Generalized model for interacting cylinders in Vortex Induced Vibration
PhD candidate: François Rigo
Supervisors: Vincent Denoël
Funding : FNRS (Aspirant)
Duration: 4 years (2018-2022)
Résumé du projet
The flow around bluff bodies always caught the attention of the scientific and engineering communities. Depending on the flow regime, it is characterized by flow separation and vortex shedding. When the fluid and the structure are frequency matched, the Vortex Induced Vibration (VIV) phenomenon takes place. Many aerospace, civil, wind and industrial engineering applications are concerned with this phenomenon. This is true for simple structures such as a single cylinder in a flow, for which estimating the resulting amplitude and lock-in range remains an important challenge. The complexity of the phenomenon increases when multiple bodies are concerned and interactions take place. Among other examples, heat exchangers are submitted to strong VIV interactions but only empirical models are available. Closely spaced industrial chimneys (or close to other buildings) also experience undesirable interactions. Even space rocket can be vortex excited on the launch pad or at the landing for SpaceX Falcon Heavy (three cylinders next to each other).
This research is dedicated to bring a better understanding of the VIV of single and multiple bodies in a sub-sonic flow and subcritical Reynolds range. It will rely on extensive experimental investigations feeding low-order VIV models. In particular, the three target objectives of the project are:
(i) analyze in detail the dynamics of the wake oscillation inside and outside lock-in
conditions; this will be achieved by developing an advanced experimental procedure
to assess the suitability of existing models to represent the VIV of a single body;
(ii) run an exhaustive experimental campaign to study the effect of more than one cylinder in
the flow, the influence of their shape and their interaction;
(iii)rely on the procedure developed in (i) to generalize the existing models for one cylinder
to multiple bodies interaction.
This work will bring a significant contribution to the advancement of knowledge in VIV modelling, which affects a large number of domains. As described next, the chosen scientific approach relies on the detailed observation of experiments, at fundamental level. This approach would provide a clearer picture of the phenomenon and perspectives of modelling that are complementary to Computational Fluid Dynamics (CFD) simulations or wind tunnel tests.
L’expérience a encore de beaux jours devant elle, 2019, May 06
Vortex induced vibrations of rectangular cylinders arranged on a grid, 2018, December 10
VIV response of a suspended sphere nearby the critical Reynolds number, 2018, September 10
Unsteady pressure measurement around aerodynamic bodies: Development of a calibration apparatus and wind tunnel testing, 2017, mémoire de licence/master