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ounifiras October 26, 2013 22:06

problems with baffles
 
Hi, i am a new user of flow3d . I have some problems ,so I ask your help,please i have a question about the remark found in the explanation of an example of FLOW-3D (1'' define'' baffles along bottom), the problem is that I do not have inderstand the role of BAFLLES, another issue is the word bcz in the file prepin I did not find their explanation and their role in addition I can not find it in the software interface. thank you for helping me afrontir these problems


in the prepin file , the baffle definition appear as shown below:

&bf
nbafs=1,
bcz(1)=1.0,

JBurnham October 27, 2013 22:36

bcz = baffle coordinate in z. It's the z-plane the baffle is defined in. This is easily determined from the User Manual. Look in the Input Variable Summary chapter. Ctrl-F = search, use it to find bcz in that chapter. Only define one baffle coordinate definition (x, y, or z); use limiters to cut the baffle down to size.

ounifiras October 28, 2013 05:52

Quote:

Originally Posted by JBurnham (Post 459320)
bcz = baffle coordinate in z. It's the z-plane the baffle is defined in. This is easily determined from the User Manual. Look in the Input Variable Summary chapter. Ctrl-F = search, use it to find bcz in that chapter. Only define one baffle coordinate definition (x, y, or z); use limiters to cut the baffle down to size.



thank you for the explanation. can you explain the role of baffles.

dmilano November 7, 2013 17:18

Baffles are 2D surfaces used to represent thin objects without having to resolve the thickness. Also, they can serve as measurement devices, recording the flow of quantities through the baffle.

ajruggles November 8, 2013 10:47

Evaluating hydraulic energy losses and total hydraulic head with FLOW-3D baffles
 
A customer from Hydro-Quebec wrote an interesting article about using FLOW-3D baffles to evaluate hydraulic energy losses and total hydraulic head in a recent FLOW-3D newsletter. You can read it here: http://www.flow3d.com/resources/news...ulic-head.html

ounifiras November 9, 2013 08:00

Quote:

Originally Posted by dmilano (Post 461081)
Baffles are 2D surfaces used to represent thin objects without having to resolve the thickness. Also, they can serve as measurement devices, recording the flow of quantities through the baffle.

thank you for the explanation.

Yi-An Chen December 15, 2014 00:34

DEAR experts:

I set a baffle,and defined it as a flux surface "yes".
But when I save it ,"defined as a flux surface" will change to "NO" :eek:

Ican't see the Value of the discharge Q (Volume flow rate) in the Analyze->Probe->General History data:confused:

Help me, please!!

JBurnham December 15, 2014 14:09

Make sure you have only one (1) definition set. You can use Limiters to then further alter the shape. If you have only one Definition then you're using a version with a bug in it. If it's a legit version, contact Flow Science about it. If it's not a legit version try building the prepin file manually in a text editor or consider getting a real paid version.

hanif pourshahbaz July 15, 2016 07:52

3 Attachment(s)
Dear experts

i some questions and i will so grateful to any kind of answers and opinions
i used baffles to create a spur dike (groin) in channel in order to thin thickness vs channel length or width
channel is ( 174cm* 60cm* 40cm)
spur dikes are ( 30cm* 40cm* 4mm)
so i used baffles to create dikes with porosity of 0, but there are some questions,
should i turned off the define as flux surface because i read in help that:
((A flux surface is typically a 100% porous baffle with no flow losses so it does not affect the flow in any way. However, a flux surface can also be defined using a baffle that has a porosity greater than 0.0 and less than or equal to 1.0))
i want to create a solid object by baffle with a thin thickness

the second question is why i see difference object in analyses?? for example the blue one in pictures??

i attached pictures of my problems to illustrate them

Regards
Hanif

hanif pourshahbaz July 15, 2016 17:19

i have problems with baffles
i don't select flux plane to use baffles as thin walls
half of this wall is in sediment and it acts like spur dike
but when i use the FAVOR it didn't showed the part that is in sediment
what should i Do?

Thank you by the way

arkan September 10, 2016 04:23

Quote:

Originally Posted by hanif pourshahbaz (Post 609741)
i have problems with baffles
i don't select flux plane to use baffles as thin walls
half of this wall is in sediment and it acts like spur dike
but when i use the FAVOR it didn't showed the part that is in sediment
what should i Do?

Thank you by the way

decrease mesh size

hanif pourshahbaz September 10, 2016 14:33

Quote:

Originally Posted by arkan (Post 617352)
decrease mesh size

ive done it
but the baffle that is in sediment remains as nothing :D

meri95124091 November 5, 2018 17:36

baffle in probe
 
I have used the baffle to find discharge. but i want to know when we select the volume flow rate in general history, is there any difference to set data points?


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