Title:
|
Influence of non-rigid surfaces on the dynamic response of a submerged and confined disk
|
Author:
|
Valentín Ruiz, David; Presas Batlló, Alexandre; Egusquiza Estévez, Eduard; Valero Ferrando, Ma. del Carmen
|
Other authors:
|
Universitat Politècnica de Catalunya. Departament de Mecànica de Fluids; Universitat Politècnica de Catalunya. FLUIDS - Enginyeria de Fluids |
Abstract:
|
Determining the dynamic response of submerged and confined disk-like structures is of interest in
the hydraulic turbines field. Disks present similar dynamic characteristics than hydraulic turbine
runners, especially in the mode-shapes associated with each natural frequency. The dynamic response
of submerged structures is heavily affected by the added mass and damping as well as the proximity of
solid boundaries. In all studies the solid boundaries are commonly considered completely rigid,
however in real cases this is not always true. This fact occurs in some hydraulic turbines where the
casing is not completely stiff and it may have some dynamic response in the frequency range of the
runner, which may affect its dynamic behavior.
To determine the influence of the casing stiffness on a vibrating disk submerged in water an
experimental investigation has been carried out. A test rig consisting of a disk attached to a shaft
inside a cylindrical tank closed with two different covers with different stiffness has been built up. The
disk was impacted using a hammer and both disk and covers responses were measured with different
accelerometers. Pressure sensors mounted on the covers have also been used. Natural frequencies of
the disk have been obtained, compared and discussed for different disk to cover distances. |
Abstract:
|
Peer Reviewed |
Subject(s):
|
-Àrees temàtiques de la UPC::Enginyeria mecànica::Mecànica de fluids -Fluid mechanics -Hydraulic turbines -- Dynamics -Added mass -Natural frequency -Non-rigid surface -Dynamic response -Mecànica de fluids -Turbines hidràuliques |
Rights:
|
|
Document type:
|
Article - Published version Conference Object |
Share:
|
|