Equations

Select an Equation:
Title Equation Application
Manning Q = (1.486 / n) * A * R ^ (2 / 3) * S ^ (1 / 2) General
Chezy v = c * sqrt(r * s) General
Darcy-Weisbach v = sqrt((8 * g / f) * R * S) Typically used for pipe flow
Strickler n = 0.034 * d_50 ^ (1 / 6) Gravel-bed rivers in Switzerland
Meyer-Peter, Mueller n = 0.032 * d_90 ^ (1 / 6) Sand mixtures in flumes
Lane-Carlson n = 0.039 * d_75 ^ (1 / 6) Canals lined with cobbles
Limerinos n = (0.0927 * R ^ (1 / 6)) / (0.035 + 2.03 * log_10(R / d_50)) Gravel-bed rivers in California
Bray n = 0.048 * d_50 ^ 0.179 Gravel-bed rivers in Alberta, Canada
Bray n = 0.126 * R ^ (1 / 6) * (R / d_50) ^ -0.281 Gravel-bed rivers in Alberta, Canada
Bray n = (0.0927 * R ^ (1 / 6)) / (0.248 + 2.36 * log_10(R / d_50)) Gravel-bed rivers in Alberta, Canada
Griffiths n = (0.0927 * R ^ (1 / 6)) / (0.76 + 1.98 * log_10(R / d_50)) Gravel and cobble bed rivers in USA, Canada, New Zealand, and England
Griffiths n = 0.104 * R ^ (1 / 6) * (R / d_50) ^ -0.297 * (P / R) ^ -0.103 Gravel and cobble bed rivers in USA, Canada, New Zealand, and England
Jarrett n = 0.39 * S ^ 0.38 * R ^ -0.16 Steep streams in CO with cobbles and small boulders
Froehlich n = 0.245 * R ^ 0.14 * (R / d_50) ^ -0.44 * (T / R) ^ -0.30 Gravel and cobble bed rivers in USA
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Page Last Modified: Wednesday, 30-Jan-2008 10:02:55 CST