Keyword(s) Pipe Internal Roughness. For a new search enter search key word(s) then click GO GO
Calculate the dimensionless relative roughness or roughness number for pipes and rectangular ducts.
`rr = (ir) / (ID) `
where :
rr = relative roughness or roughness number ir = surface roughness ID = pipe inside diameter
For rectangular ducts the hydraulic diameter is used
`ID = 2 w h / (w + h) `
ID = hydraulic diameter w = duct width h = duct height
Pipeline surface roughness and efficiency data.
Typical pipe surface roughness values, API 14E Panhandle equation efficiency factors for pipeline pressure drop, and Hazen Williams and Manning coefficients for pipeline pressure loss.