INTERNATIONAL AIRCRAFT SYSTEMS FIRE PROTECTION …€¦ · Gaetano Mirra (ECS and Ice protection) Antonio Romano (ECS and Ice protection) Salvatore Cuomo (Structural Tests & Prototypes

INTERNATIONAL AIRCRAFT SYSTEMS FIRE

PROTECTION WORKING GROUP MEETING Tolouse, 18th – 19th May, 2016

Multidisciplinary thermo-structural model FAR / CS 25

appendix F Part III

Multi-disciplinary Model for Smoke Movement Simulation

Authors

Gaetano Mirra (ECS and Ice protection)

Antonio Romano (ECS and Ice protection)

Salvatore Cuomo (Structural Tests & Prototypes Manufacturing)

2

Background

Improving fire safety through improved

technologies and materials, in terms of

thermal-structural behaviour, fire penetration

resistance and smoke detection time.

Give more time for A/C evacuation

Protection of on board systems

3

FAR/CS 25.855 (c) civil requirements:

In order to assure, in case of fire on

board, the protection of essential

systems to a “continued safe flight and

landing”, the lining panels (ceiling and

sidewall) installed in a Cargo

Compartment classified as Class C and

E meet the flame penetration test defined

by Appendix F Part III.

Background

4

The FAR/CS 25 Appendix F Part III defines:

• the typology of cargo panels to be tested, and in details they

must be representatives of the installation on a/c, and where

applicable they must include all “features” installed like joints,

lights, smoke detector, air outlet etc.;

• the number of specimens (three) required for each installation;

Acceptance criteria:

• no flame penetration within 5 minutes after application of flame

source;

• the peak of temperature, measured at 10 cm from the

backside surface of the specimen, must not exceed 204°C

when tested in horizontal position.

Currently, the only way to predict the failures of certification tests is the engineering test made with the similar

equipment. This approach is time consuming and expensive.

Flame penetration test

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Flame penetration test

Multi-disciplinary flame penetration model validated

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Testing different material and configuration:

Test campaign - Manufacturing

Monolitic panels and sandwich panels without

junction

Monolitic panels and sandwich panels with

junction

Ref. Cocet research project

7

Test campaign validation tools Thermocouples grids Thermocamera

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Tem

pe

ratu

ra [°

C]

Tempo [sec]

Tc 4

Tc 5

Tc 6

Tc 9

Tc 11

Tc 14

Tc 15

Tc 16

Sp15.Valore

Sp14.Valore

Sp4.Valore

Sp9.Valore

Sp11.Valore

Sp6.Valore

Sp5.Valore

Results necessary for the validation of numerical model

Thermocamera results Temperature measured by the thermocouples

and the thermocamera

Ref. Cocet research project

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Calorimeter Thermocouples

Requirements

Thermocouples temperature: 927 ± 38°C

Calorimeter heat flux: 9.1± 0∙6 Watts/cm2

Velocity at end of draft tube: 7.9-9.1 m/s

Calorimetro

Thermocouples

Calibration phase

Ref. Cocet research project

M. Panelli, L. Cutrone, G. Mirra “CFD Simulation Of Flame

Penetration Test – Calibration Phase” XXIII AIDAA Congress,

Torino (TO), Italy, 17-19 November 2015.

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Multidisciplinary thermo-structural model Geometrical model Flame CFD model FEM model Thermo-mechanical

material properties

MSC Software Corporation ConfidentialMSC Confidential

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Glass reinforced plastic - Mechanical Properties

E Glass Fiber

0.00E+00

5.00E+09

1.00E+10

1.50E+10

2.00E+10

2.50E+10

0 200 400 600 800 1000 1200

T [°K]

E [

N/m

2]

= 1.2 e-6 (temperature independent)

= 1600 kg/m3

= 0.3

Multidisciplinary thermo-structural model

After 60s After 120s After 240s After 300s

Multidisciplinary integration model

CFD model Thermostructural model

Ref. Cocet research project

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Validation phase

Comparison between temperature pattern on the bottom side of the panel (thermocouples

results vs simulation) to verify and tune flame simulation model.

Comparison between temperature pattern on the top side of the panel (thermocamera results

vs simulation) to verify the thermo-mechanical behaviour of the specimen and tune the

simulation model.

Ref. Cocet research project

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Conclusion 1

Benefit:

•Reduce the time and costs of specimen suppling.

• Reduce test time, the experimental activity is minimized to the confermation of

the results for the design approval.

