The International Conference on Multiphase Systems, ICMS'2000
|Paradoxes and Myths in Mechanics of Multiphase Flow|
Nigmatulin R. I.
Tyumen Institute of Mechanics of Multiphase Systems
of R. A. S., RUSSIA;
Non-reversible multiphase flows are considered when it is necessary to take into account different average fields of velocities, temperatures and pressures of the phases.
1. The relation between various popular forms of the two-fluid model is shown. The current state-of-the art in the modelling of interfacial and intraphase closure laws is summarized. New closure laws are proposed which attempt to account for the effect of dispersed phase interactions and achieve closure and well-posed models.
2. Quasi-static approximation (drift model) is considered. Non-trivial theoretical equations for slip velocity for dispersed and slug gas-liquid flows are derived. Juxtaposition of the derived equations with the Zuber-Findlay correlation is used as an experimental information to get the information on the interphase forces.
3. Some popular theoretical delusions and myths (Einstein viscosity of suspensions, Zuber & Findlay correlation interpretation, Landau sound speed in the liquids with vapor bubbles) are presented.
4. Some unusual effects in two-phase flows and in the theory are discussed. Some of them are:
5. A few non-traditional applications of multiphase systems in power, nuclear and thermonuclear, chemical, petroleum and safety engineering are discussed.