dear Rwoolhou

Thank you so much, you have helped me out a lot, so far.

would you please do me a favor and guide me on how to amend my UDF written in the following to get such outputs? (CD or drag force or any other relating issue)

let's consider the default drag UDF provided by the ANSYS website. I'd appreciate it if you give me a hint on this example.

Moreover, do you know how Re is defined in the following code? is it based on the particle velocity relative to the flow? or is it based on absolute particles' velocity?