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Commit 604b6737 authored by Dorchies David's avatar Dorchies David
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doc(macrorugo): reference for r values

Refs jalhyd#283
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......@@ -136,14 +136,12 @@ For the cylindrical form of the blocks, \(\sigma\) is equal to \(\pi / 4\) and f
### Ratio between the average speed downstream of a block and the maximum speed *r*
Cassan et al. (2014) [^2], Table 2 gives experimental measurements of this ratio for cylindrical blocks (\(r=1.2\)), rounded faces (\(r=1.2)\) and flat faces (\(r=1.5\)).
The value of this ratio is (\(r=1.1\)) for cylindrical blocks (Tran et al. 2016 [^3]), and (\(r=1.5\)) for flat-faced blocks (Cassan et al. (2014)[^2], Table 2).
The formula used in Cassiopeia allows to take into account shapes of intermediate blocks between circular and square shapes from the values of \(C_{d0} = 1.1\) for cylindrical blocks and \(C_{d0} = 2.6\) for blocks with flat faces:
$$ r = (C_{d0} *0.4 + 1.121) / 1.5 $$
We now have \(r = 1.1\) for circular blocks and \(r = 1.35\) for flat-faced blocks.
### Froude *F*
$$F = \frac{V_g}{\sqrt{gh}}$$
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......@@ -133,7 +133,7 @@ On a donc \(\sigma = \pi / 4\) pour un bloc circulaire et \(\sigma = 1\) pour un
### Ratio entre la vitesse moyenne à l'aval d'un block et la vitesse maximale *r*
Cassan et al. (2014)[^2], Table 2 donne des mesures expérimentales de ce ratio pour les blocs cylindriques (\(r=1.2\)), aux faces arrondies (\(r=1.2)\) et aux faces planes (\(r=1.5\)).
La valeur de ce ratio est de (\(r=1.1\)) pour les blocs cylindriques (Tran et al. 2016 [^3]), et (\(r=1.5\)) pour les blocs à faces planes (Cassan et al. (2014)[^2], Table 2).
La formule utilisée dans Cassiopée permet une prise en compte de formes de plots intermédiaires entre les formes circulaire et carré à partir des valeurs de \(C_{d0} = 1.1\) pour les blocs cylindriques et \(C_{d0} = 2.6\) pour les blocs à faces planes :
......@@ -223,6 +223,10 @@ $$C_f = \frac{2}{(5.1 \mathrm{log} (h/k_s)+6)^2}$$
- \(z_0\) : rugosité hydraulique (m)
- \(\tilde{z}\) : position verticale adimensionnelle \(\tilde{z} = z / k\)
[^1]: Cassan L, Laurens P. 2016. Design of emergent and submerged rock-ramp fish passes. Knowl. Manag. Aquat. Ecosyst., 417, 45
[^1]: Cassan L, Laurens P. 2016. Design of emergent and submerged rock-ramp fish passes. Knowl. Manag. Aquat. Ecosyst., 417, 45. https://doi.org/10.1051/kmae/2016032
[^2]: Cassan, L., Tien, T.D., Courret, D., Laurens, P., Dartus, D., 2014. Hydraulic Resistance of Emergent Macroroughness at Large Froude Numbers: Design of Nature-Like Fishpasses. Journal of Hydraulic Engineering 140, 04014043. https://doi.org/10.1061/(ASCE)HY.1943-7900.0000910
[^3]: Tran, T.D., Chorda, J., Laurens, P., Cassan, L., 2016. Modelling nature-like fishway flow around unsubmerged obstacles using a 2D shallow water model. Environmental Fluid Mechanics 16, 413–428. https://doi.org/10.1007/s10652-015-9430-3
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