Part of the book: Computational Fluid Dynamics
In some situations, pipe layout and incoherent behavior of the flow is detected. An instability is generated, and the flow jumps between the values in flow rate or pressure, with no explanation. Usually, the industry solves the problem by creating an exclusion area. It is very important to understand those instabilities, named bifurcation, and why the Navier-Stokes equation has two equiprobable solutions. With this knowledge, the situation can be corrected, and the problem solved. The result is an increase in performance, reliability, etc. and then in the economy of the process. The bistable flow in boiling water reactor (BWR) nuclear power plant is a clear example.
Part of the book: Boundary Layer Flows