Kevin Nicholls, EIVW Prepared by Heinz Hansen TOP-LDA ... · filler cover . DLR . floating joint ....

NLF Slat on A320 Quick Technology Evaluation (Performance only)

Programme Discussions Kevin Nicholls, EIVW

Laminarität für zukünftige Verkehrsflugzeuge Überblick, Anforderungen und Status Ergebnisse des AirbusTechnologieprogramms Low Drag Aircraft (TOP-LDA)

Wissenschaftstag Braunschweig 2015 Prepared by Heinz Hansen

TOP-LDA Leader, ETEA Presented by Bernhard Schlipf, ESCRWG

© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document.

© A

IRB

US

S.A

.S. A

ll rig

hts

rese

rved

. Con

fiden

tial a

nd p

ropr

ieta

ry d

ocum

ent.

Content TOP-LDA Vortrag Wissenschaftstag Braunschweig 7. Oktober 2015

2 Requirements and selected Approach

3 Structure Concepts Status

1 TOP LDA Introduction & Overview

4 Manufacturing and Flight Test Demonstration

5 Summary & Outlook


© A

IRB

US

S.A

.S. A

ll rig

hts

rese

rved

. Con

fiden

tial a

nd p

ropr

ieta

ry d

ocum

ent.

Content





5 Summary & Outlook

TOP-LDA Vortrag Wissenschaftstag Braunschweig 7. Oktober 2015


© A

IRB

US

S.A

.S. A

ll rig

hts

rese

rved

. Con

fiden

tial a

nd p

ropr

ieta

ry d

ocum

ent.

0 $

1 $

2 $

3 $

4 $

5 $

Jan. 90 Jan. 94 Jan. 98 Jan. 02 Jan. 06 Jan. 10 Jan. 14

Jet Fuel Price as Driver for Performance Improvement

Source: US Energy Information Administration, 9 November 2012

1990-2001 average 59 ct / gal

12 Sep 2008 4.81 $ / gal

First gulf war Second gulf war

11 Sep 2001

15 Sep 2008 Lehman Brothers

first major Airbus laminar R&T

activities

Jet fuel price

restart of Airbus laminar R&T activities

Drag reduction (by laminar flow) and efficient engines are key elements for reduction of fuel consumption



© A

IRB

US

S.A

.S. A

ll rig

hts

rese

rved

. Con

fiden

tial a

nd p

ropr

ieta

ry d

ocum

ent.

What is laminar flow?

V = 0 Aircraft surface

Schematic Representation of Boundary Layer Skin friction coefficient

Laminar flow can reduce friction drag significantly Friction drag contributes to total a/c drag with ≈ 50% Biggest contributor to friction drag is wing and fuselage Laminarisation of fuselage is very challenging A laminar wing upper side has a bigger effect than lower side (≈ 65%)

For a typical wing application a reduction of total drag in the order of up to 8% is possible by laminar flow on upper side

laminar turbulent



© A

IRB

US

S.A

.S. A

ll rig

hts

rese

rved

. Con

fiden

tial a

nd p

ropr

ieta

ry d

ocum

ent.

What are major influence factors for laminar flow?

Natural laminar flow (NLF): laminar boundary layer by wing airfoil shape only Hybrid laminar flow (HLF): active control (suction, cooling) of boundary layer & airfoil shaping Laminar flow influenced mainly by:

Wing pressure gradient (= airfoil shape) Reynolds number (= size, speed, altitude) Leading edge sweep (= Ma number)

Smoothness of wing surface (waviness, steps, gaps, roughness) Three dimensional disturbances (fasteners, insects, scratches, ...)

Aer

o

Stru

ctur

e



© A

IRB

US

S.A

.S. A

ll rig

hts

rese

rved

. Con

fiden

tial a

nd p

ropr

ieta

ry d

ocum

ent.

Characteristics of laminar Airfoils Cp

x/c

laminar

turbulent

turbulent

laminar

• accelerated flow needed to get large extent of laminar flow • this has a negative effect on shock strength (especially at high Ma) • wing box of laminar wing similar to turbulent but more volume aft • leading edge: sharp, less space front spar more aft

thick & round leading edge

• narrow & sharp leading edge • front spar moved back

• max thickness far aft • increased rear spar height



© A

IRB

US

S.A

.S. A

ll rig

hts

rese

rved

. Con

fiden

tial a

nd p

ropr

ieta

ry d

ocum

ent.

