I believe the mod you are looking for is called
Enhanced damage effects.
This would be a good place to look.
https://www.subsim.com/radioroom/dow...p?do=cat&id=17
I hope this may help in your search.
Edit: Found it.
https://www.subsim.com/subsim_files/...s2005_sh3.html
Real Damage Mod For 1.3 and New DC/Sonar Fix
Just click on the link and it will be downloaded or go to the link for a description.
Click on Silent Hunter 3 and scroll down to the heading above.