Skip to Main content Skip to Navigation
Theses

Investigation et application des méthodes d'ordre réduit pour les calculs d'écoulements dans les faisceaux tubulaires d'échangeurs de chaleur

Abstract : The objective of this thesis is to study the ability of model reduction for investigations of flow-induced vibrations in heat exchangers tube bundle systems.These mechanisms are a cause of major concern because heat exchangers are key elements of nuclear power plants and on-board stoke-holds.In a first part, we give a recall on heat exchangers functioning and on vi-bratory problems to which they are prone. Then, complete calculations leaded with the CFD numerical code Code_Saturne are carried out, first for the flow around a single circular cylinder (fixed then elastically mounted) and then for the case of a tube bundle system submitted to cross-flow. Reduced-order method POD is ap-plied to the flow resolution with fixed structures. The obtained results show the efficiency of this technique for such configurations, using stabilization methods for the dynamical system resolution in the tube-bundle case.Multiphase-POD, which is a method enabling the adaptation of POD to fluid-structure interactions, is applied. Large displacements of a single cylinder elastically mounted under cross-flow, corresponding to the lock-in phenomenon,are well reproduced with this reduction technique. In the same way, large displace-ments of a confined moving tube in a bundle are shown to be faithfully recon-structed.Finally, the use of model reduction is extended to parametric studies. First,we propose to use the method which consists in projecting Navier-Stokes equations for several values of the Reynolds number on to a unique POD basis. The resultsobtained confirm the fact that POD predictability is limited to a range of parameter values. Then, a basis interpolation method, constructed using Grassmann mani-folds and allowing the construction of a POD basis from other pre-calculated basis,is applied to basic cases.
Complete list of metadatas

Cited literature [147 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-00815992
Contributor : Abes Star :  Contact
Submitted on : Friday, April 19, 2013 - 3:52:15 PM
Last modification on : Monday, June 26, 2017 - 9:36:58 AM
Long-term archiving on: : Saturday, July 20, 2013 - 4:03:29 AM

File

2012POMAREDE29815.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-00815992, version 1

Collections

Citation

Marie Pomarède. Investigation et application des méthodes d'ordre réduit pour les calculs d'écoulements dans les faisceaux tubulaires d'échangeurs de chaleur. Autre [cond-mat.other]. Université de La Rochelle, 2012. Français. ⟨NNT : 2012LAROS355⟩. ⟨tel-00815992⟩

Share

Metrics

Record views

896

Files downloads

1540