EUROPEAN SMALL HYDROPOWER ASSOCIATION HIDROENERGIA 2008, JUNE 11-13, BLED SLOVENIA
EUROPEAN SMALL HYDROPOWER ASSOCIATION HIDROENERGIA 2008, JUNE 11-13, BLED SLOVENIA
DAMAGES IN POWER PLANTS – EXPERIENCES AND AVOIDANCE Prof. Dr.-Ing. Henning Altmann / Dipl.-Ing. (FH) Peter Würl
Von der IHK zu Coburg öffentlich bestellte und vereidigte Sachverständige Prof. Dr.-Ing. H. Altmann und Dipl.-Ing. (FH) H.-P. Würl, D-96479 Weitramsdorf b. Coburg
13. Juni 2008 1
EUROPEAN SMALL HYDROPOWER ASSOCIATION HIDROENERGIA 2008, JUNE 11-13, BLED SLOVENIA
OUTLINE
I ANALYSIS OF A DAMAGE THAT OCCURED, BECAUSE THE TECHNICAL BASIS HAD NOT BEEN CLARIFIED CAREFULLY ENOUGH
II ANALYSIS OF A DAMAGE THAT OCCURED, BECAUSE THE DESIGN, FEASIBILITY AND PROFITABILITY WERE INSUFFICIENT
III CONCLUSIONS AND RECOMMENDATIONS
Von der IHK zu Coburg öffentlich bestellte und vereidigte Sachverständige Prof. Dr.-Ing. H. Altmann und Dipl.-Ing. (FH) H.-P. Würl, D-96479 Weitramsdorf b. Coburg
13. Juni 2008 2
EUROPEAN SMALL HYDROPOWER ASSOCIATION HIDROENERGIA 2008, JUNE 11-13, BLED SLOVENIA
I ANALYSIS OF A DAMAGE THAT OCCURED, BECAUSE THE TECHNICAL BASIS HAD NOT BEEN CLARIFIED CAREFULLY ENOUGH I.1 Power-plant that is driven by an unconventional cylindrical shaped water-wheel, installed in a spillway
Von der IHK zu Coburg öffentlich bestellte und vereidigte Sachverständige Prof. Dr.-Ing. H. Altmann und Dipl.-Ing. (FH) H.-P. Würl, D-96479 Weitramsdorf b. Coburg
13. Juni 2008 3
EUROPEAN SMALL HYDROPOWER ASSOCIATION HIDROENERGIA 2008, JUNE 11-13, BLED SLOVENIA
I.1 Power-plant that is driven by an unconventional cylindrical shaped water-wheel, installed in a spillway
Fig. 1: Old conception (above) and the new water-wheel installed in the spillway (below) Von der IHK zu Coburg öffentlich bestellte und vereidigte Sachverständige Prof. Dr.-Ing. H. Altmann und Dipl.-Ing. (FH) H.-P. Würl, D-96479 Weitramsdorf b. Coburg
13. Juni 2008 4
EUROPEAN SMALL HYDROPOWER ASSOCIATION HIDROENERGIA 2008, JUNE 11-13, BLED SLOVENIA
I.1 Power-plant that is driven by an unconventional cylindrical shaped water-wheel, installed in a spillway
Fig. 2: Sketch of the plant and the broken water-wheel
Von der IHK zu Coburg öffentlich bestellte und vereidigte Sachverständige Prof. Dr.-Ing. H. Altmann und Dipl.-Ing. (FH) H.-P. Würl, D-96479 Weitramsdorf b. Coburg
13. Juni 2008 5
EUROPEAN SMALL HYDROPOWER ASSOCIATION HIDROENERGIA 2008, JUNE 11-13, BLED SLOVENIA
I.1 Power-plant that is driven by an unconventional cylindrical shaped water-wheel, installed in a spillway
Fig. 3: Examination of tensile strength
Von der IHK zu Coburg öffentlich bestellte und vereidigte Sachverständige Prof. Dr.-Ing. H. Altmann und Dipl.-Ing. (FH) H.-P. Würl, D-96479 Weitramsdorf b. Coburg
13. Juni 2008 6
EUROPEAN SMALL HYDROPOWER ASSOCIATION HIDROENERGIA 2008, JUNE 11-13, BLED SLOVENIA
I.1 Power-plant that is driven by an unconventional cylindrical shaped water-wheel, installed in a spillway
Fig. 4: Changes in the structure of material caused by the welding procedure (Metallurgical longitudinal cross-section) Von der IHK zu Coburg öffentlich bestellte und vereidigte Sachverständige Prof. Dr.-Ing. H. Altmann und Dipl.-Ing. (FH) H.-P. Würl, D-96479 Weitramsdorf b. Coburg
13. Juni 2008 7
EUROPEAN SMALL HYDROPOWER ASSOCIATION HIDROENERGIA 2008, JUNE 11-13, BLED SLOVENIA
I.1 Power-plant that is driven by an unconventional cylindrical shaped water-wheel, installed in a spillway
Important implications with respect to this damage: • This wide water-wheel was outfitted with an unsuitable lateral suspension. • Caused by the asymmetric generator drive unbalanced stress and torque exist. • No calculation under dynamic water flow had been carried out. • The manufacturer of this water-wheel had no experience in the field of hydropower-plants.
Summary A wrong calculation resulted in a water-wheel with insufficient mechanical stability!
