How to add forces to flow

TomWaits · August 19, 2020, 11:52

Hi All,

I am interested in adding a force

distributed over some area in my domain over the entire simulation time. What is the best way of doing this?

There are certain fvOptions that already do a constrained version of this - take for example actuationDiskSource which applies a constant force to a circular region. I was wondering whether openfoam/any literature has generalized this to applying a non-constant force over a non-circular region.

Many thanks in advance,

Tom Waits

Ship Designer · August 19, 2020, 21:26

If the force you need to be applied acts on a boundary patch, it's probably the easiest if you convert it to pressure and choose a proper boundary condition for it. If the force is distributed over the area, maybe there's a way to use a nonuniform internalField. If the area is internal to the domain, you might need to create a baffle.

TomWaits · August 20, 2020, 06:55

Quote:

Originally Posted by Ship Designer

If the force you need to be applied acts on a boundary patch, it's probably the easiest if you convert it to pressure and choose a proper boundary condition for it. If the force is distributed over the area, maybe there's a way to use a nonuniform internalField. If the area is internal to the domain, you might need to create a baffle.

Thank you very much for your response, I will give these options a test. The area will be internal to my domain and the force will be a 2-D function.

lebc · August 24, 2020, 16:51

Hi Tom,

You may want to take a look at radialActuationDiskSource: https://github.com/OpenFOAM/OpenFOAM...tionDiskSource

It uses a radial distribution of Thrust, you can change it as you like to use your own Thrust distribution function.

Best Regards,
Luis

August 19, 2020, 11:52	How to add forces to flow	#1
TomWaits Member Tom Waits Join Date: Aug 2018 Posts: 38 Rep Power: 7	Hi All, I am interested in adding a force distributed over some area in my domain over the entire simulation time. What is the best way of doing this? There are certain fvOptions that already do a constrained version of this - take for example actuationDiskSource which applies a constant force to a circular region. I was wondering whether openfoam/any literature has generalized this to applying a non-constant force over a non-circular region. Many thanks in advance, Tom Waits

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Review: Reversed flow	CRT	FLUENT	1	May 7, 2018 05:36
Flow dependent forces	lichmaster	OpenFOAM Programming & Development	4	July 19, 2011 04:48
Add inflation on a laminar flow	xyq102296	ANSYS Meshing & Geometry	0	October 21, 2010 07:37
Forces in compressible internal flow	zabar	OpenFOAM	6	April 26, 2010 11:21
Can 'shock waves' occur in viscous fluid flows?	diaw	Main CFD Forum	104	February 16, 2006 05:44

August 19, 2020, 21:26		#2
Ship Designer Senior Member Claudio Boezio Join Date: May 2020 Location: Europe Posts: 137 Rep Power: 7	If the force you need to be applied acts on a boundary patch, it's probably the easiest if you convert it to pressure and choose a proper boundary condition for it. If the force is distributed over the area, maybe there's a way to use a nonuniform internalField. If the area is internal to the domain, you might need to create a baffle.

August 24, 2020, 16:51		#4
lebc Member Luis Eduardo Join Date: Jan 2011 Posts: 85 Rep Power: 15	Hi Tom, You may want to take a look at radialActuationDiskSource: https://github.com/OpenFOAM/OpenFOAM...tionDiskSource It uses a radial distribution of Thrust, you can change it as you like to use your own Thrust distribution function. Best Regards, Luis