Water Hammer and Hydrodynamics’ Instability - Advances in Control and Automation of Water Systems - page 61

4

Water Hammer and
Hydrodynamics'
Instability

contents

4.1 Introduction .....................................................................................................................62
4.2 Materials and Methods .....................................................................................................63
4.2.1 Modeling and numerical simulations of water hammer .......................................66
4.2.2 Structure ................................................................................................................71
4.3 Results and Disscusions....................................................................................................72
4.3.1 Regression modeling results has been compared with research Field
Tests Model ......................................................................................................................72
4.4 Conclusion ........................................................................................................................79
Keywords ...................................................................................................................................80
References ..................................................................................................................................80

nomenclAtures
λ = coefficient of combination, w = weight

t = time, λ ۪ = unit of length

V = velocity

ρ1 = density of the light fluid (kg/m3),

ρ2 = density of the heavy fluid (kg/m3), C = surge wave velocity in pipe

s = length, f = friction factor

τ = shear stress, H2-H1=pressure difference (m-H2O)

C=surge wave velocity (m/s), g=acceleration of gravity (m/s²)

v2-v1=velocity difference (m/s), V =volume

e=pipe thickness (m), Ee=module of elasticity(kg/m²)

K=module of elasticity of water(kg/m²), θ = mixed ness integral measure

C=wave velocity(m/s), σ = viscous stress tensor

u = velocity (m/s), c = speed of pressure wave (celerity-

m/s)

D = diameter of each pipe (m), f = Darcy-Weisbach friction factor

θ = mixed ness integral measure, µ=fluid dynamic viscosity(kg/m.s)

R=pipe radius (m²), γ= specific weight (N/m³)