Von der IHK zu Coburg öffentlich bestellte und vereidigte Sachverständige Prof. Dr.-Ing. H. Altmann und Dipl.-Ing. (FH) H.-P. Würl, D-96479 Weitramsdorf b. Coburg
13. Juni 2008 8
EUROPEAN SMALL HYDROPOWER ASSOCIATION HIDROENERGIA 2008, JUNE 11-13, BLED SLOVENIA
II. ANALYSIS OF A DAMAGE THAT OCCURED, BECAUSE THE DESIGN, FEASIBILITY AND PROFITABILITY WERE INSUFFICIENT II.1 The development of a scour as a result of a non suitable design after spillway- restoration.
Von der IHK zu Coburg öffentlich bestellte und vereidigte Sachverständige Prof. Dr.-Ing. H. Altmann und Dipl.-Ing. (FH) H.-P. Würl, D-96479 Weitramsdorf b. Coburg
13. Juni 2008 9
EUROPEAN SMALL HYDROPOWER ASSOCIATION HIDROENERGIA 2008, JUNE 11-13, BLED SLOVENIA
II.1 The development of a scour as a result of a non suitable design after spillway- restoration.
Fig. 5: Cross-section through concrete crest
Von der IHK zu Coburg öffentlich bestellte und vereidigte Sachverständige Prof. Dr.-Ing. H. Altmann und Dipl.-Ing. (FH) H.-P. Würl, D-96479 Weitramsdorf b. Coburg
13. Juni 2008 10
EUROPEAN SMALL HYDROPOWER ASSOCIATION HIDROENERGIA 2008, JUNE 11-13, BLED SLOVENIA
II.1 The development of a scour as a result of a non suitable design after spillway- restoration.
Fig. 6: Results after surveying of scour
Von der IHK zu Coburg öffentlich bestellte und vereidigte Sachverständige Prof. Dr.-Ing. H. Altmann und Dipl.-Ing. (FH) H.-P. Würl, D-96479 Weitramsdorf b. Coburg
13. Juni 2008 11
EUROPEAN SMALL HYDROPOWER ASSOCIATION HIDROENERGIA 2008, JUNE 11-13, BLED SLOVENIA
II.1 The development of a scour as a result of a non suitable design after spillway- restoration.
Fig. 7: View on the modified weir and on the scour, seen from the right bank Von der IHK zu Coburg öffentlich bestellte und vereidigte Sachverständige Prof. Dr.-Ing. H. Altmann und Dipl.-Ing. (FH) H.-P. Würl, D-96479 Weitramsdorf b. Coburg
13. Juni 2008 12
EUROPEAN SMALL HYDROPOWER ASSOCIATION HIDROENERGIA 2008, JUNE 11-13, BLED SLOVENIA
II.1 The development of a scour as a result of a non suitable design after spillway- restoration.
Important implications with respect to this damage: • Caused by the modified concrete construction the crest of the weir itself had been shifted for several meters downstream. • The slope to downstream did change, a vertical edge was formed, the surface altered from smooth to rough. • The effective width of the weir had been reduced by incorporating a fish pass and a undersluice, whilst a higher load by the same water quantity did arise.
• No detailed calculation of hydraulics for the new weir-geometry had been made. It was not realized, that now a steady immersion jet could not be maintained. • The employer tried to save money. The payment to his consultant was cut and the control of the works was done by own staff. • Rip-rap set in concrete at the surface of the weir had not been done accurately and had not been checked.
Summary Restorations, repairs and modernizations of a complex magnitude, these works should be designed and controlled by competent experts!
Von der IHK zu Coburg öffentlich bestellte und vereidigte Sachverständige Prof. Dr.-Ing. H. Altmann und Dipl.-Ing. (FH) H.-P. Würl, D-96479 Weitramsdorf b. Coburg
13. Juni 2008 13
EUROPEAN SMALL HYDROPOWER ASSOCIATION HIDROENERGIA 2008, JUNE 11-13, BLED SLOVENIA
III CONCLUSIONS AND RECOMMENDATIONS
Von der IHK zu Coburg öffentlich bestellte und vereidigte Sachverständige Prof. Dr.-Ing. H. Altmann und Dipl.-Ing. (FH) H.-P. Würl, D-96479 Weitramsdorf b. Coburg
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EUROPEAN SMALL HYDROPOWER ASSOCIATION HIDROENERGIA 2008, JUNE 11-13, BLED SLOVENIA
III.
CONCLUSIONS AND RECOMMENDATIONS
Fig. 8: Steps to design a hydropower-plant Von der IHK zu Coburg öffentlich bestellte und vereidigte Sachverständige Prof. Dr.-Ing. H. Altmann und Dipl.-Ing. (FH) H.-P. Würl, D-96479 Weitramsdorf b. Coburg
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EUROPEAN SMALL HYDROPOWER ASSOCIATION HIDROENERGIA 2008, JUNE 11-13, BLED SLOVENIA
III.
CONCLUSIONS AND RECOMMENDATIONS
Fig. 9: Diagram for refurbishment of hydropower-plants Von der IHK zu Coburg öffentlich bestellte und vereidigte Sachverständige Prof. Dr.-Ing. H. Altmann und Dipl.-Ing. (FH) H.-P. Würl, D-96479 Weitramsdorf b. Coburg
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EUROPEAN SMALL HYDROPOWER ASSOCIATION HIDROENERGIA 2008, JUNE 11-13, BLED SLOVENIA
Thank you ...... Danke! Questions ?.... please talk with us !
Study the past if you would define the future. Confucius
Von der IHK zu Coburg öffentlich bestellte und vereidigte Sachverständige Prof. Dr.-Ing. H. Altmann und Dipl.-Ing. (FH) H.-P. Würl, D-96479 Weitramsdorf b. Coburg
13. Juni 2008 17