Prof. Dr. K. Be rne r 1
iS - engineer ing GmbHInstitute for SANDWICHTECHNOLOGY
Air and water permeability ofsandwich panel joints
– requirements and state of research –
Klaus BernerMarc Rippel
EPAQ Congress Porto 16. – 17.09.2010
www.sandwichtechnik.com
Prof. Dr. K. Be rne r 2
iS - engineer ing GmbHInstitute for SANDWICHTECHNOLOGY
Prof. Dr. K. Be rne r 3
iS - engineer ing GmbHInstitute for SANDWICHTECHNOLOGY
individual designed jointsfor thespecial situation
sandwich-panel joints(longitudinal), layout relating to theproduct,only these jointsare topic in theCE-mark
Prof. Dr. K. Be rne r 4
iS - engineer ing GmbHInstitute for SANDWICHTECHNOLOGY
Type of panel-joints
Prof. Dr. K. Be rne r 5
iS - engineer ing GmbHInstitute for SANDWICHTECHNOLOGY
One of the following three test classes shall be used:
- Class A: Demanding applications with heavy rain and wind. The assembly shall be watertight up to 1 200 Pa;
- Class B: Normal applications. The assembly shall be watertight up to 600 Pa;- Class C: Low requirement applications. The assembly shall be watertight up to 300 Pa.
EN 14509: A.11 Water permeability – resistance to driving rain under pulsatingpressure
Where required, the resistance of a sandwich panel assembly to driving rain under pulsatingair pressure shall be tested according to
EN 12865
Prof. Dr. K. Be rne r 6
iS - engineer ing GmbHInstitute for SANDWICHTECHNOLOGY
EN 14509: A.12 Air permeability
Calculations and results:
acccording to EN 12114
Where required, the air t ightness of a sandwich panel assembly shall be tested according to
EN 12114
Prof. Dr. K. Be rne r 7
iS - engineer ing GmbHInstitute for SANDWICHTECHNOLOGY
Why is the tightness of the joints so important?
The resistance to driving rain and the air t ightness are official required, e.g. in national standards. In Germany for air t ightness:• Change of air 1,5 or 3 per h• Air permeability (air loss) < 0,1 m3/ (m*h*daPa2/ 3)
Very often more stringent requirements are demanded of the clients• e.g. for cold stores, because of the nitrogen atmosphere• costs of a loss of 100 litre nitrogen ca. 400 €
Example:Store, ca. 30 000 m3, 5 000 m2 wall, 5 000 m jointsWith 0,01 m3/ (m*h) (=1/ 10 minimal value)
=> 50 m3/ h=> 70 l nitrogen/ h=> 280 €/ h
minimal values
Prof. Dr. K. Be rne r 8
iS - engineer ing GmbHInstitute for SANDWICHTECHNOLOGY
The physical situation regarding the tightness of joint is complicated:
Inside the joint moving particles are relevant as a dynamic fluid.
The tightness depends on
convection
• convection (lat. convehere = to take along, pick up) is the transport of material or physical characteristics due of the movement of particles
diffusion
• in a closed system the diffusion produces the decomposition of different concentrations to the point of complete mixing
Cold
thermal andhumidityeffects
Prof. Dr. K. Be rne r 9
iS - engineer ing GmbHInstitute for SANDWICHTECHNOLOGY
Metallic faceheat conduction
Core material
Air passageVapour diffusion
Intrusion ofdriving rain
Sealing tape
distanceoutside withtolerances
gap inside
?
Prof. Dr. K. Be rne r 10
iS - engineer ing GmbHInstitute for SANDWICHTECHNOLOGY
Research Project „DiFuSe“
Project executing organisation
Project executing research institut: Institute for Sandwichtechnology (iS-Mainz), FH Mainz
Project leader: Prof. Dr. Klaus BernerResponsible research assistant: Dipl.-Ing. Marc Rippel
Research partner: 15 industrial partners, e.g. ECP, FischerProfil, Hammersen, Romakowski, ThyssenKrupp, Trimo, etc.