How Hybrid Laminar Flow works

SUCTION SHAPING

Hybrid Laminar Flow Control (HLFC) required at high sweep of leading edge (LE) and high Reynolds number Can be reached by:

• Optimized aerodynamic shape of the airfoil and • Small suction at the leading edge for stabilization of boundary layer • Tight control of the manufactured shapes to remove perturbations at the skin, and

A320 VTP Flight Test with suction 1998



© A

IRB

US

S.A

.S. A

ll rig

hts

rese

rved

. Con

fiden

tial a

nd p

ropr

ieta

ry d

ocum

ent.

Content





5 Summary & Outlook



© A

IRB

US

S.A

.S. A

ll rig

hts

rese

rved

. Con

fiden

tial a

nd p

ropr

ieta

ry d

ocum

ent.

What is different in comparison to the past?

20% 40% 30% 50%

F100 NLF Glove 1992 ATTAS NLF Glove 1987 A340 HLFC Glove A320 HLFC Fin

Past: Aerodynamic basic research with glove technology and hand finishing of surface

Today: Realistic structure concept fulfilling aerodynamic requirements and manufacturing at acceptable cost; demonstration of concepts on ground and in FT

Robust aero design

Specific wind tunnel

test

NLF wing

BLADE Flight Test

Large NLF wing LE ground demonstrator

Joint concepts

Manufacturing trials

Saab

DLR



© A

IRB

US

S.A

.S. A

ll rig

hts

rese

rved

. Con

fiden

tial a

nd p

ropr

ieta

ry d

ocum

ent.

Surface Requirements: Experimental approach

TSP coating Adjustable leading edge step

2D Step testing

2D Waviness in LE + Step

3D Waviness + Multiple Waves

Realistic Structure Simulation

Xtr m

ovem

ent

Surface imperfection increase

Limit?



© A

IRB

US

S.A

.S. A

ll rig

hts

rese

rved

. Con

fiden

tial a

nd p

ropr

ieta

ry d

ocum

ent.

CFD Validation for Surface Requirements

∆Z enlarged

3D Navier-Stokes including WTT wall effects

Experiment in KRG Ma=.75 Cl=design

Re=13Mio

3D CFD Result

temperature distribution



© A

IRB

US

S.A

.S. A

ll rig

hts

rese

rved

. Con

fiden

tial a

nd p

ropr

ieta

ry d

ocum

ent.

Surface quality measurements

flaps measurements before & after assembly

MBF (Composite Structure)

Stringer Position

inboard outboard

Manufacturing Waviness is strongly dependent on build concept (stringer spring in, etc.)

Wing box example Flap box example



© A

IRB

US

S.A

.S. A

ll rig

hts

rese

rved

. Con

fiden

tial a

nd p

ropr

ieta

ry d

ocum

ent.

Content





5 Summary & Outlook



© A

IRB

US

S.A

.S. A

ll rig

hts

rese

rved

. Con

fiden

tial a

nd p

ropr

ieta

ry d

ocum

ent.

NLF Wing Structure Overview • Box

• Minimal change to turbulent box configuration • Lower Skin, Rear Spar and lower flange of Front Spar construction unchanged • Upper Skin certification challenges for “no fastener” joints and integral front spar cap

• Leading Edge • Change to LE design key to meeting NLF requirements • Joint to box critical, challenging build requirements and life management • Slats replaced by Krüger-Flaps

• which provide both high lift and bug protection • Electric WIPS introduced



© A

IRB

US

S.A

.S. A

ll rig

hts

rese

rved

. Con

fiden

tial a

nd p

ropr

ieta

ry d

ocum

ent.

Krüger High-lift and Shielding Concept and Testing

Krueger shielding

Definition of acceptable values for Krueger setting Constraints for structure and kinematics concept

Kinematics Validation Coating Studies 125° Krueger

Numerical &

Experimental Validation



© A

IRB

US

S.A

.S. A

ll rig

hts

rese

rved

. Con

fiden

tial a

nd p

ropr

ieta

ry d

ocum

ent.

NLF Leading Edge Skin sub assembly

Deployed Krüger

Stowed Krüger

Leading edge with high lift installation


electricalWIPS

Thermoplastic sheet

Erosion shield

Sub-structure


© A

IRB

US

S.A

.S. A

ll rig

hts

rese

rved

. Con

fiden

tial a

nd p

ropr

ieta

ry d

ocum

ent.

