphing flap tapered (3.6m span) full-scale Mechanical prototype Target: TRL 5 Status: TRL 4 Greener Aeronautics Symposium Glasgow - 3 November

76 LNC Technologies & Demonstrations High-Lift Devices #3 Droop Nose (by Fraunhofer) L/E device with smart actuation based on external actuator and rotating lever mechanism connected to front stringers to transmit forces to the skin. SMA patches on the lower surface contribute to skin cambering and prevent from skin buckling. 1 st design ( ) - twisted Droop Nose: from 10 I/B (18% span) to 0 O/B (67% span) DISCARDED (HLD down-selection, D ) due to bad high-lift performance from CFD. 2 nd design ( ) full-span Droop Nose twisted: from 15 (18% span) to 0 (98% span) constant 15 deflection Good results from CFD Status: TRL 3 Droop Nose WT demo Target: TRL 4 By Fraunhofer - In progress: presented today WT MODELS 1:6 half-wing modular WT model to test high-lift configurations with T/E flap, with/ without droop nose Half-wing (clean geometry) WT model at same scale FACILITY Automotive Weissach WT Nozzle exit: 22 m 2 Mach 0.19 TESTS (Sept. 2014) Aerodynamic assessment (high-lift performance and stall onset), Mach 0.2 Aero-acoustic impact (noise sources localization and overall Sound Pressure Level) Greener Aeronautics Symposium Glasgow - 3 November

77 LNC Technologies & Demonstrations High-Lift Devices #3 Droop Nose (by Fraunhofer) L/E device with smart actuation based on external actuator and rotating lever mechanism connected to front stringers to transmit forces to the skin. SMA patches on the lower surface contribute to skin cambering and prevent from skin buckling. 1 st design ( ) - twisted Droop Nose: from 10 I/B (18% span) to 0 O/B (67% span) DISCARDED (HLD down-selection, D ) due to bad high-lift performance from CFD. 2 nd design ( ) full-span Droop Nose twisted: from 15 (18% span) to 0 (98% span) constant 15 deflection Good results from CFD Status: TRL 3 Droop Nose ground demo Target: TRL 4/5 By Fraunhofer - In progress: presented today TEST ARTICLE (Mechanical Design completed) Full-scale (3m span wing segment) carbon fibre composite structure mechanical prototype, as a technology platform integrating: DN actuation system and kinematics CNT-based ice protection system Synthetic Jets actuators TESTS (August 2014) DN actuation performance (target deflection w/o skin buckling or wavy deformation) Icing protection system under droop nose deflection and SJ actuators combined functionality (with simulated icing conditions in Wind Tunnel) Greener Aeronautics Symposium Glasgow - 3 November

78 LNC Technologies & Demonstrations WTT2 NLF Wing and LC devices high-speed performances WTT8 GT1 GT2 GT3 WTT4 D E M O N S T R A T I O N S Gust Load Alleviation Strategy Gust Load Alleviation Control System Morphing Flap mechanics Droop Nose mechanics Droop Nose aerodynamics A/C low-speed aerodynamic performance WTT5 A/C acoustic impact ETRIOLLA IN PROGRESS Half-Wing flexible 1:3 WT model GLAMOUR IN PROGRESS Half A/C aeroservo elastic 1:7 WT model LC&A System Test Rig Morphing Flap Prototype Droop Nose Prototype Droop Nose Wing 1:6 WT Model ESICAPIA IN PROGRESS D E M O N S T R A T O R S EASIER NEXT START A/C powered 1:7 WT model T E C H N O L O G I E S NLF Wing Load Control & Alleviation High-Lift Devices Greener Aeronautics Symposium Glasgow - 3 November

79 LNC Technologies & Demonstrations Thank You! Greener Aeronautics Symposium Glasgow - 3 November