Co-operation partner: University Darmstadt (TU), Prof. Lange
„Research and Development of tight jointsfor sandwich panelsused in building structures“
Prof. Dr. K. Be rne r 11
iS - engineer ing GmbHInstitute for SANDWICHTECHNOLOGY
Main focus of the research project „DiFuSe“, regarding the effect of panel-joints concerning the tightness:
1. Analysis by calculation using a computer program for computational fluid dynamic (CFD) Possibilit ies for e.g. efficient optimization of joint geometries or sealing strips withoutexpensive tests
2. Analysis by tests using a test arrangement according to EN 12865 and 12114Possibilit ies to get official results for different types of joints, influence of different gapsor sealing strips
Prof. Dr. K. Be rne r 12
iS - engineer ing GmbHInstitute for SANDWICHTECHNOLOGY
Test arrangement for checking- resistance to driving rain according to EN 12865- air t ightness according to EN 12114
Prof. Dr. K. Be rne r 13
iS - engineer ing GmbHInstitute for SANDWICHTECHNOLOGY
CEN TC 128 SC11, Working Group 1Water and Air permeability, Annex A.11 and A.12
Statement:
• Horizontal standard is not clear enough regarding theconfiguration of the joints
• Testing should be clarified to improve the comparisonbetween the test results of manufacturers
Prof. Dr. K. Be rne r 14
iS - engineer ing GmbHInstitute for SANDWICHTECHNOLOGY
Proposal of Working Group 1 for the assessment of the jointsin the tests
A11.3 and A12.3 Test specimens:
The length of the panel shall be 3 m or greater. At least 3 panels shall beused to create a minium of two vertical or horizontal joints.
The fixing of the panels shall be at 3 m (at the end of the panels) so thatthe panels bend independently from the frame.
Prof. Dr. K. Be rne r 15
iS - engineer ing GmbHInstitute for SANDWICHTECHNOLOGY
Test arrangement for checking- resistance to driving rain according to EN 12865- air t ightness according to EN 12114
Prof. Dr. K. Be rne r 16
iS - engineer ing GmbHInstitute for SANDWICHTECHNOLOGY
Class A 1)
a = 0,014 m3/(mhdaPa0,73) 2)
1) (Demanding applicationswith heavy rain and wind)2) air permeability coefficient according to EN 12114
Prof. Dr. K. Be rne r 17
iS - engineer ing GmbHInstitute for SANDWICHTECHNOLOGY
Marc Rippel 18
Institute for SANDWICHTECHNOLOGY
Table ofContents
1. Test apparatus• Regulation technology
2. Standard conforming test procedure• Air permeability• Water permeability
3. Test results• Evaluation• Presentation
4. Computational Fluid Dynamics (CFD)• Advantage of CFD• Development of the CFD model• Results
5. Conclusion
Marc Rippel 19
Institute for SANDWICHTECHNOLOGY
1. Test apparatus
•
2. Test procedure
•
3. Test Results
•
4. CFD
•
5. Conclusion
Marc Rippel 20
Institute for SANDWICHTECHNOLOGY
Air permeability1. Test
apparatus
•
2. Test procedure
•
3. Test Results
•
4. CFD
•
5. Conclusion
Marc Rippel 21
Institute for SANDWICHTECHNOLOGY
Regulation technology
Max. pressure in test chamber• +/ - 5000Pa (accuracy 1 Pa)
Realisable air flow volume:• 0 to 1.3 m3/ h (measuring range 0.0006 m3/ h)• 1.3 to 650 m3/ h (measuring range 0.1 m3/ h)
Water flow volume• 2 to 50 l/ min (measuring range 0.1 l/ min)• Separable in run-off water and driving rain
Rotatability from 0 to 90°Fog machine
1. Test apparatus
•
2. Test procedure
•
3. Test Results
•
4. CFD
•
5. Conclusion
Marc Rippel 22
Institute for SANDWICHTECHNOLOGY
1. Test apparatus
•
2. Test procedure
•
3. Test Results
•
4. CFD
•
5. Conclusion
Pressure-line Air flow volume
Pre
ssur
e[P
a]
Test procedure air permeability
Air flow
volume
[m3/h]
Time [min]
Marc Rippel 23
Institute for SANDWICHTECHNOLOGY
Air permeability
1. Test apparatus
•
2. Test procedure
•
3. Test Results
•
4. CFD
•
5. Conclusion
Marc Rippel 24
Institute for SANDWICHTECHNOLOGY
Air permeability
1. Test apparatus
•
2. Test procedure
•
3. Test Results
•
4. CFD
•
5. Conclusion
Marc Rippel 25
Institute for SANDWICHTECHNOLOGY
1. Test apparatus
•
2. Test procedure
•
3. Test Results
•
4. CFD
•
5. Conclusion
C
Marc Rippel 26
Institute for SANDWICHTECHNOLOGY
1. Test apparatus
•
2. Test procedure
•
3. Test Results
•
4. CFD
•
5. Conclusion
Geometries of
tested joints
Marc Rippel 27
Institute for SANDWICHTECHNOLOGY
1. Test apparatus
•
2. Test procedure
•
3. Test Results
•
4. CFD
•
5. Conclusion
Marc Rippel 28
Institute for SANDWICHTECHNOLOGY
1. Test apparatus
•
2. Test procedure
•
3. Test Results
•
4. CFD
•
5. Conclusion
Marc Rippel 29
Institute for SANDWICHTECHNOLOGY
1. Test apparatus
•
2. Test procedure
•
3. Test Results
•
4. CFD
•
5. Conclusion
Marc Rippel 30
Institute for SANDWICHTECHNOLOGY
1. Test apparatus
•
2. Test procedure
•
3. Test Results
•
4. CFD
•
5. Conclusion
Marc Rippel 31
Institute for SANDWICHTECHNOLOGY
Air permeability1. Test
apparatus
•
2. Test procedure
•
3. Test Results
•
4. CFD
•
5. Conclusion
Marc Rippel 32
Institute for SANDWICHTECHNOLOGY
Waterpermeability
1. Test apparatus
•
2. Test procedure
•
3. Test Results
•
4. CFD
•
5. Conclusion
Pres
sure
[Pa]
Time [s]
Marc Rippel 33
Institute for SANDWICHTECHNOLOGY
1. Test apparatus
•
2. Test procedure
•
3. Test Results
•
4. CFD
•
5. Conclusion
Test procedure water permeability
Pressure-line
Time [min]
Pre
ssur
e[P
a]
Marc Rippel 34
Institute for SANDWICHTECHNOLOGY
Results of waterpermeability
Classification
- Class A: Joint shall be watertight up to 1 200 Pa;
- Class B: Joint shall be watertight up to 600 Pa;
- Class C: Joint shall be watertight up to 300 Pa.