Examples of Joint and Fastener Head Options

AGI filler cover

DLR floating joint

The joint area and the filler

application is a very critical zone

for a laminar wing structure

concept

Several partners are working

on that topic and

flight demonstration in BLADE

is planned as well



© A

IRB

US

S.A

.S. A

ll rig

hts

rese

rved

. Con

fiden

tial a

nd p

ropr

ieta

ry d

ocum

ent.

Content





5 Summary & Outlook



© A

IRB

US

S.A

.S. A

ll rig

hts

rese

rved

. Con

fiden

tial a

nd p

ropr

ieta

ry d

ocum

ent.

Ground Based Demonstrators in context of TOP-LDA

DLR CFRP LE concept

floating joint

GKN CFRP LE concept

machined joint

Krueger Test rigs BLADE demonstrators

Saab GKN

& machined metal LE

Airbus metal LE concept

metal LE self supported

Ground Based Demonstrator in SFWA

4.5m span NLF leading Edge

Check several approaches and select the best mix out of the different demonstrators



© A

IRB

US

S.A

.S. A

ll rig

hts

rese

rved

. Con

fiden

tial a

nd p

ropr

ieta

ry d

ocum

ent.

Upper Cover DLR NLF Manufacturing Demo

Major Objectives: Development of new CFRP wing cover structure concept and manufacturing demonstration for laminar wing application

wing cover tooling

LaWiPro

Stade 13.6.2013

Surface

quality

analysis



© A

IRB

US

S.A

.S. A

ll rig

hts

rese

rved

. Con

fiden

tial a

nd p

ropr

ieta

ry d

ocum

ent.

GKN Ground based NLF LE Demonstrator

Ground based NLF leading edge demonstrator including Krueger and WIPS integration 4.5m length

Major Objectives:

Demonstration of full LE integration of all NLF leading edge components and manufacturing and assembly quality of large leading edge parts



© A

IRB

US

S.A

.S. A

ll rig

hts

rese

rved

. Con

fiden

tial a

nd p

ropr

ieta

ry d

ocum

ent.

BLADE A340 MSN1 Flight Demonstration

Major Objectives: • Design and manufacturing of NLF

outer wing • Flight testing of NLF wing with

two different structure concepts • Demonstration and validation of

aero design and CFD tools • Validation that selected structure

concepts are feasible and deliver expected surface quality

• Testing of artificial disturbances and operation simulation

• Testing of Kruegershielding

joint

Leading edge with joint to box GKN

Continuous surface Saab

A340-300

Representation of laminar wing on A340 flying test bed



© A

IRB

US

S.A

.S. A

ll rig

hts

rese

rved

. Con

fiden

tial a

nd p

ropr

ieta

ry d

ocum

ent.

Content





5 Summary & Outlook



© A

IRB

US

S.A

.S. A

ll rig

hts

rese

rved

. Con

fiden

tial a

nd p

ropr

ieta

ry d

ocum

ent.

Summary and Outlook

• Surface quality is a major challenge for laminar flow application and detailed knowledge about surface requirements is needed to find best compromise between structure solution and aero performance

• CFD capabilities further improved and validated to predict such effects

• Small, medium size and full wing demonstrators and validation experiments including large scale flight test with A340MSN1 will be used to get confidence in what is possible

• Specific wind tunnel test have been designed to get such precise requirements

• There are several activities with different partners running to find the best structure and manufacturing concept for the leading edge and upper cover of a laminar wing

• Operability of such laminar wings and surface quality degradation effects will be an additional important topic in the future



© A

IRB

US

S.A

.S. A

ll rig

hts

rese

rved

. Con

fiden

tial a

nd p

ropr

ieta

ry d

ocum

ent.

What will come next?

Flight test with simplified HLFC on the VTP

of the A320 DLR ATRA aircraft in 2017

Wing LE HLFC Ground Demonstrator

HLFC system

SAAB

GKN

AERNNOVA

Manufacturing of BLADE large FT demonstrator

Final assembly

Flight test with NLF outboard wings on A340

BLADE demonstrator end of 2017


Kevin Nicholls, EIVW Prepared by Heinz Hansen TOP-LDA ... · filler cover . DLR . floating joint ....

Documents

Transcript of Kevin Nicholls, EIVW Prepared by Heinz Hansen TOP-LDA ... · filler cover . DLR . floating joint ....