Laboratoire national de métrologie et d essais

Size: px

Start display at page:

Download "Laboratoire national de métrologie et d essais"

Elvin Rice
7 years ago
Views:

1 Laboratoire national de métrologie et d essais

2 MEASUREMENT OF AEROSOLS EMITTED FROM VARIOUS STRUCTURAL COMPOSITE MATERIALS DURING POST-CRASH FIRE EVENTS M. Targosz 1, C. Chivas-Joly 1, C. Motzkus 1, F. Gaie-Levrel 1, S. Le Nevé 2, J. Gutierrez 3, J.-M. Lopez-Cuesta 4 1 Laboratoire national de métrologie et d'essais (LNE), 29, av. Roger Hennequin, Trappes, France 2 DGA-Aeronautical Systems, 47 rue Saint-Jean, Balma, France 3 DCNS Research, Indret, La Montagne, France 4 Ecole des Mines d Alès (C2MA), 6 Avenue de Clavières, Alès Cedex, France Corresponding author: marta-malgorzata.targosz@lne.fr 2

3 Content 1. DACOFEU Project Philosophy Samples 2. Experimental part 3. Results Experimental setup Aerosol metrology Number concentration of particles Mass size distribution Microscopic analysis 4. Conclusions 3

4 DACOFEU Project 4

Studies on the environmental effects caused by the dispersion of fibers,

5 Introduction DACOFEU Project Research in aircraft fire safety 5 partners: LNE, DGA, INERIS, DNCS Research and AIRBUS Helicopters Aim & Objectives Studies on the environmental effects caused by the dispersion of fibers, particles and gases released during post-crash aircraft fires from structural composites 5

degradation and combustion of structural composites Numerical modeling of combustion, production and

6 Philosophy of the DACOFEU Project Thermal behaviour of composites Evaluation of the particles dispersion and their potential environmental risk Production of aerosols and gases during thermal degradation and combustion of structural composites Numerical modeling of combustion, production and dispersion of gases and solids during a post-cras fire A post-crash aircraft fire scenario Atmospheric dispersion 6

Focus on aerosols production Structural composites Kind of organic matrix Presence of reinforcement Orientation of reinforcement Kind of nanoobjects Loading of nano-objects Thermal behaviour of

7 Focus on aerosols production Structural composites Kind of organic matrix Presence of reinforcement Orientation of reinforcement Kind of nanoobjects Loading of nano-objects Thermal behaviour of structural composites Production Particles Gases Number concentration Size & mass distribution Evolution Time evolution in time Morphology & chemistry Presence of fibers Qualitative & quantitaitve analysis 7

8 Samples 8

9 Source: R. Younes Structural composites Source: FAA 3D Woven composite material Fibre Reinforced Polymers (FRP): matrix polymer-based resin reinforcement fibres: glass, carbon, aramid, natural fibres and/or additives: flame retardants, nano-objects Aircraft and naval applications due to: exeptional mechanical performance chemical and electrical resistance reduction of weight reduction of fuel consumption thermal resistance 787 Dearamliner composite profile 50% of composites by weight 9

180 kw/m 2 Composite material FAR 25-856-1, Appendix F, Part VII Test Method To Determine the Burnthrough

10 Source: DGA/TA Tested materials Selection criteria of the aircraft and naval composites: the shortest burnthrough time and the highest level of damages the highest yield of the total smoke release Heat flux: 180 kw/m 2 Composite material FAR , Appendix F, Part VII Test Method To Determine the Burnthrough Resistance of Thermal/Acoustic Insulation Materials Kerosene burner Time duration: 15 min MAT 4 MAT 5 MAT 7 MAT

