Hydraulic Structures: Fourth Edition

All methods are based on the continuity equation, in the form: I OdV/dt (4.2) whereIis the inflow, Othe outflow, and Vthe reser ...

FREEBOARD 197 Equation (4.7) applies to a free-flowing spillway without gates (for a water level in the reservoir above the cres ...

introduced to cover malfunction of the gates. A further component may be required to account for the effect of impulse waves gen ...

FREEBOARD 199 A modification of equation (4.10) includes a provision for wind speed: H0.032 (UF)1/20.76 0.24(F)1/4. (4.11) In ...

Therun-upof waves on the upstream dam face, i.e. the maximum vertical height attained by a wave running up a dam face, referred ...

SEDIMENTATION IN RESERVOIRS 201 A comprehensive guide to sedimentation in lakes and reservoirs has been published by Unesco (Bru ...

has to be used in time steps (1–10 years depending on the accuracy required), as at the end of each period the reservoir volume ...

SEDIMENTATION IN RESERVOIRS 203 The various deposition stages in a reservoir are shown schematically in Fig. 4.3. Reservoir capa ...

conventional methods, particularly a suction dredger with a bucket wheel, or special techniques (e.g. pneumatic or jet pumps) ma ...

CAVITATION 205 surface is ‘smooth’ and well constructed. (Elder reported values of absolute roughness of about 1 mm for the 5.5 ...

avoid pressures below about 7 m vacuum (3 m absolute) in hydraulic engineering design. It has to be stressed, however, that in t ...

SPILLWAYS 207 For a notch of width b, head h, and coefficient of discharge Cd, the discharge equation is Q 2 g1/2bCdh  3 ...

or yKxnH^1 n0.5x1.85H^ 0.85 (4.18b) (curve a in Fig. 4.5 (Novak and Cˇábelka, 1981)). Note that the head above the new crest ( ...

SPILLWAYS 209 sures for outflow under partially raised gates. The discharge through par- tially raised gates may be computed (Fi ...

However, the spillway may terminate in a vertical face with a free-falling jet (e.g. in arch dam spillways) or in a ski jump sha ...

SPILLWAYS 211 a free overfall over the entire horizontal spillway crest, so that the reservoir level is not influenced by the fl ...

Equation (4.24) can be solved by numerical methods, and also results in the differential equation of flow: S 0 Sf  g 2 A Q  ...

SPILLWAYS 213 dM/dxA   the scheme for numerical integration could, for two consecutive sections, be expressed as follows (Ch ...

The basic treatment of the hydraulics of shock waves can be found for example in Henderson (1966) and of design considerations i ...

SPILLWAYS 215 In this case the maximum depth at the wall yw(important for the free- board)(occurs at a distance about 1.75y 1 Fr ...