VELOCITY MEASUREMENTS IN CAVITATING FLOWS USING FAST X-RAY IMAGING
TypeCommunications sans actes
A promising method to measure velocity fields in complex two-phase flows such us cavitating flows is presented. Dynamics of the liquid phase and the bubbles are both investigated. The measurements are based on ultra fast X-ray imaging performed at the APS (Advanced Photon Source) of the Argonne National Laboratory. The experimental device consists of a millimetric Venturi test section associated with a transportable hydraulic loop. Various configurations of velocity, pressure, and temperature have been investigated. Radio-opaque particles are used as tracers for the liquid phase, in association with a multipixel sensor to record the successive positions of the particles. The use of X-rays instead of light solves the problems related to light reflection and dispersion on phase boundaries, since X-rays penetrate a gas/liquid flow in straight lines. Images contain simultaneously the information related to the particles (for PIV analysis in the liquid), to the vapour bubbles (for PIV in the gas). The slip velocity between vapour and liquid is calculated.
Showing items related by title, author, creator and subject.
ORTEGO, Egoï; DAZIN, Antoine; CAIGNAERT, Guy; COLAS, Frédéric; COUTIER-DELGOSHA, Olivier (TU Wien, 2012)Modelling of a hydro-pneumatic energy storage system is the main aim of this paper. The project aims to model a prototype that uses a rotodynamic multi-stage pump-turbine to displace a virtual liquid piston for air ...
CHEBLI, Rezki; COUTIER-DELGOSHA, Olivier; AUDEBERT, Bruno (2013)Cavitation is one of the most demanding physical phenomena influencing the performance of hydraulic machines. It is therefore important to predict correctly its inception and development appearance, and quantify the ...
ORTEGO, Egoï; DAZIN, Antoine; CAIGNAERT, Guy; COLAS, Frédéric; COUTIER-DELGOSHA, Olivier (SHF - Société Hydrotechnique de France, 2011)Modelling of a hydro-pneumatic energy storage system is presented in this paper. Hydro pneumatic storage aims to combine the good efficiency of hydraulic energy conversion and the space flexibility of pneumatic storage. ...
FRIKHA, Sobhi; COUTIER-DELGOSHA, Olivier; ASTOLFI, Jacques Andre (Hindawi Publishing Corporation, 2008)For numerical simulations of cavitating flows, many physical models are currently used. One approach is the void fraction transport equation-based model including source terms for vaporization and condensation processes. ...
DANLOS, Amélie; MÉHAL, Jean-Elie; RAVELET, Florent; COUTIER-DELGOSHA, Olivier; BAKIR, Farid (ASME, 2014)Instabilities of a partial cavity developed on a hydrofoil, a converging-diverging step, or in an interblade channel have already been investigated in many previous works. The aim of this study is to evaluate a passive ...