Stefan Anders

1. Thermal Loading Cases of Hydrogen High Pressure Storage Cylinders Stefan Anders Federal Institute for Materials Research and Testing (BAM) Stefan Anders BAM ICHS – San Sebastian – 2007 September 11-13slide no1

2. Thermal Loading Cases of Hydrogen High Pressure Storage Cylinders Where is the starting point? Stefan Anders BAM ICHS – San Sebastian – 2007 September 11-13slide no2

3. Thermal Loading Cases of Hydrogen High Pressure Storage Cylinders Where is the starting point? Whichproblems have to be solved? Stefan Anders BAM ICHS – San Sebastian – 2007 September 11-13slide no3

4. Thermal Loading Cases of Hydrogen High Pressure Storage Cylinders Where is the starting point? Which problems have to be solved? Whathas been achieved so far? Stefan Anders BAM ICHS – San Sebastian – 2007 September 11-13slide no4

5. Thermal Loading Cases of Hydrogen High Pressure Storage Cylinders Where is the starting point? Which problems have to be solved? What has been achieved so far? Wheredo we still have to go? Stefan Anders BAM ICHS – San Sebastian – 2007 September 11-13slide no5

6. source: DC Where is the starting point? BAM working group ‘Storage Systems’ conducts within StorHy’s subproject ‘Safety Assessment and Regulations’ safety assessment on storage systems for automotive applications. Stefan Anders BAM ICHS – San Sebastian – 2007 September 11-13slide no6

7. Where is the starting point? Hybridstructures (composite and metal or plastic liner) are used for compressed storage. Composite layer is applied on the liner by a winding process. Requirements: - up to 70 MPa operating pressure - temperature range -40°C to +85°C Stefan Anders BAM ICHS – San Sebastian – 2007 September 11-13slide no7

8. Where is the starting point? Test facility at BAM for extreme temperature hydraulic cycling tests max. pressure: 120 MPa (dynamic) temperature: -60°C to +90°C 350 MPa (static) Stefan Anders BAM ICHS – San Sebastian – 2007 September 11-13slide no8

9. Thermal Loading Cases of Hydrogen High Pressure Storage Cylinders Where is the starting point? Whichproblems have to be solved? Stefan Anders BAM ICHS – San Sebastian – 2007 September 11-13slide no9

10. Which problems have to be solved? Problem: Identical cylinders from the same batch show differentsafety relevant structural behavior: - strain level on the same pressure - number of load cycles to failure - burst pressure Stefan Anders BAM ICHS – San Sebastian – 2007 September 11-13slide no10

11. Which problems have to be solved? safe Structural behavior is strongly depend on the boundary condition temperature light weight structure economic production fast production Accurate stress analyses for lifetime prediction Stefan Anders BAM ICHS – San Sebastian – 2007 September 11-13slide no11

12. Thermal Loading Cases of Hydrogen High Pressure Storage Cylinders Where is the starting point? Which problems have to be solved? Whathas been achieved so far? Stefan Anders BAM ICHS – San Sebastian – 2007 September 11-13slide no12

13. What has been achieved so far? Tests on resin systems showed clearly the strong temperature depending material behavior. Stefan Anders BAM ICHS – San Sebastian – 2007 September 11-13slide no13

14. What has been achieved so far? * * Stefan Anders, Residual Stresses in Composite-Metal Structures for High H2 Gas Cylinders, CANCOM 07, Winnipeg, Canada Stefan Anders BAM ICHS – San Sebastian – 2007 September 11-13slide no14

15. temperature distribution probability density function class frequency overall class frequency What has been achieved so far? How often does each temperature class loads the cylinder? Stefan Anders BAM ICHS – San Sebastian – 2007 September 11-13slide no15

16. mean value abs. min mean value standard deviation What has been achieved so far? • Probability density function • (for each calendar months) • Assumption: • - temperature distribution follows a Gaussian (normal) distribution • Input: • mean value of min/max temperature • abs. min/max temperature • = standard deviation Stefan Anders BAM ICHS – San Sebastian – 2007 September 11-13slide no16

17. What has been achieved so far? • Class frequency • (for each calendar months) • setting temperature classes Tk at an increment of T = 5°C • solving the definite integral for each temperature class Stefan Anders BAM ICHS – San Sebastian – 2007 September 11-13slide no17

18. What has been achieved so far? • Overall class frequency • for all temperature classes Tk of the 12 calendar month the arithmetic mean value is determined Stefan Anders BAM ICHS – San Sebastian – 2007 September 11-13slide no18

19. Jokkmokk – max. stress amplitude – frequency 0.27% Jokkmokk – max. frequency 19.6% max. filling temperature What has been achieved so far? Thermal stresses in the liner layer (0°-90°-Al hybrid) Stefan Anders BAM ICHS – San Sebastian – 2007 September 11-13slide no19

20. Thermal Loading Cases of Hydrogen High Pressure Storage Cylinders Where is the starting point? Which problems have to be solved? What has been achieved so far? Wheredo we still have to go? Stefan Anders BAM ICHS – San Sebastian – 2007 September 11-13slide no20

21. Where do we still have to go? So far it could be shown: cold and warm temperatures do load or unload the composite and the liner (fatigue) temperature effect is mainly effective in the resindominated directions lay-up influences the degree of temperature effect (avoid shear stresses) Stefan Anders BAM ICHS – San Sebastian – 2007 September 11-13slide no21

22. Where do we still have to go? Issues which still have to be considered, among others: influence of dynamic loading (pressure and temperature load cycles) which leads to fatigue (degradation models) long term behavior with visco-elastic effects Stefan Anders BAM ICHS – San Sebastian – 2007 September 11-13slide no22

23. Thank you for your attention BAM - III.2 Unter den Eichen 44-46 D-12205 Berlin Germany Stefan Anders Tel.: +49 (0) 30/8104-3981 Fax: +49 (0) 30/8104-1327 E-Mail: stefan.anders@bam.de Stefan Anders BAM ICHS – San Sebastian – 2007 September 11-13slide no23