Hi all,
I have to know the bend calculationsi n CAESAR. If there is a bend between three points, i have to calculate the start, end and center point of the bend by knowing the bend radius and the the points coordinates(X,Y,Z). Is there any direct way to print or list the start, end center of the bend from CAESAR, if yes how?. I need to translate the model to other CAD geometry.

The calculation of coordinates of intermediate bend nodes is performed during the analysis so they are not available from the coordinate list in input. This information is held in memory by Caesar II for performing the analysis, but it is not retained for output reporting purposes once the displacements, forces and moments, and stresses are computed. So, currently the bend intermediate nodal coordinates are not reported.

Hi, Brown
Thanks for your reply, if it is not reporting the coordinates, can you please tell me the mathematical calculations(formulas) involved. Thanks in advance,

regards
velan

You should be able to figure this one out, no? Go along the centerline of the bend to the intermediate angle specified and calculate the deltas in the rectangular coordinate system according to high school geometry and trigonometry. Or you can use the general and somewhat confusing explanation below.

First, find the plane that the bend lies in, which is defined by the direction cosines of the element going into the bend and the element going out of the bend. This plane may or may not be aligned with the Caesar II Global Coordinate System depending on the details of the geometry as defined by the user.

Now define a local x,y coordinate system centered on the origin of the radius vector. The x-axis lies along a line between the bend starting point and the origin, the positive direction faces AWAY from the bend starting point. The local y axis is in the same plane extending orthogonally to the x-axis just defined. Let the positive y-axis be parallel to the bend starting point tangent in the direction of the To Node in the element where the bend is specified. Let the beginning of the bend along the pipe centerline be point P(x,y) (x will be equal to the bend radius (-R), and y will be zero). See the attachment for clarification.

Now go to the point where the intermediate bend node is located. This is defined by an angle in the bend specification, we will call this angle Theta. Let N(x,y) be this intermediate bend node coordinate. Then use the following equation to calculate this point:

N(x,y) = P(x,y) + (R-Rcos(theta), Rsin(theta))

Now that you have N(x,y) you can relate this back to the Caesar II Global Coordinates from your definition of the local x and y axes and your relation between P(x,y) to your Global Coordinates (X,Y,Z).

thnx