Experimental and Simulation of Dual Phase Flow in Venture Convergence-Divergence Nozzle

Abstract

In steam power plants, and high pressure high temperature water flow, phase change takes place resulting in bubbly flow. Such flow causes vibration and noise in the conduits. The present study emphasized on cavitations during a dual phase flow (water-vapor) with a variation of velocities at different conditions in converge-divergence nozzle. The investigation was carried out experimentally and numerically, by CFD simulation. A transparent material is used of PMMA in order to visualize the various regions of the flow. Furthermore, the effect of flow velocities on vibration and noise was evolved in the experimental measurements. The CFD simulation model of this problem is defining a dual compressible viscous flow with k-epsilon model for the turbulence modeling. The analyses of the simulation results and the experimental observation have been seen to be comparatively conscionable in the cavitation zone and the estimation of the throat pressure cavitations during a dual phase flow with a variation of mass transfer conditions. A model were combined with a linear viscous turbulent model for the mixed fluids in the computational fluid dynamics software. A CFD Code with modified user intervention is used to simulate steady cavitation. Some of the models were also tested using a three dimensional CFD code in configurations of cavitation on three-dimensional a converge-diverge sections. The pressure distributions and volume fractions of vapor at different cavitation numbers were simulated, which agreed well with experimental data.

Keywords

• Cavitation's
• Evaporation
• Condensation
• and Convergence –divergence Nozzle
• bubbly flow