1. Test apparatus
•
2. Test procedure
•
3. Test Results
•
4. CFD
•
5. Conclusion
Marc Rippel 35
Institute for SANDWICHTECHNOLOGY
CFD…
…is an established method of fluid mechanics
…is able to simulate realistic movement of fluids including the existanceof unsteady flow or non-laminar flow
…uses numerical methods and algorithms to solve and analyze problems that involve fluid flows
…solves complex systems of non-linear equations which describe the motion of fluid substances (Navier-Stokes) by computation
…enables to visualize movement of any kind of fluid or gas in or around material systems (simulation)
…performs millions of calculations to simulate the interaction of liquids and gases with surfaces defined by boundary conditions
1. Test apparatus
•
2. Test procedure
•
3. Test Results
•
4. CFD
•
5. Conclusion
Marc Rippel 36
Institute for SANDWICHTECHNOLOGY
1. Test apparatus
•
2. Test procedure
•
3. Test Results
•
4. CFD
•
5. Conclusion
1.Physical propertiesEquationsof fluid mechanicsunderassumption of a newtonian fluid (Navier-Stokes), material properties, turbulencemodelGeometryImport, Defining regions(solid/ fluid)
2.Discretization of geometry→“meshing“ Surface Mesh/ Volume Mesh
Discretization of physics→Transformation of differential equations intoalgebraic functions ( by FVM) Construction of an solvable algebraic systemof equations (similar number of equationsand unknowns)
3.Post processing (exposition of results)
Structure of a CFD simulation system
1.
3.
2.
Marc Rippel 37
Institute for SANDWICHTECHNOLOGY
1. Test apparatus
•
2. Test procedure
•
3. Test Results
•
4. CFD
•
5. Conclusion
Longitudinal joint Free stream
Sandwich panels
Test chamber
Marc Rippel 38
Institute for SANDWICHTECHNOLOGY
1. Test apparatus
•
2. Test procedure
•
3. Test Results
•
4. CFD
•
5. Conclusion
Longitudinal joint Free streamTest chamber
Marc Rippel 39
Institute for SANDWICHTECHNOLOGY
1. Test apparatus
•
2. Test procedure
•
3. Test Results
•
4. CFD
•
5. Conclusion
Marc Rippel 40
Institute for SANDWICHTECHNOLOGY
1. Test apparatus
•
2. Test procedure
•
3. Test Results
•
4. CFD
•
5. Conclusion
Marc Rippel 41
Institute for SANDWICHTECHNOLOGY
1. Test apparatus
•
2. Test procedure
•
3. Test Results
•
4. CFD
•
5. Conclusion
Marc Rippel 42
Institute for SANDWICHTECHNOLOGY
1. Test apparatus
•
2. Test procedure
•
3. Test Results
•
4. CFD
•
5. Conclusion
State of the art concerning joint permeability• Possibility of testing according to EN 14509 to get official results(A-value,
classof water-tightness)• Possibility of computer-based calculation (CFD) to get results, in particular
for efficient optimization of jointswithout expensive tests
Class A
a = 0,014 m3/(mhdaPa0,73)
Benefit manufacturer:• marketing potential• product relatedcharachteristicsof jointpermeability
Benefit clients:• transparency regarding tojoint permeability• comparability
Prof. Dr. K. Be rne r 43
iS - engineer ing GmbHInstitute for SANDWICHTECHNOLOGY
Thank you for your attention!
Klaus BernerMarc Rippel
www.sandwichtechnik.com