11 Samples Sample Organic matrix Nano-objects Reinforcement Fibers orientation MAT1 no Carbon fibers A no Interlaced MAT2 Epoxy resin A 120 (100 wt.%) no no no MAT3 Epoxy resin A 120 (50 wt.%) Carbon fibers A no Interlaced MAT4 Epoxy resin B 120 (38 wt.%) Carbon fibers B no Interlaced MAT5 Epoxy resin C 180 (29 wt.%) Carbon fibers C no Unidirectional MAT6 Vinyl ester resin (35 wt.%) no Glass fibers no MAT7 Vinyl ester resin (34 wt.%) Carbon nanotubes (1 wt.%) Glass fibers no MAT8 Vinyl ester resin (30 wt.%) Carbon nanotubes (5 wt.%) Glass fibers no 11

12 Experimental part Small scale 12

Experimental setup Aerosol sampling Exhaust duct Fire model Dekati Low Pressure Impactor SEM/AFM (morphology measurement) DMS 500 1st dilution with filtred air (150 C, hot stage) 2nd dilution with

13 Experimental setup Aerosol sampling Exhaust duct Fire model Dekati Low Pressure Impactor SEM/AFM (morphology measurement) DMS 500 1st dilution with filtred air (150 C, hot stage) 2nd dilution with filtred air (20 C, cold stage) Aerodynamic Particle Sizer Aerosol Neutralizer (Source Kr85) SMPS (DMA 3081 LongDMA + CPC3022) Cone Calorimeter Data Acquisition System Heat flux: 75 kw/m 2 with standardized ventilation rate; Pilot spark; Isokinetic sampling Composite sample 4 configurations Long DMA + CPC DLPI DMS APS SEM analysis 13

14 Aerosol metrology, equipement Device Paremeter Range Flowrate Objectives DLPI (Dekati Low Pressure Impactor) Diluteur Dekati L7 (hot dilution) Mass 30 nm 10 µm 10 L/min Flowrate Dilution factor L/min Granulometric mass distribution Classification of aerosol populations and masses Reduce the phenomena of coagulation and saturation measuring equipment metrological Diluteur Dekati VKL10 (cold dilution) Flowrate Dilution factor 10 5L/min (output) need filtered air Congulated and saturated aerosol metrology measuring equipment in reduced temperature CPC (Condensation Particle Counter) DMA L (longdma) + CPC 3775 DMS 500 Concentration (part/cm 3 ) DMA set voltage + CPC evolution of the concentration at a given size Evolution of the particles concentration at a given size Lower particle detection size limit of: 4 nm 10 7 part/cm 3 max 7 nm 10 7 part/cm 3 max L/min 2 nm 1 µm 0.3 ou 1L/min 5 nm 1 µm 8.2 L/min Total concentration of submicron particles inf. 1mm Evolution of the concentration at given size (D elect mobility ) Evolution of the concentration at given size (D elect mobility ) APS 3021 Granulometric size distribution 0.6 µm 20 µm 5L/min Granulometric size distribution (D ae ) Overal measurement range: 2 nm 20 µm 14

15 Results 15

16 Number concentration (x 10 8 particles/cm 3 ) Number concentration of particles, CPC Influence of carbon fiber reinforcement Number concentration (x 10 8 particles/cm 3 ) MAT2, Epoxy resin A 120 alone 3.3x10 8 part.cm -3 AVG AVG + SD AVG - SD MAT3, Epoxy resin A 120/carbon fibers A AVG AVG + SD AVG - SD x10 7 part.cm Time (s) Time (s) Pressence of carbon fiber reinforcement in the epoxy resin results in a significant reduction of particles emission 16

17 Number concentration (x 10 8 particles/cm 3 ) Number concentration of particles, CPC Influence of reinforcement orientation Number concentration (x 10 8 particles/cm 3 ) Number concentration (x 10 8 particles/cm 3 ) MAT3 MAT4 MAT5 Epoxy resin A 120/CF A interlaced Epoxy resin B 120/CF A interlaced Epoxy resin C 180/CF B unidirectional AVG AVG + SD AVG - SD AVG AVG + SD AVG - SD AVG AVG + SD AVG - SD x10 7 part.cm x10 7 part.cm x10 7 part.cm Time (s) Time (s) Time (s) Orientation of CF modifies the thermal properties materials with interlaced CF shows higher thermal stability and reduced global particles emission For materials with interlaced orientation of carbon fibers, only kinetics of particles emission is modified due to different chemical composition of the organic matrices 17