•Reduce number of development tests and certification tests (cost reduction)

•Reduce risk associated to the development phase: the refinement is anticipated

in the concept phase. (cost reduction)

•A wide spectrum of configurations and cases (optimized design)

Applicability:

•Simulate the thermal-mechanical behaviour of a specimen in fire condition.

•Simulate the flame penetration test .

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In accordance with FAR/CS 25.858 (a) civil

requirement, when the certification with cargo

compartment fire detection provisions is

requested, in case of fire and smoke on the

board, the smoke detection system must

provide a visual indication to the flight crew

within one minute after the start of a fire.

Currently, engineering tests made with the similar equipment are the only means for

system development and certification; this approach is time consuming and

expensive.

Smoke detection system test

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Smoke detection system test

Multi-disciplinary Smoke movement model validated

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Air distribution system Door

Left side final distribution

Right side final distribution

Smoke detection system control box

Left side extraction line Right side extraction line

Test rig

Ref. Cocet research project

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Tools:

Pressure sensors,

Temperature sensors

PIV

Camera

Smoke generator

Control box

Smoke detectors

Test rig

Test results. Air massflow and temperature in each branch of air distribution system

Smoke detectors activation time

Velocity pattern in characteristic slice defined in the test room

Smoke tracking

Slot 1 DXSlot 2 DX

Slot 1 SXSlot 2 SX

Ref. Cocet research project

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Assumption and boundary conditions

Air Massflow and temperature measured during the test campaign

Smoke generator off

Modello CFD

Results:

Air massflow and

temperature pattern

Velocity pattern

Pressure pattern

Multidisciplinary model - Air

Ref. Cocet research project

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Validation of fluid dynamic model with smoke generator off Measure of velocity pattern and velocity

vector field through PIV tool.

Test results CFD

Multidisciplinary model validation - PIV

Ref. Cocet research project

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Assumption and boundary conditions

Air Massflow and temperature measured during the test campaign

Model bi-component: air and smoke. The smoke characteristics are defined on the basis of dedicated model defined in Italian

research project (ref. Cocet research project)

Temperature of smoke

Smoke distribution after 60 s

Modello CFD

Smoke generator

Chemical

characteristics and

mass fraction of the

smoke

Defintion of

new fluid

element in

the CFD

tool:

Smoke

Multidisciplinary model - Smoke

Ref. Cocet research project

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Real test Multidisciplinary model results

Multidisciplinary model validation – smoke movement

Ref. Cocet research project

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10 sec

50 sec

30sec

Multidisciplinary model validation – smoke movement

Ref. Cocet research project

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Conclusion 2

Benefit:

•Passenger comfort evaluation.

•Optimization of Smoke detector position and number.

•Evaluation of emergency labels position.

•Reduce number of development tests and certification tests. (cost reduction)

•Reduce risk associated to the development phase: the refinement is anticipated

in the concept phase. (cost reduction)

•A wide spectrum of configurations and cases (optimized design)

Applicability:

•Simulate the thermal and fluid-dynamic environment in a conditioned cabin.

•Simulate and predict the flow of the smoke generated by a smoke generator

located inside a conditioned cabin.

•Verify and predict the smoke detectors time activation and sequence

activation.

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NEXT STEPS AND IMPROVEMENT

Smoke movement model:

• Dedicated test to measure the smoke mass flow

• Dedicated test to measure the smoke detector activation time

• Dedicated test to measure in detail the chemical characteristics of the smoke

Flame penetration test model

• Improve model reliability through:

• validation activities with experimental results

• materials chemical and thermo mechanical characteristics data gathering

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Antonio Romano

Chief Technical Office - General Systems

Head of ECS & Ice Protection

Finmeccanica S.p.A.

Viale Dell’Aeronautica, snc – Pomigliano D’Arco (NA) - 80038 - Italy

Tel: +390818873783 Fax: +390818872451 Cell: 393440531610

[email protected]

www.finmeccanica.com

Gaetano Mirra

Chief Technical Office

General Systems - ECS and Ice protection

Finmeccanica S.p.A

Viale dell'Aeronautica, snc - 80038 Pomigliano d'Arco (NA) Italy

Phone: +39 081 887 6209, Fax: +39 081 887 2200

e-mail: [email protected]

www.finmeccanica.com

Salvatore Cuomo

Chief Technical Office

Structural Tests & Prototypes Manufacturing

Finmeccanica S.p.A

Viale dell'Aeronautica snc

80038 - Pomigliano D'Arco (Na)

Tel. : 081 8872997

e-mail: [email protected]

www.finmeccanica.com

THANK YOU FOR YOUR ATTENTION