Formation and Propagation of Tidal Bore

Mazumder, N. C.; Bose, Somnath

doi:10.1061/(asce)0733-950x(1995)121:3(167)

Cited by 12 publications

(3 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The two types of variation present different features and a linear decay can be considered as a first approximation to the exponential decay. Note also that according to Mazumber and Bose (1995), "tidal rivers generally taper at an exponential rate", and data for Hugli River, India agree with this statement very well, providing l 0 = 21.5km, κ l = 2.7 · 10 −5 m −1 . We present in Table 3 the expressions for the dispersion coefficient B obtained for the different types of variation.…”

Section: Bore Disintegration Into Kdv Solitonsmentioning

confidence: 58%

Bore formation, evolution and disintegration into solitons in shallow inhomogeneous channels

Caputo

Stepanyants

2003

Nonlin. Processes Geophys.

View full text Add to dashboard Cite

Abstract. The propagation of nonlinear surface waves in channels of smoothly variable in space cross section is studied theoretically and by means of numerical computations. The mathematical model describing wave evolution is based on the generalized Korteweg-de Vries equation with additional terms due to spatial inhomogeneity and energy dissipation. Specifically we consider channels of variable depth and width. The breaking of Riemann waves and the disintegration of hydraulic jumps into trains of solitons have been examined. The results obtained can be useful in particular for the understanding some peculiarities of bore (mascaret) formation, viscous evolution and disintegration into solitons in inhomogeneous channels or rivers.

show abstract

Section: Bore Disintegration Into Kdv Solitonsmentioning

confidence: 58%

Bore formation, evolution and disintegration into solitons in shallow inhomogeneous channels

Caputo

Stepanyants

2003

Nonlin. Processes Geophys.

View full text Add to dashboard Cite

show abstract

“…Concerning the formation of the bore, Mazumder and Bose (1995) proposed a theory linking the appearance of tidal bores and the tidal asymmetry. They verified their theory by applying it successfully to tidal bores in the Hooghly River.…”

Section: Ii22 Fields Measurementsmentioning

confidence: 99%

Effects of tidal bores on turbulent mixing: a numerical and physical study in positive surges

Simon

View full text Add to dashboard Cite

Tidal bores are positive surges created by the flooding of tides inside estuaries and rivers. They propagate upstream in an estuary sometimes as several metre high waves. Tidal bores are fascinating phenomenon with some impact on the wildlife, the mixing and re-suspension of sediments, and river constructions. Field studies remain challenging due to the violent nature of some bores. Herein, the hydrodynamics of tidal bores was investigated in a complementary study with experimental measurements and numerical simulations of idealised models of tidal bores. While laboratory experiments offer an accurate way to measure the flow properties, numerical simulations provide rather detailed information on the hydrodynamics of bores. These simulations require detailed experimental data to accurately replicate the experiments and validate the numerical methods.Investigations were conducted at the University of Queensland in a large rectangular channel partially covered by a fixed gravel bed. The steady flow condition properties were investigated using a Pitot tube and acoustic Doppler velocimeters (ADVs). The unsteady flow conditions were obtained by the fast closure of a downstream gate, which led to an upstream propagating bore. Free surface characteristics were studied for several types of bores, from undular to breaking. Those measurements showed large free surface fluctuations during the bore passage in agreement with earlier findings. Velocity measurements were conducted at high frequency (200 Hz). In breaking bores, the ensemble averaged data exhibited large velocity reversals near the bed beneath the bore front and in its wake, whereas, in undular bores, a lesser deceleration was observed. The vertical velocity data trend closely followed the water depth time derivative for both breaking and undular bores. Overall, the velocity measurements displayed large velocity fluctuations during the passage of the bore which were believed to induce strong turbulent mixing. The turbulence was further investigated by a two point correlation technique to estimate both turbulent integral time and length scales. The turbulent integral length scales values were similar in the steady and unsteady flows, whereas the turbulent time scales were larger in the unsteady flow. The experiments were limited by the instrumentation since the ADV systems interacted with each other and lacked accuracy for measurements performed in the near vicinity of physical boundaries.A numerical investigation was then performed using the computational fluid dynamics (CFD) ii code Thétis developed in the I2M laboratory of the Université de Bordeaux. Numerical simulations reproduced experiments performed in laboratory prior to this study (Chanson, 2010a,b). The fluid was modelled by the Navier-Stokes equations in their incompressible two-phase form. The turbulence model used a large eddy simulation and the interface air-water was tracked by using a volume of fluid model. Two dimensional and three dimensional simulations were performed to study the comp...

show abstract

“…This factor is particularly a problem in certain scenarios such as tidal bores (e.g. Mazumder & Bose 1995) and coincidences of astronomical tide and storm surge. Manning's formula is commonly used to represent flow resistance (e.g.…”

Section: Introductionmentioning

confidence: 99%

A river stage correction approach using Fourier series

Zhang

Bao

2012

Hydrology Research

View full text Add to dashboard Cite

One-dimensional hydrodynamic models based on the Saint-Venant equations (the SVN model) are used widely for river stage prediction. Errors that originate from simplifying assumptions, improper specification of initial and boundary conditions, uncertainty in parameters, channel geometry, observed data, and solution methods produce the inconsistencies between actual flow and that represented by the SVN model; this problem is especially apparent in tidal rivers. All of these simplifications and sources of imprecision can accumulate and introduce substantial errors in application. Total errors due to the causes mentioned above are treated as an error function, which is introduced as an additive term in the SVN model momentum equation. The function is constructed using a Fourier series approximation of discrepancies between simulated and observed flow. By combining the SVN model with the error function, a river stage correction approach (the ISV model) isproposed to take account of unconsidered errors in application. The tidal reach of the Qiantang River is selected as the study case and results based on a classification of flood events show that the ISV model generally performs better than the SVN model alone. It indicates that the approach could help guide improvements on the SVN model performance.

show abstract

Formation and Propagation of Tidal Bore

Cited by 12 publications

References 2 publications

Bore formation, evolution and disintegration into solitons in shallow inhomogeneous channels

Bore formation, evolution and disintegration into solitons in shallow inhomogeneous channels

Effects of tidal bores on turbulent mixing: a numerical and physical study in positive surges

A river stage correction approach using Fourier series

Contact Info

Product

Resources

About