Showing 2 results for M. h. Rahimian and M. Farshchi
M. H. Rahimian and M. Farshchi,
Volume 16, Issue 2 (1-1998)
Abstract
The objective of this research is to develop an accurate numerical method to be used in showing the deformation of a liquid fuel droplet in a convective field. To simultaneously solve the internal liquid droplet flow field as well as the external gas phase flow field, a nonstaggered rectangular grid system without any coordinate transformation is used. Transition from the gas field to the liquid field is performed through consistent balancing of kinematic and dynamic conditions at the liquid-gas interface. An implicit fractional step-type method is used to capture pressure and velocity field with proper coupling at low Mach number limit. To show the accuracy of the method, the solution of the driven cavity flow and flow over a solid cylinder is presented. Next, two phase flow field solution of moving and deforming droplet in a gaseous surrounding, with appropriate surface tracking, is presented. While gas Reynolds number and Weber number are shown to play an important role in droplet deformation, liquid Reynolds number and density ratio have no significant effect.
M. H. Rahimian and M. Farshchi,
Volume 21, Issue 1 (7-2002)
Abstract
The internal flow circulation dynamics of a liquid drop moving in a co- or counter-flowing gas stream has been numerically studied. The present work is concerned with the time accurate numerical solution of the two phase flow field at the low Mach number limit with an appropriate volume tracking method to capture motion and deformation of a liquid drop. It is shown that relative velocity between gas and liquid and the parameters controlling the deformation of the drop have the strongest influence on its internal circulation, too. The effects of the liquid Weber number, ranging from 8 to 32, and of gas stream Reynolds number, ranging from 1 to 20 are studied. It was revealed that the largest and the most lasting internal circulation are observed in drops with small deformation in high Reynolds number gas streams. In the case of counter-flowing gas stream, there is a strong internal circulation inside the liquid drop. The locations of the gas separation points on the drop are strongly influenced by the internal circulation of the drop, resulting in a complex wake dynamics.
Keywords: Numerical solution, Two phase flow, Moving droplet, Droplet internal circulation
