To run a COMSOL Multiphysics batch job from the COMSOL Desktop, you need to make the Batch feature visible: in the Model Builder tree, click the Show More Options button () and select Batch and Cluster in the Show More Options dialog. In the Model Builder, right-click a Study node and select Batch to create batch jobs.

From a terminal window, you can start batch jobs using the comsol batch command. This is an example of such a command:

To run a specific study add the command line option -study <tag>, where <tag> is the tag of the study to run, for instance, std1. To see the tag, click the toolbar button Model Tree Node Text in the Model Builder and select Tag.

The COMSOL Multiphysics Reference Manual has a dedicated section on running COMSOL Multiphysics from a terminal window, including a list of COMSOL commands and associated syntax.