scour under submarine pipelines exposed to steady flow

kjelban · January 3, 2010, 11:32

i want to build model for this phenomena (scour under submarine pipelines exposed to steady flow) and i choose FLOW-3D software to do that i just start study the software this month but i need some examples about it if anybody can help me specially about the phenomena i will be very grateful.

i want examples which can show me how to use this software.

ignatz · January 28, 2010, 13:10

Kamal, have you contacted FLOW-3D's developer, Flow Science?

miss miti · December 10, 2013, 04:03

Hi
I run my model but it doesnt show any scour, the packed sediment bed respond just like a solid material, do anyone know whats wrong with the simulation?

ignatz · December 10, 2013, 11:23

Miss Miti, where are you located? FLOW-3D has support channels all round the world. Go to here to see if there is a a representative in your country: http://www.flow3d.com/sales/sales-ma...-3d-and-mp.asp.

JBurnham · December 10, 2013, 12:13

Hi, Miss Miti. There are several reasons you might be having insufficient scour. Please try the following:

1) check the mesh resolution: there should be at least 4 cells across all solid components, and ideally there should be at least 10 cells across the most shallow flow depth.

2) check the boundary conditions: are the water free-surface elevations correct? if you are using flow rate or velocity, are they correct?

3) calibrate the sediment Critical Shields Parameter. It is best to do this with a 2-D mesh (only one cell in the 3rd direction, make sure the cell is thin so that the geometry in it is also 2-D). Vary the Critical Shields Parameter until the nearly correct scour formation is observed.

4) also in 2-D, if necessary, turn off scour entirely and get the simulation to run correctly for just water. Then turn scour back on. This is a good way to debug simulations that have problems besides the scour model.

5) check units. All your units should be consistent. If you are in SI units, for example, the sediment density should be in kg/m^e (e.g., 2650), and the sediment diameter should be in m (e.g., 0.001 for 1 mm sand).

6) do the tutorials in the User Manual and on the User Site. Consider attending a training for FLOW-3D. Contact the company that sold you the software to get more info about training, or consider asking them for support.

miss miti · December 11, 2013, 01:36

Quote:

Originally Posted by ignatz

Miss Miti, where are you located? FLOW-3D has support channels all round the world. Go to here to see if there is a a representative in your country: http://www.flow3d.com/sales/sales-ma...3d-and-mp.asp.

tnx alot But unfortunatly it dosnt support out country (Iran)

miss miti · December 11, 2013, 01:42

Quote:

Originally Posted by JBurnham

Hi, Miss Miti. There are several reasons you might be having insufficient scour. Please try the following:

1) check the mesh resolution: there should be at least 4 cells across all solid components, and ideally there should be at least 10 cells across the most shallow flow depth.

2) check the boundary conditions: are the water free-surface elevations correct? if you are using flow rate or velocity, are they correct?

3) calibrate the sediment Critical Shields Parameter. It is best to do this with a 2-D mesh (only one cell in the 3rd direction, make sure the cell is thin so that the geometry in it is also 2-D). Vary the Critical Shields Parameter until the nearly correct scour formation is observed.

4) also in 2-D, if necessary, turn off scour entirely and get the simulation to run correctly for just water. Then turn scour back on. This is a good way to debug simulations that have problems besides the scour model.

5) check units. All your units should be consistent. If you are in SI units, for example, the sediment density should be in kg/m^e (e.g., 2650), and the sediment diameter should be in m (e.g., 0.001 for 1 mm sand).

6) do the tutorials in the User Manual and on the User Site. Consider attending a training for FLOW-3D. Contact the company that sold you the software to get more info about training, or consider asking them for support.

Dear JBurnham
tnx a lot for your time and detailed reply I will check them, which out puts are better for scour? sediment height is ok?

sycst911 · February 6, 2014, 21:20

Quote:

Originally Posted by kjelban

i want to build model for this phenomena (scour under submarine pipelines exposed to steady flow) and i choose FLOW-3D software to do that i just start study the software this month but i need some examples about it if anybody can help me specially about the phenomena i will be very grateful.

i want examples which can show me how to use this software.

Kjelban,

Do you already know how to simulate pipeline scour? I sent a private email to you, but I do not get any reply from you yet. I seek your advice in this matter. Thanks a lot! ^^

January 3, 2010, 11:32	scour under submarine pipelines exposed to steady flow	#1
kjelban New Member Kamal Jelban Join Date: Jan 2010 Posts: 1 Rep Power: 0	i want to build model for this phenomena (scour under submarine pipelines exposed to steady flow) and i choose FLOW-3D software to do that i just start study the software this month but i need some examples about it if anybody can help me specially about the phenomena i will be very grateful. i want examples which can show me how to use this software. sycst911 likes this.

December 10, 2013, 04:03	scour under submarine pipeline	#3
miss miti New Member Join Date: Dec 2013 Posts: 6 Rep Power: 12	Hi I run my model but it doesnt show any scour, the packed sediment bed respond just like a solid material, do anyone know whats wrong with the simulation?

December 10, 2013, 12:13		#5
JBurnham Senior Member Jeff Burnham Join Date: Apr 2010 Posts: 204 Rep Power: 17	Hi, Miss Miti. There are several reasons you might be having insufficient scour. Please try the following: 1) check the mesh resolution: there should be at least 4 cells across all solid components, and ideally there should be at least 10 cells across the most shallow flow depth. 2) check the boundary conditions: are the water free-surface elevations correct? if you are using flow rate or velocity, are they correct? 3) calibrate the sediment Critical Shields Parameter. It is best to do this with a 2-D mesh (only one cell in the 3rd direction, make sure the cell is thin so that the geometry in it is also 2-D). Vary the Critical Shields Parameter until the nearly correct scour formation is observed. 4) also in 2-D, if necessary, turn off scour entirely and get the simulation to run correctly for just water. Then turn scour back on. This is a good way to debug simulations that have problems besides the scour model. 5) check units. All your units should be consistent. If you are in SI units, for example, the sediment density should be in kg/m^e (e.g., 2650), and the sediment diameter should be in m (e.g., 0.001 for 1 mm sand). 6) do the tutorials in the User Manual and on the User Site. Consider attending a training for FLOW-3D. Contact the company that sold you the software to get more info about training, or consider asking them for support. SJTU likes this.

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January 28, 2010, 13:10		#2
ignatz Member Join Date: Jan 2010 Posts: 39 Rep Power: 16	Kamal, have you contacted FLOW-3D's developer, Flow Science?

December 10, 2013, 11:23		#4
ignatz Member Join Date: Jan 2010 Posts: 39 Rep Power: 16	Miss Miti, where are you located? FLOW-3D has support channels all round the world. Go to here to see if there is a a representative in your country: http://www.flow3d.com/sales/sales-ma...-3d-and-mp.asp.