CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > FLUENT

Reference Values for Troughs @ variable Angle?

Register Blogs Members List Search Today's Posts Mark Forums Read

Reply
 
LinkBack Thread Tools Display Modes
Old   August 13, 2009, 13:17
Default Reference Values for Troughs @ variable Angle?
  #1
New Member
 
Join Date: Aug 2009
Posts: 12
Rep Power: 8
hornig is on a distinguished road
hi there,

I need some help of you expertes .
I did 2d-meshes of parabolic troughs at certain angles (0,30,60,90,190 degrees) and let fluent do its magic.

to illustrate, what it looks in basic I added a picture.
I just need a crossection of this parabolic trough and I put in this for reference values.

depth=12m
length=6m=apterture
area=depth*length=72m
and the rest was left in default setting.

so, the problem is, that the pressure coefficients are near their estimated area, except the 0 one (the open area is vertical upwards). this value is so far of, that I don't know, what I did wrong.
I chacked the 180 one and this is okay.

so I'm pondering, where the error is. I print the forces and stuff by "report->forces->x/y"

so my guess is, that something is wrong with the reference values. the given values are used for all angle-modes, but I din't know for sure, it the length for example will change. and the area is, as far as i know, the projected area from velocity direction, so that would make the area in image #1 Area=length*depth, but Area=height*depth in image #2.
and what is, when there are different angles, like in #4?

so, could someone please help me with this? I don't find it in the manuals.

thank you in advance!

hornig is offline   Reply With Quote

Old   April 12, 2014, 22:26
Default wind load on parabolic trough
  #2
New Member
 
bassem
Join Date: Apr 2014
Posts: 6
Rep Power: 3
kaabya is on a distinguished road
hi there,

I need some help of you expertes .
I am studying wind load on a parabolic solar concentrator at certain angles using Fluent.

I choose to start with the 2D simulation in order to evalate the drag and lift coefficient.

I have some troubles :

1. I don't find a logical drag coefficient value. It seems related to the references values. How can I set up those values in my case ?

2. If the 2D simulation is sufficient to find a good results ?


Thank you for advance

Bassem
kaabya is offline   Reply With Quote

Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Angle variable under CEL. Gloria Gaynor CFX 11 November 26, 2012 07:29
Error with Wmake skabilan OpenFOAM Installation 3 July 28, 2009 00:35
G95 + CGNS Bruno Main CFD Forum 1 January 30, 2007 01:34
Two-Phase Buoyant Flow Issue Miguel Baritto CFX 4 August 31, 2006 12:02
reference on surface tension and the contact angle Xicheng Jia Main CFD Forum 3 August 25, 2003 14:57


All times are GMT -4. The time now is 19:14.