Trade-off between number of constraints and primary-statement robustness in entropy models: the case of the open-channel velocity field

This technical paper presents the genetic programming (GP) approach to predict the critical submergence for horizontal intakes in open channel flow for different bottom clearances. Laboratory data from the literature for the critical submergence for a wide range of flow conditions were used for the development and testing of the proposed method. Froude number, Reynolds number, Weber number and ratio of intake velocity and channel velocity were considered dominant parameters affecting the critical submergence. The proposed GP approach produced satisfactory results compared to the existing predictors.

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Mathematical modeling of open-channel velocity profiles for float method calibration

Agricultural Water Management ◽

10.1016/j.agwat.2004.06.008 ◽

2004 ◽

Vol 70 (3) ◽

pp. 229-244 ◽

Cited By ~ 7

Author(s):

E.Y. Kra ◽

G.P. Merkley

Keyword(s):

Mathematical Modeling ◽

Open Channel ◽

Velocity Profiles ◽

Float Method ◽

Channel Velocity

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Hydraulics of offset baffle culvert fishways

Canadian Journal of Civil Engineering ◽

10.1139/l88-137 ◽

1988 ◽

Vol 15 (6) ◽

pp. 1043-1051 ◽

Cited By ~ 13

Author(s):

N. Rajaratnam ◽

C. Katopodis ◽

S. Lodewyk

Keyword(s):

Experimental Study ◽

Velocity Field ◽

Turbulent Flow ◽

Key Words ◽

Channel Flow ◽

Open Channel ◽

Open Channel Flow ◽

Flow Equation

This paper presents the results of an experimental study on the hydraulics of culverts with offset baffles to pass fish. Using analytical considerations and experimental observations, a flow equation has been developed between the discharge, diameter, depth, and slope for a culvert fish way with the standard offset baffle system. The velocity field at the slot has also been evaluated. Some further experiments were performed to assess the effect of baffle spacing and height on the hydraulics of the culvert fishway. Key words: culverts, fishways, baffles, hydraulics, open-channel flow, turbulent flow.

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Open channel velocity profiles over a zone of rapid infiltration

Journal of Hydraulic Research ◽

10.1080/00221689109498990 ◽

1991 ◽

Vol 29 (1) ◽

pp. 15-27 ◽

Cited By ~ 44

Author(s):

A. G. Maclean

Keyword(s):

Open Channel ◽

Velocity Profiles ◽

Channel Velocity

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A depth-averaged mathematical model for the near field of side discharges into open-channel flow

Journal of Fluid Mechanics ◽

10.1017/s002211207800138x ◽

1978 ◽

Vol 86 (4) ◽

pp. 761-781 ◽

Cited By ~ 102

Author(s):

J. J. Mcguirk ◽

W. Rodi

Keyword(s):

Mathematical Model ◽

Channel Flow ◽

Open Channel ◽

Recirculation Zone ◽

Essential Feature ◽

Near Field ◽

Open Channel Flow ◽

Wide Range ◽

Channel Velocity ◽

Source Sink

A two-dimensional mathematical model is described for the calculation of the depth-averaged velocity and temperature or concentration distribution in open-channel flows, an essential feature of the model being its ability to handle recirculation zones. The model employs the depth-averaged continuity, momentum and temperature/concentration equations, which are solved by an efficient finite-difference procedure. The ‘rigid lid’ approximation is used to treat the free surface. The turbulent stresses and heat or concentration fluxes are determined from a depth-averaged version of the so-calledk, ε turbulence model which characterizes the local state of turbulence by the turbulence kinetic energykand the rate of its dissipation ε. Differential transport equations are solved forkand ε to determine these two quantities. The bottom shear stress and turbulence production are accounted for by source/sink terms in the relevant equations. The model is applied to the problem of a side discharge into open-channel flow, where a recirculation zone develops downstream of the discharge. Predicted size of the recirculation zone, jet trajectories, dilution, and isotherms are compared with experiments for a wide range of discharge to channel velocity ratios; the agreement is generally good. An assessment of the numerical accuracy shows that the predictions are not influenced significantly by numerical diffusion.

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