Interaction between a bubbly flow and a moving obstacle

N. Chikhi (1, 2) , Sylviane Pascal-Ribot (1, 2)

1 CEA-DES (ex-DEN) - CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire)
2 DTN - Département Technologie Nucléaire

The present paper investigates the interaction between a bubbly flow and an obstacle (sphere or cylinder). The goal is to calculate the force exerted by the bubbly flow on a transverse obstacle. To do this, the bubbly fluid is described with the help of the Kogarko, Iordanski and Van Wijngaarden model. The flow is assumed to be potential. The resolution of the motion equations leads to a 'wave equation' satisfied by the velocity potential. Coupled with the boundary conditions, we solve this equation in two situations. First, in permanent regime, we prove that the force exerted on the obstacle is equal to zero, generalizing the d'Alembert paradox. Second, we consider the harmonic vibrations of the obstacle. Then, we derive an analytic expression of the force which is the sum of two terms, the added mass and a friction force due to the compressibility of the gas bubbles. More, we prove that this force increases with the void fraction.

Keywords: Fluid-structure interaction; bubbly fluid; acoustic approximation

Domains: Nuclear Experiment [nucl-ex]; Nuclear Theory [nucl-th]

N. Chikhi, Sylviane Pascal-Ribot. Interaction between a bubbly flow and a moving obstacle. ICONE-15, Apr 2007, Nagoya, Aichi, Japan. ⟨cea-02355366⟩