Speaker:

Kehinde O. Ladipo, University of Houston

Title:

Finite Element Analysis of Fluid motion in Conical Diffusers

Abstract:

A finite element analysis of the flow of an incompressible Newtonian
fluid through a conical diffuser is presented. Time discretization of
the equations of motion by three-operator splitting is combined with
the wave-like-equation method of treating advection. The effect of the
diffuser-included angle on the fluid motion is investigated. The
objective of this work is to develop an efficient finite element model
for conical diffusers and use the model to determine the optimal
diffuser-included angle that will eliminate (or reduce to a negligible
level), the re-circulation region that usually develops behind the
smaller diameter pipe. The re-circulation is as a result of flow
separation which also translates to pressure losses across the
diffuser.

Results are presented for the numerical simulation using
diffuser-included angles q = 28.08 degrees and 22.60 degrees, and
diffuser-diameter ratio 1.5.  Plots of the streamlines and velocity
contours, as well as the horizontal velocity profile revealed the
expected re-circulation region when the included diffuser angle is
large. The length of the re-circulation region, determined from the
streamlines and contour plots, provided a prediction of the
appropriate range of included angles that can eventually be applied to
model a diffuser that will be re-circulation free.