Numerical investigation of cavitating flow in variable area venturi on the basis of experimental data

Download
2019
Gümüşel, Hasan Tolg
Variable area cavitating Venturi is a throttling device that can regulate the flow rate used in liquid and hybrid rocket motors. It has a pintle mechanism which adjusts the flow area by moving back and forth in the direction parallel to the outflow from the Venturi. The flow rate is independent of the downstream pressure due to cavitation. This makes the variable area cavitating Venturi a very critical component for liquid propellant rocket engine because it can create an isolation between the inlet and the outlet in addition to controlling the mass flow rate. In this thesis, the cavitating flow through the variable area Venturi is investigated both experimentally and numerically. In order to solve the multi-phase flow, the open-source OpenFOAM software has been utilized. Schnerr-Sauer mass transport method is used to model the cavitation together with k-omega SST turbulence model. The model and the solver have tried to be verified and validated by experimental studies conducted on a simple version of the cavitating Venturi. The pintle positions, the upstream and downstream pressures, and the divergence angle of the Venturi has been examined in terms of their effect on the Venturi performance.

Suggestions

Design and analysis of a vertical axis water turbine for river applications using computational fluid dynamics
Demircan, Eren; Aksel, Mehmet Haluk; Pınarcıoğlu, Mehmet Melih; Department of Mechanical Engineering (2014)
The main purpose of this study is to design a Darrieus rotor type vertical axis water turbine using Computational Fluid Dynamics (CFD) in order to be used in river currents. The CFD modeling is based on two dimensional numerical solution of the rotor motion using commercial Unsteady Reynolds Averaged Navier-Stokes solvers, Ansys Fluent and CFX. To validate the two dimensional numerical solution, an experimental Darrieus rotor type water turbine from literature is studied and performance of several turbulenc...
Numerical & experimental investigation of flow through a cavitating venturi
Yazici, B.; Tuncer, İsmail Hakkı; Ak, M. Ali (2007-06-16)
Cavitating venturies are one of the simplest devices to use on a flow line to control the flow rate without using complex valve and measuring systems. It has no moving parts and complex electronic systems. This simplicity increases the reliability of the venturi and makes it a superior element for the military and critical industrial applications. Although cavitating venturis have many advantages and many areas of use, due to the complexity of the physics behind venturi flows, the characteristics of the ven...
Numerical investigation of the effect of the Rushton type turbine design factors on agitated tank flow characteristics
Yapici, Kerim; Karasözen, Bülent; Schaefer, Michael; Uludağ, Yusuf (2008-08-01)
The turbulent flow field in a mixing tank generated by the six-blade Rushton turbine impeller is predicted by using computational fluid dynamics. The governing differential equations of the fluid flow are approximated by an algebraic set of equations through a finite volume method, while large eddy simulation is employed to handle the effects originating from the turbulence. The relative motion between the rotating impeller and the stationary baffle is considered by clicking mesh method. The effects of impe...
Computational fluid dynamics simulation of the combustion process, emission formation and the flow field in an in-direct injection diesel engine
Barzegar, Ramin; Shafee, Sina; Khalilarya, Shahram (National Library of Serbia, 2013)
In the present paper, the combustion process and emission formation in the Lister 8.1 in-direct injection diesel engine have been investigated using a computational fluid dynamics code. The utilized model includes detailed spray atomization, mixture formation and distribution model which enable modeling the combustion process in spray/wall and spray/swirl interactions along with flow configurations. The analysis considers both part load and full load states. The global properties are presented separately re...
Incompressible flow simulations using least squares spectral element method on adaptively refined triangular grids
Akdağ, Osman; Sert, Cüneyt; Department of Mechanical Engineering (2012)
The main purpose of this study is to develop a flow solver that employs triangular grids to solve two-dimensional, viscous, laminar, steady, incompressible flows. The flow solver is based on Least Squares Spectral Element Method (LSSEM). It has p-type adaptive mesh refinement/coarsening capability and supports p-type nonconforming element interfaces. To validate the developed flow solver several benchmark problems are studied and successful results are obtained. The performances of two different triangular ...
Citation Formats
H. T. Gümüşel, “Numerical investigation of cavitating flow in variable area venturi on the basis of experimental data,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Mechanical Engineering., Middle East Technical University, 2019.