Singular losses in contractions is of interest to model, in order to compute the loss coefficent. The Navier-Stokes equations computes the enegy loss in the contraction, enabeling the determination of the loss coefficient, similar to a physical model study.
The images below are from a computation in 1994, where the flow through a gate plug was computed. Three CFD programs were used: Fluent, FIDAP and SSIIM. The results were presented at the IAHR Congress in London in 1995. The images below are from the SSIIM 1 program.
Reference:
Olsen, N. R. B. and Oldervik, O. (1995) "Three-dimensional numerical modeling of water flow through a gate plug", IAHR 26th. Biennial Congress, London.
A profile through the non-cut-off gate plug with velocity vectors. The colours shows the pressure, where red is high pressure and blue is low pressure. Note the Bernoulli effect.
A profile through the cut-off gate plug with velocity vectors. The colours shows the water velocity, where red is high velocity and blue is low velocity.
A profile throug the non-cut-off gate plug with velocity vectors. The colours shows the water velocity, where red is high velocity and blue is low velocity.
This page was last updated: 19. July 2019