18 Number concentration (x 10 8 particles/cm 3 ) Number concentration of particles, CPC Influence of the CNT mass rate Number concentration (x 10 8 particles/cm 3 ) Number concentration (x 10 8 particles/cm 3 ) MAT6 MAT7 MAT8 Vinyl ester resin/glass fibers Vinyl ester resin/cnt 1%/glass fibers Vinyl ester resin/cnt 5%/glass fibers AVG AVG + SD AVG - SD AVG AVG + SD AVG - SD 6.7x10 7 part.cm x10 7 part.cm x10 7 part.cm AVG AVG + SD AVG - SD Time (s) Time (s) Time (s) Presence of CNTs affects only the kinetics of particle emission The particle production seems to be controlled by the CNTs loading Better dispersion and lower phrr is observed for 1 wt.% mass rate 18

Global number concentration of particles, CPC Influence of the organic matrix Epoxy resin based composites Vinyl ester resin based composites Pure epoxy resin is predominant in particles generation

19 Global number concentration of particles, CPC Influence of the organic matrix Epoxy resin based composites Vinyl ester resin based composites Pure epoxy resin is predominant in particles generation Vinyl ester resin based composites emit 25% more particles than epoxy resin based ones Material with unidiractional carbon fibers produces 1/3 more particles compared to composites with interlaced reinforcement 19

20 Cumulative mass fraction (%) Cumulative particle mass distribution, DLPI Cumulative mass fraction (%) Epoxy resin/carbon fibers composites Vinyl ester resin/cnt composites MAT2 MAT3 MAT4 MAT5 20 MAT6 MAT7 MAT Cut-off diameter (µm) Cut-off diameter (µm) Independent on composite type, around 80% of global particles emission is in submicronic range and only 10%, in the ultrafine range 20

21 Microscopic analysis 21

resin/carbon fibers composites Spectre 2 Lack of fibers in aerosol deposit?

22 Effect on particle morphology and fiber presence? Samples Aerosol deposit Particles Residue Particles & Fibers Linear soot aggregates Epoxy resin/carbon fibers composites Spectre 2 Lack of fibers in aerosol deposit? Need for more detailed microscopic analysis Vinyl ester resin/cnt/ glass fibers composites Spectre 1 CNT Compacted soot aggreagates Spectre 1 Spectre 2 22

23 Conclusions Fire model of 75 kw/m 2 seems to represent a post-crash aircraft fire conditions Aerosol measurements The smoke production is influenced by: chemical composition of organic matrix, presence of carbon fibres or nanotubes and their mass percentage in the material, and orientation of reinforcement Incorporation of carbon fiber reinforcement into epoxy resin matrix reduces significantly particles emission Orientation of CF reinforcement modifies the thermal properties of composite materials and the global particle emission The particle emission seems to be controlled by the CNTs loading Vinyl ester resin composites produce 25% more particles than epoxy resin based ones The average total number concentration of particles obtained during tests is around 6.7x10 7 and 6.3x10 7 particles/cm 3 for epoxy resin and vinyl ester resin based materials, respectively 80% of all produced particles are submicrometric, only 10% ultrafine Morphological analysis shown presence of linear and compacted aggregates, made of very elementary particles in order of nm of aerodynamic diameter, independent on the nature of tested materials 23

24 Thank you for attention! 24

Current and Future Methods for Calibration of Black Carbon Real-Time Mass Instruments

Current and Future Methods for Calibration of Black Carbon Real-Time Mass Instruments Greg Smallwood, Kevin Thomson, Fengshan Liu, Dan Clavel National Research Council Canada, Matthew Dickau, Tyler Johnson,