Author(s): Keita Yamamoto; Andres Müller; Takuya Ashida; Koichi Yonezawa; François Avellan; Yoshinobu Tsujimoto
Keywords: Dynamic transfer matrix; experimental facilities; hydraulic machines; one-dimensional models; oscillatory flows; velocity measurements
Abstract: This paper introduces an experimental method for the evaluation of dynamic transfer matrices using only pressure transducers. The discharge fluctuations are evaluated from the fluctuation of the pressure difference at different streamwise locations. The transfer matrices of the resistance, the inertance and the compliance elements are determined by using simple flow configurations. This method is then validated by comparing the transfer matrix components to theoretical values. The results show that the direct measurement of the transfer matrices produces good results below the first structural eigenfrequency of the system. Furthermore, a deviation from the mass continuity in the amplitude ratio of the fluctuating upstream and downstream discharges is investigated. This behaviour can be explained with a simple model taking into account the compliance in the system.