In this thesis some fluid-structure interaction problems related to swimming are investigated. The broad domain in which the cases can be classified is that of swimming at low-Reynolds numbers, that is in conditions close to the Stokes flow. In the first part, a simpler flow configuration is considered together with an active structure, to identify possible swimming strategies arising from deformations of a multi-stable shell. After a first analysis, based on numerical simulations, an asymptotic approach is employed aiming to confirm the results analytically. In the second part a more complex flow model is considered, in order to analyze a case where the Reynolds number is small but possibly finite. The case considered is that of a robotic swimmer in a viscous fluid, inspired by a celebrated paper of Purcell which is revisited here with more modern tools, from numerical techniques to experiments. Numerical solvers are developed to simulate the related flows: particular care is devoted to the scalability and efficiency of numerical methods in order to solve the Navier-Stokes equations within acceptable time constraints. The validity and accuracy of common models for micro swimmers are assessed by comparison of numerical results with experimental results.

Fluid-structure interaction problems involving thin active shells and microswimmers / Corsi, Giovanni. - (2020 Sep 24).

Fluid-structure interaction problems involving thin active shells and microswimmers

Corsi, Giovanni
2020-09-24

Abstract

In this thesis some fluid-structure interaction problems related to swimming are investigated. The broad domain in which the cases can be classified is that of swimming at low-Reynolds numbers, that is in conditions close to the Stokes flow. In the first part, a simpler flow configuration is considered together with an active structure, to identify possible swimming strategies arising from deformations of a multi-stable shell. After a first analysis, based on numerical simulations, an asymptotic approach is employed aiming to confirm the results analytically. In the second part a more complex flow model is considered, in order to analyze a case where the Reynolds number is small but possibly finite. The case considered is that of a robotic swimmer in a viscous fluid, inspired by a celebrated paper of Purcell which is revisited here with more modern tools, from numerical techniques to experiments. Numerical solvers are developed to simulate the related flows: particular care is devoted to the scalability and efficiency of numerical methods in order to solve the Navier-Stokes equations within acceptable time constraints. The validity and accuracy of common models for micro swimmers are assessed by comparison of numerical results with experimental results.
De Simone, Antonio
Corsi, Giovanni
File in questo prodotto:
File Dimensione Formato  
phd_CORSI.pdf

embargo fino al 31/12/2021

Tipologia: Tesi
Licenza: Non specificato
Dimensione 10.2 MB
Formato Adobe PDF
10.2 MB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/20.500.11767/114355
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
social impact