Load from Output or Other Text File

[John_Holtz]

Inventor Nastran can apply loads to the current model using results from Autodesk CFD (pressure, temperature) or a different Inventor Nastran analysis (temperature). I would like the command to be expanded to support text files. This would allow results from other programs to be imported as loads into Inventor Nastran. (It could also be a new command instead of using "Loads > From Output".)

The workflow would be like this:

1. The user creates a text file from their other program (temperature, pressure, whatever Inventor Nastran decides to support) and the coordinate where the result it located. For example, the coordinates of a node for nodal result (such as temperature), the coordinate of an element face for element result (such as pressure on a face).
2. In Inventor Nastran,
   1. The user would select the text file.
   2. The user would specify the type of load to be applied (temperature, pressure, etc.) The types of load that can be supported needs to be determined. (Temperature and pressure would be easy because they are continuous functions. Force would not work since you cannot transfer a force that is from a 20x20 mm element and apply it to a 5 mm mesh.)
   3. The user would select where the load is to be applied to the Nastran model.
   4. Specify a multiplier for the result, usually either 1 or -1. For example, pressure from a CFD model may need to be "reversed" or multiplied by -1 to get the proper direction for a stress model. (Maybe, maybe not. We cannot predict what the user will need to do to the results.)
   5. Specify a tolerance for interpolating from the result mesh to the Nastran mesh. Since the mesh will be different, the location of the centroid of a face that has a pressure result will not be exactly in the plane of any element in the Nastran mesh. How far out of plane is acceptable?
   6. Specify what value should be applied to the Nastran model if there is a coordinate on the selected entities that does not exist in the result file. (I would assume 0 in most cases, but perhaps there are times when a different value would be used. For example, room temperature when transferring temperatures from a heat transfer model to a stress analysis.)
3. Nastran would interpolate the result file based on the coordinate of the mesh in the Nastran model and apply the load. (Think of the results as being a point cloud. Based on the node or element face in the Nastran model, the point cloud would be interpolated, and that load applied at the node or element face.)

Current "Loads From Output" interface. Expanding the capability to allow importing results from a text file could be one option.