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November 4, 2021 at 4:06 am
Ansys Employee
See 27.2.1.1. Point and Normal in the CFX-Pre User's Guide. Using the "Point and Normal" , "Location" refers to a face in the model. The origin will be at the centroid of that face with the local z axis point normal to that face. Setting a set of coordinates under Coordinate will determine the orientation of the local x axis with respect to the local z axis.
The local x-y plane will not be parallel to the global x-y plane due to orientation of the face normal. Similarly, it won't be possible to have the local x-axis be parallel to the global z-axis. To do this, use the "Axis Points" option instead of "Point and Normal" and do the following to set up the local coordinate frame:
-Determine the coordinates of the current local coordinate frame. To do this, read the .cfx file into CFD-Post and calculate the centroid coordinates by getting the area-averaged (x,y,z) on the face used in CFX-Pre for the local coordinate frame. Specify the origin in the "Axis Points" method using these coordinates
-For the "Z Axis Point", enter the origin coordinates and then perturb the z coordinate in the positive z direction
-For the "X-Z Plane Point", enter the origin coordinates and perturb the x coordinate in the positive x direction
The local x-y plane will not be parallel to the global x-y plane due to orientation of the face normal. Similarly, it won't be possible to have the local x-axis be parallel to the global z-axis. To do this, use the "Axis Points" option instead of "Point and Normal" and do the following to set up the local coordinate frame:
-Determine the coordinates of the current local coordinate frame. To do this, read the .cfx file into CFD-Post and calculate the centroid coordinates by getting the area-averaged (x,y,z) on the face used in CFX-Pre for the local coordinate frame. Specify the origin in the "Axis Points" method using these coordinates
-For the "Z Axis Point", enter the origin coordinates and then perturb the z coordinate in the positive z direction
-For the "X-Z Plane Point", enter the origin coordinates and perturb the x coordinate in the positive x direction