What is Velocity U.Beta ?

April 10, 2008, 19:46

Hi, In CFX-Post, what is Velocity U.Beta ? Thanks very much. Regards, Kushagra

April 11, 2008, 09:09

As far as I know it is the coefficient used in the spatial discretisation scheme (when it is not fixed by the user). You will find .Beta outputs for variables which are included in the transport equations (e.g. volume fractions for 2 phase flow)

latslosh.

April 13, 2008, 18:52

Hi,

The .beta variables are used in the High-resolution differencing scheme as part of its method of minimising over/undershoots.

Glenn Horrocks

visitor · May 20, 2020, 11:47

Still can't understand the meaning of this result. I have a reading on screen on; fluid. Velocity u.Beta Volume Rendering 1

Minimum value 1e-16 and maximum value 1.0.

What does this mean in terms of m/s?

Thanks
Regards

Opaque · May 20, 2020, 13:00

The values of beta has no meaning from the solution point of view.

It is the coefficient used to reconstruct the solution variable away from the nodal values

Phi_x = Phi_node + Beta * Grad(Phi).(r_x - r_node)

where r is the position vector.

Beta = 0 means there the solution is nearly constant, and no need for the gradient contribution anyways.

Beta = 1 means full contribution of the gradient.

The details are more complex, but that should be enough to get the idea.

April 10, 2008, 19:46	What is Velocity U.Beta ?	#1
Kushagra Guest Posts: n/a	Hi, In CFX-Post, what is Velocity U.Beta ? Thanks very much. Regards, Kushagra

April 11, 2008, 09:09	Re: What is Velocity U.Beta ?	#2
latslosh Guest Posts: n/a	As far as I know it is the coefficient used in the spatial discretisation scheme (when it is not fixed by the user). You will find .Beta outputs for variables which are included in the transport equations (e.g. volume fractions for 2 phase flow) latslosh.

April 13, 2008, 18:52	Re: What is Velocity U.Beta ?	#3
Glenn Horrocks Guest Posts: n/a	Hi, The .beta variables are used in the High-resolution differencing scheme as part of its method of minimising over/undershoots. Glenn Horrocks

May 20, 2020, 11:47	Meaning and interpretation of velocity u.beta	#4
visitor Senior Member AH Join Date: Apr 2014 Posts: 282 Rep Power: 13	Still can't understand the meaning of this result. I have a reading on screen on; fluid. Velocity u.Beta Volume Rendering 1 Minimum value 1e-16 and maximum value 1.0. What does this mean in terms of m/s? Thanks Regards

May 20, 2020, 13:00		#5
Opaque Senior Member Join Date: Jun 2009 Posts: 1,804 Rep Power: 32	The values of beta has no meaning from the solution point of view. It is the coefficient used to reconstruct the solution variable away from the nodal values Phi_x = Phi_node + Beta * Grad(Phi).(r_x - r_node) where r is the position vector. Beta = 0 means there the solution is nearly constant, and no need for the gradient contribution anyways. Beta = 1 means full contribution of the gradient. The details are more complex, but that should be enough to get the idea. __________________ Note: I do not answer CFD questions by PM. CFD questions should be posted on the forum.

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