Comparing batch runs for a single variable

Step 1: Set up the batch parameters

First we will set up a batch run to obtain some different result sets. We will vary the body mass.

Procedure

1. In Parameter mode, drag the Mass parameter from the Body mass component to the Study Manager window.

2. In the Studies tab, set the Step size to 10 with Num below and above set to 2:

Note See Using batch runs for more information about setting up batch runs.

3. Perform a batch run.

Step 2: Compare data sets

Now we can use the Post-processing tab to compare results from different data sets for a given variable. We will compare the Velocity at port 1 variable results for batch 1 and batch 5.

Procedure

1. Click on the Body mass and drag the Body velocity variable to the Post processing tab:

2. Once again, drag the Body velocity variable to the Post processing tab, and drop it onto the existing expression, selecting the subtract operation:

Now the expression is as follows:

The next step is to edit the expression to specify the two result sets we want to compare. To specify a result set to use, we add its number in square brackets [N] to a variable. In this case, we have 5 batch runs available:

We are going to compare result sets [1] and [5].

3. Edit the expression as follows: (v1@Body_Mass[1])-(v1@Body_Mass[5])Add [1] to the first variable, and [5] to the second.

Note The Default Result Set column is now disabled. This is because, with both expressions explicitly pointing to result sets, it serves no further purpose.

4. Plot the post-processing variable.