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a generic equation…
The X_pl@re platform proposes a generic type of empirical equation where the user can freely determine the following parameters and coefficients (Castillo and Carrillo, 2017):
- Y = downstream tailwater depth [m]
- K = empirical coefficient [-]
- q = specific discharge [m2/s]
- H = energy head [m]
- g = gravitational acceleration [m/s2]
- dm = average particle size of the bed material [m]
- d85 = bed material size for which 85% is smaller in weight [m]
- d90 = bed material size for which 90% is smaller in weight [m]
- a to g = coefficients to be defined [-]
…followed by simplified equations…
Based on the above generic equation, a number of so-called « simplified » scour formulae have been summarized by Castillo and Carrillo (2017). The X_pl@re platform proposes 12 of these scour formulae. The sets of parameters used by each of these formulae is given in the figure on the right-hand side.
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…and finally more general equations…
Finally, some more general equations have been implemented, applicable to free surface overfall jets or ski-jump jets:
- Jaeger (1939)
- Mirtskhulava (1967)
- Martins A (1973)
- Mason and Arumugam (1985)
- Mason (1989)
- Veronese modified by Yildiz & Uzucek (1994)
- D’agostino (1994)
- Bombardelli & Gioia (2006)