Is anyone aware of a relatively "simple" program (Excel, Mathcad,Dos-based) that will solve for Rip-Rap size and/or design of Conduit outlet protection? this is primarily for purposes of Soil Erosion and Sediment Control.
try US Bureau of Reclamation, "Hydraulic Design of Stilling Basins and Energy Dissipaters" Figure 165 is a simple chart - enter with velocity and it gives the required stone diameter / weight.
Actually, I did find something just the other day.
There are actually a few good spreadsheets in excel format that I found for Detention design, Channel design, culvert design, etc.