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fadly July 16, 2007 23:43

polynomial curve in CFD workbench
can we make polynomial curve and then extrude it in the ANSYS Workbench??let say i want to make 5th order can i make it??thanx...

Prachi July 19, 2007 03:06

Re: polynomial curve in CFD workbench
My best guess would be to put the equation in excel and generate a couple points. Then you can use the create points utility to read a *.txt file to read them. Make a polyline of the points adn then extrude it. Hope it helps


fadly July 19, 2007 05:36

Re: polynomial curve in CFD workbench
thanx...exactly i want to make a axismmetric contraction shape using polynomial equation.what do you mean by generate a couple points??I've made an equation in can i put all the points in the design modeler??

Prachi July 19, 2007 06:13

Re: polynomial curve in CFD workbench

If you ahve the explicit co-ordinates. here is how you can generate them in workbench

Coordinates File This option allows you to specify a text file from which to read coordinates. These coordinates are used exactly as specified and are not projected onto any face or edge. The file itself must be a simple text file formatted according to the following rules:

After a pound sign '#,' everything else on that line is considered a comment and is ignored.

Empty lines are ignored.

Data consists of 5 fields, all on one line, separated by spaces and/or tabs:

Group number (integer): must be >0

Id number (integer): must be >0

X coordinate

Y coordinate

Z coordinate

A data line with the same Group and Id numbers as a previous data line is an error.

Number of points is limited to the value set in the Options dialog box (see the Point Feature Limit setting under the DesignModeler Miscellaneous settings in the Options dialog box).

The Refresh property for this option allows you to update your text file and have the system read it again. Since the Group number and Id number fields uniquely identify each point generated for this Point feature, this allows you to modify coordinates, or delete or add points. A sample coordinates file is shown below.

# List of Point Coordinates

# Format is integer Group, integer ID, then X Y Z all # delimited by spaces, with nothing after the Z value.

# Group 1 1 1 20.1234 25.4321 30.5678 1 2 25.2468 30.1357 35.1928 1 3 15.5555 16.6666 17.7777

#Group 2 2 1 50.0101 100.2021 7.1515 2 2 -22.3456 .8765 -.9876 2 3 21.1234 22.4321 23.5678

I hope this helps. Prachi

Talha July 19, 2007 23:40

Re: polynomial curve in CFD workbench

I think Prachi is right this is one approach, but i was wondering if there was a way to give the coordinates implictly, means that give the value of x and y will be calculated from the expression ie x=Ay**5+By**4+c and A,B,C can be used as parameters for optiisation,so that i can optmise the curve of converging area of nozzle.


Prachi August 2, 2007 05:07

Re: polynomial curve in CFD workbench

I am not aware how one could do it in the way Talha suggested. It would be awesome for optimisation studiesif it can be done.

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