Use area formulas to calculate dimensions for features in Properties

[roy.conrad2KRX2]

Hello everyone,

I am designing a part and I want to have the desired area of a ring surface control the dimensions that define the dimensions of other conical and cylindrical surfaces. I can make the math work out in excel, but I wanted to see if I could keep the calculation inside of Inventor. I'm having an issue with something as simple as Pi*R^2...Inventor seems to be expecting units but all I can choose for area is circular mills. Does anyone have any guidance here? I'm self-taught at this so I might be missing something simple.

If all else fails I will just do my calculations in inventor and manually transfer data from program to program.

Thanks,

Roy Conrad

image.png

[JDMather]

Attach *.ipt file here.

Attach the *.XLS too for reference of intent.

[johnsonshiue · Accepted solution]

Hi! I believe you have inconsistent unit. The Area parameter has inch unit while the expression generates an inch square value. Change the parameter unit to in*in. Or change the expression to be unitless like, (A_D/1 in).

Many thanks!

[roy.conrad2KRX2]

Please see the attached files. My spreadsheets tend to be a bit chaotic, so I apologize in advance. This is a pretty fluid process as of yet.

Excel:

Basically the "flow velocity, ft/sec" formulae (G35-G39) and the "conical flow area" formulae (ex. D53) will be combined in the "axial distance between sections" cells (ex. D52) to iteratively adjust the "axial distance between sections" (ex. D52) values until "flow velocity, ft/sec" (G35-G39) equals the "linear accel. tgt." (H35-H39).

Right now I am adjusting A_d, A_D, E_d and E_h, to generate my mean gas path, updating the drawing, then manually entering d17, d18, d19, d21, d20, and d22 back into excel. I then adjust the "axial distance between sections" values until the calculated areas generate the flow velocities that match design targets, then take the manually corrected "axial distance between sections" values and enter them into B_h, C_h, and D_H, which then update the surfaces.

The easy version is the blue cells get manually entered from inventor and the orange cells get entered back into inventor.

This may be quite a long question, but all I'm trying to get from the group is the A_Area formula in parameters to work and I think @johnsonshiue 's suggestion about in*in is going to work. I'll build as much of the calculation as I can into the ipt.

Thanks,

Roy Conrad