Inlet Design

[RJLDesign]

Fellow designers

I am trying to find a little progem that will give me the inlet capsities of a chamber when given the required info.

e.g.

900mm RW pit with 300mm of grate volume removed and 150mm cover.

Either in a DOS based for or excel file

any help be great

Rj

(PS. Im in australia so metric would be a benifit)