A proposal for the dynamic strain interpolation on hydroelectric turbine runner
Résumé
Abstract The large operation range of hydroelectric turbine, caused by the increasing changes in the electrical network usage, leads to higher dynamic stress fluctuation on runner. However, the experimental data cannot cover all the possible operating conditions. The missing data in some turbine operation zones generates a challenge for the recovery of the highest dynamic strain. This paper proposes a methodology for the interpolation of such strains between operating conditions by using the kriging method. The case study focuses on the interpolation of the part load rope which is an important component in the dynamic strain of a Francis turbine runner. Two interpolation approaches, inspired by spatio-temporal kriging and cokriging, are applied and compared. Finally, some suggestions are proposed to improve the recovery of operating conditions using interpolation process.