CHAPTER 2
CIRCULATION MODEL
2.1 Governing Equations
The governing equations for the circulation model are the depth integrated time aver
aged horizontal equations of momentum
dU TTdU dU dfj 1 1
aT + uli + + 9al+ jDr ~ jDr-
+
J_ (dstx asxv\ 1 drl =
pD \ dx dy ) p dy
dV TJdV SV dfj 1 1
aT + 0 + v 87+3 J-y + Td'1' Jdt-
dx
+
_i_ = 0
pD \ dx dy ) p dx
(2.1)
(2.2)
and the continuity equation
(2.3)
where
U = x component of the mean current
V = y component of the mean current
fj = mean water surface elevation
p = water density
D = the total water depth = h0 + fj
h0 = local still-water depth
rj = the lateral shear stress due to turbulent mixing
Tix = x component of the bottom shear stress
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