Application of LDA to bubbly flows

Application of LDA to bubbly flows

The fluctuating velocity field in an air–water bubble column (i.d. 15.2 cm) at a gas fraction of 25% is investigated using backscatter LDA. Since the interpretation of LDA signals in bubbly flows is not straight forward also experiments on a single bubble train are reported. It is discussed that in the latter case when using seeding the backscatter LDA measures predominantly the liquid velocity...

Evolving Solitons in Bubbly Flows

At the end of the sixties, it was shown that pressure waves in a bubbly liquid obey the KdV equation, the nonlinear term coming from convective acceleration and the dispersive term from volume oscillations of the bubbles. For a variable u, proportional to -p , where p denotes pressure, the appropriate KdV equation can be casted in the form ut 6uu~ + u ~ = 0. The theory of this equation predicts...

Direct Numerical Simulation of Bubbly Flows and Application to Cavitation Mitigation

The direct numerical simulation (DNS) method has been used to the study of the linear and shock wave propagation in bubbly fluids and the estimation of the efficiency of the cavitation mitigation in the container of the Spallation Neutron Source liquid mercury target. The DNS method for bubbly flows is based on the front tracking technique developed for free surface flows. Our front tracking hy...

Numerical Simulation of Turbulent Bubbly Flows

A mathematical model for turbulent gas-liquid flows with mass transfer and chemical reactions is presented and a robust solution strategy based on nested iterations is proposed for the numerical treatment of the intricately coupled PDEs. In particular, the incompressible Navier-Stokes equations are solved by a discrete projection scheme from the family of Pressure Schur Complement methods. Nove...

Mathematical Modeling of Bubbly Flows 1