v2.02.118 SDLL118 - Beam subjected to axial fluid-elastic excitation

Summary:

We consider a PVC tube placed in the center of a cylindrical chamber with a circular cross section and subjected to the action of an axial flow of water. This hardware configuration corresponds to the experimental device of Tanaka et al. [bib1] which is used to measure the changes in frequency and reduced damping of the first mode of the tube as a function of the average flow speed.

The aim of this test case is to validate the resorption of the MEFISTEAU [R4.07.04] model making it possible to calculate the modal characteristics of a wire structure under confined axial flow, taking into account fluid-elastic type excitation.

The specific functionalities to be tested are as follows:

• operator DEFI_FLUI_STRU [U4.25.01]: definition of the parameters for taking into account fluid-elastic coupling, in the case of a configuration of the « bundle of tubes under axial flow » type (keyword factor FAISCEAU_AXIAL),

• operator CALC_FLUI_STRU [U47.66.02]: calculation of frequency changes and reduced modal damping as a function of the average flow speed, by implementing the MEFISTEAU model.

The numerical results of the simulation of the device by Tanaka et al. are validated by comparison with the experimental results. Given the relatively large uncertainties in the experimental values, the reference results for the non-regression of the code are those obtained numerically during the restoration of the test case.

• 1. Reference problem
  • 1.1. Geometry
  • 1.2. Material properties
  • 1.3. Boundary conditions and loads
  • 1.4. Bibliographical reference
• 2. Benchmark solution
• 3. Modeling A
  • 3.1. Characteristics of modeling
  • 3.2. Characteristics of the mesh
  • 3.3. Calculation steps
  • 3.4. Tested values
  • 3.5. notes
• 4. B modeling
  • 4.1. Characteristics of modeling
  • 4.2. Characteristics of the mesh
  • 4.3. Calculation steps
  • 4.4. Tested values
  • 4.5. notes