standard and sensibility design studies

[olivierpa]

DearAll


I'm working with Wildfire 4 and I want to know the stategy to use with sensivity design, did I have to use first local sensivity and then globale sensivity , or the opposite


I also don't see what is the utility of the standard design study .


whit this study I can set parameter with basic dimension and setting but in the window of results I don't have access to this pararmeterso why set a parameter you can't use


Many thanks for your help

 

[olivierpa]

Dear all


Seams my question is a stupid question , anyway if one of you can take some times to answer me , it will be great


Many thanks for your help





Olivier

 

[srieger]

Sensitivity study is used to determine how sensitive selected parameters or dimensions are to meeting your objectives. This way, you can concentrate on only the parameters and dimensions that matter the most.

 

[srieger]

The design study is to analyze various design modifications based on defined criteria. Setting specific limits for dimensions and parameters and evaluating the effects on the design based on the desired goal criteria.

 

[indigo2]

There are two types of sensitivity studies: Local and Global.
First the Global version: It is used to evaluate the effect of changing a parameter over the entire range. For example, imagine a plate with a hole in it. If you want to see the effect (on stress or displacement, for example) of changing the hole's diameter from 2 mm to 10 mm, you would use the GLOBAL sensitivity study. You'd set the parameter corresponding to the hole diameter as the value you want to investigate. You'd set the minimum to 2, and the maximum to 10. You should use the shape animate function to ensure that the model will regenerate over the range you just specified.

Next, let's talk about the LOCAL sensitivity study. In this case, you'll set the hole diameter to some discrete value, say 4.25. This will give you results that are accurate in the neighborhood (like +/- 1%) of 4.25.

You'll look at the slope of the graph(s) that is (are) created in the results, and determine which parameters are significant.

SO, having said all of that, the final answer is, start with the LOCAL sensitivity study, with your best guess as to starting points for the parameters. Check the results, and weed out the parameters that don't affect the model's performance. Then, use those parameters in a OPTIMIZATION or a standard study. The GLOBAL sensitivity study allows you to see the overall impact of changes of a specified parameter.

The standard study lets you run a study at a particular set of parameter values without going back into part / assembly mode, changing the values, regenerating, and then going back into Mechanica.

Hope that helps.
-tsl




Edited by: indigo2

 

[olivierpa]

Dear All


Many thanks for your explanation , now I have a better of what I have to do


Olivier