Modeling the dynamic behavior of turbine runner blades during transients using indirect measurements

28th IAHR symposium on Hydraulic Machinery and Systems

Diagne, I.^1 ; Gagnon, M.^2 ; Tahan, A.^1

École de Technologie Supérieure (ÉTS), Montréal

QC

H3C 1K3, Canada^1

Institut de Recherche d'Hydro-Québec (IREQ), Varennes

QC

J3X 1S1, Canada^2

关键词: Direct measurement;    Dynamic behaviors;    High amplitudes;    Highly-correlated;    Indirect measurements;    Measurement campaign;    Transient events;    Turbine runner;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/49/7/072014/pdf
DOI  :  10.1088/1755-1315/49/7/072014

来源: IOP

【 摘 要 】

Turbine start-up transients are induced by the wicket gates opening sequence and generate high amplitude stress cycles. These stress cycles have a detrimental effect leading to faster crack growth in the runner blades. Using a series of direct measurements taken on a prototype runner in order to find the optimal start-up parameters exposes both the runner and the instrumentation to a series of successive damaging transient events during the optimization process. To solve this, finding sensors strongly correlated to strain gauges and whose signals can be easily obtained to identify a model to predict the strain, instead of directly measuring it, would reduce the risk, cost and downtime associated with a measurement campaign. This paper shows that turbine shaft torsion measurements is highly correlated to the strain at a runner blade hotspot, and we demonstrate that the ARMAX model can be used to represent the dynamic system in order to minimize the strain on blades.