I ran into a problem when trying to create a rainfall file for in HydroCAD v9.10. I want to create a 24 hour Chicago storm using a,b,c coefficients. The formula HydroCAD uses calculates depth = t*a/(b+t)^c. This is depth = time*intensity. The problem is that the a, b,c coeffs I have require t, to be in minutes, but generate an intensity in mm/hr. Therefore the t, on the top needs to be in hours, while the t on the bottom in minutes. Is it correct to adjust the a and b coeffs so that they use a t in hours? Or will this alter my Chicago storm. Or should I leave the coeffs as they are and manually input a depth when executing the rainfall file in HydroCAD. (The default depth is grossly incorrect).
Note, adjusting the coeffs allows HydroCAD to accurately provide a default rain depth.
Thanks for the help!
Note, adjusting the coeffs allows HydroCAD to accurately provide a default rain depth.
Thanks for the help!