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CHAPTER 6. SEDIMENT TRANSPORT MODELS
Table 6.1: Classification of coastal models (after Kamphuis 1985).
Model Class
v * d
V
P,
P
A
d
V *
Best Model (BM)
o
•
•
•
0
Lightweight Model (LWM)
•
•
°1
o
0
Densimetric Froude Model (DFM)
o
•
°1
o
0
Sand Model (SM)
o
o
•
o
o
• Satisfied
o Not Satisfied
oj Not satisfied but limited to 1.05 < ps/ p < 2.65
Maintaining the prototype-to-model ratio of each of the five dimensionless parameters results in five separate conditions of similitude:
Grain Size Reynolds Number Criterion.
Nr. =
= 1
(6.26)
Densimetric Froude Number Criterion.
N N2
nf-==1
(6'27)
Relative Sediment Density Criterion.
N
t = 1
<6-28’
Relative Length Criterion.
= 1
(6-29)
Nd
Relative Fall Speed Criterion.
N
NVu = -^ = l
(6.30)
From these scaling relationships it is possible to derive the complete scaling
requirements for each of the models listed in Table 6.1. As more of the
criteria given by Eqns. 6.26 - 6.30 are left unfulfilled, the less similar the
model will be to the prototype.