CAPILLARY PRESSURE - UPC

Daniel Fernàndez Garcia
UPC – Constitutive eqs.
ENERGY STATUS OF THE PORE WATER
The soil-water system has energy associated to it.
E = Energy [N-m], [Kg m 2 s -2 ]
h = hydraulic head = Energy per unit weight
h
s
= −∫
0
F(s)
m(s)
ds
E = E + E + E + ... = PV + mgz + 1/2mv
T p g c
h = E /mg = P / ρ g + z + ...
T
T
2
We can define energy in other basis. For example, in many soil
physics texts:
"Soil Water Potential" ( ψ)
ψ = Energy per unit volume (units of pressure)
s
ψ=− ρ ∫
0
(s)
F(s)
ds
m(s)
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