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

The Definition of the Flow Angle

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

Reply
 
LinkBack Thread Tools Display Modes
Old   December 21, 2010, 02:28
Default The Definition of the Flow Angle
  #1
New Member
 
dickyang
Join Date: Nov 2010
Posts: 2
Rep Power: 0
yangdick001 is on a distinguished road
In the document of the .mf, what is the definition of the Meridional_flow_angle, Blade-to-blade_absolute_flow_angle and Blade-to-blade_relative_flow_angle?
I read the User_Manual_cfView, find the flow angle= arctan(Vt/Vm),this definition is which one above.
Thanks
yangdick001 is offline   Reply With Quote

Old   January 25, 2011, 12:39
Lightbulb
  #2
New Member
 
sanboju
Join Date: Jan 2011
Posts: 14
Rep Power: 6
sanboju is on a distinguished road
Quote:
Originally Posted by yangdick001 View Post
In the document of the .mf, what is the definition of the Meridional_flow_angle, Blade-to-blade_absolute_flow_angle and Blade-to-blade_relative_flow_angle?
I read the User_Manual_cfView, find the flow angle= arctan(Vt/Vm),this definition is which one above.
Thanks
Hi yangdick,

I have been seen the results of the .mf document in my study case. First of all, the blade-to-blade_relative_flow angle doesn't appear.

I'm doing an unsteady simulation with a Vx flow. In all steps of the "*.mf" document appears -90 degrees for the meridional_flow_angle. I understand that angle is the angle between X axis and the normal flow axis, in my case 90. The negative symbol I think would be a sign criteria.

The flow angle you mentions (angle= arctang(Vt/Vm) in aeronautics is known as angle of attack and is the angle between the chord of the profile and the relative flow velocity (sum of upstream velocity and rotationary velocity).

In my document only appears with the merdional_flow_angle, the blade_absolute_flow_angle, so I'm not sure that would be the angle of attack because I've seen other parameters of the document and It only mentions 1 blade and I'm working with more blades. Another parameters that appear are in geometrical data (Hub_radius, Shroud_radius, ...) and the values are the domain I defined on IGG. So I'm not sure where calculate the values corresponding to the velocity, angles, etc. because I don't know the initial point of the reference axis systems, I supose It would be anti-clockwise. On the other hand, the solid is inside the rotor and I don't think that file will solve you the question of the instantaneus angle for each position.

Cheers
sanboju is offline   Reply With Quote

Old   January 25, 2011, 12:49
Lightbulb mf document
  #3
New Member
 
sanboju
Join Date: Jan 2011
Posts: 14
Rep Power: 6
sanboju is on a distinguished road
Hi again, as you see is GLOBAL RESULTS AT ROTOR/STATOR INTERFACE and not for inside blades. It means it's the transition from the rotor/stator
sanboju is offline   Reply With Quote

Old   February 23, 2011, 21:58
Default
  #4
New Member
 
dickyang
Join Date: Nov 2010
Posts: 2
Rep Power: 0
yangdick001 is on a distinguished road
Quote:
Originally Posted by sanboju View Post
Hi again, as you see is GLOBAL RESULTS AT ROTOR/STATOR INTERFACE and not for inside blades. It means it's the transition from the rotor/stator
Thank you very much!
My study case is a radial inflow turbine and I working with 1 blade.I want to analyse the loss of the turbine inlet attack angle so I must konw the definition of the flow angle clearly especially the flow angle of the turbine inlet
yangdick001 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
Compressible flow, no data at the outlet mireis FLUENT 3 Today 16:25
finding flow angle pvrao CFX 4 June 3, 2015 07:50
Slug Flow, interFoam, problems with Contact Angle PrzemekPL OpenFOAM Running, Solving & CFD 13 February 18, 2014 23:10
Modelling flow over airfoil at near stall angle Kelvin FLUENT 5 June 6, 2007 02:00
PhD in turbulence Hans Main CFD Forum 14 October 8, 2001 03:03


All times are GMT -4. The time now is 19:45.