A weighting function model for unsteady open channel friction

Zhou, Junwei; Bao, Weimin; Tick, Geoffrey R.; Moftakhari, Hamed; Cao, Qing; Ye, Fanghong

doi:10.1080/00221686.2021.2004251

Cited by 2 publications

(1 citation statement)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To overcome this shortcoming, a wide range of friction models are proposed in the literature [3]. The resulting models show an improvement in simulating pressure wave propagation (e.g., [4][5][6][7]); other improvements are obtained with 2D models [8]. The results of most of the models have been compared to experimental data and satisfactory comparison was achieved even if with different assumptions.…”

Section: Introductionmentioning

confidence: 99%

New Dimensionless Number for the Transition from Viscous to Turbulent Flow

Nucci

Celli

Pasquali

et al. 2022

Fluids

View full text Add to dashboard Cite

Within the framework of Classical Continuum Thermomechanics, we consider an unsteady isothermal flow of a simple isotropic linear viscous fluid in the liquid state to investigate the transient flow conditions. Despite the attention paid to this problem by several research works, it seems that the understanding of turbulence in these flow conditions is controversial. We propose a dimensionless procedure that highlights some aspects related to the transition from viscous to turbulent flow which occurs when a finite amplitude pressure wave travels through the fluid. This kind of transition is demonstrated to be described by a (first) dimensionless number, which involves the bulk viscosity. Furthermore, in the turbulent flow regime, we show the role played by a (second) dimensionless number, which involves the turbulent bulk viscosity, in entropy production. Within the frame of the 1D model, we test the performance of the dimensionless procedure using experimental data on the pressure waves propagation in a long pipe (water hammer phenomenon). The obtained numerical results show good agreement with the experimental data. The results’ inspection confirms the predominant role of the turbulent bulk viscosity on energy dissipation processes.

show abstract

Section: Introductionmentioning

confidence: 99%

New Dimensionless Number for the Transition from Viscous to Turbulent Flow

Nucci

Celli

Pasquali

et al. 2022

Fluids

View full text Add to dashboard Cite

show abstract

Study on Advanced Water Level Simulation Method for Inland Waterway Transport Based on the Extended Manning Formula

Zhou

et al. 2023

Lecture Notes in Civil Engineering

View full text Add to dashboard Cite

The water level is a critical hydraulic parameter for inland ship safe navigation, as well as an important variable in inland waterway transport minoring and assistant systems. As a basic and traditional method, the one-dimensional (1D) hydrodynamic model is adapted to simulate river sections/waterway segments to obtain water levels numerically. However, the friction factor, i.e., Manning’s coefficient n, is a sensitive parameter for the traditional 1D hydrodynamic model. Its calibration or identification is not only very time-consuming but also unpractical. Due to its sensitivity to the simulation results, usually, one identified parameter cannot be adopted into other flow scenarios. It has been concluded that the unfitness of the traditional empirical quasi-steady friction formulae leads to these consequences/phenomena. Besides finding advanced parameter calibration algorithms and updating friction parameters dynamically, employing a true unsteady friction formula to replace the quasi-steady friction formula is a thorough solution to the problem. In this study, we introduced a newly proposed 1D unsteady friction formula to the momentum equation of the Saint-Venant Equations, thus a modified 1D hydrodynamic model was developed. To validate its capability in simulating water levels, the modified model was adopted into the Xia-la-xian – La-he-lian section of Daying River; and compared with the traditional model with the Manning formula. Results showed that the modified hydrodynamic model performs better in both water level and cross-sectional average velocity simulation. The research results can be used to support the construction of intelligent water level warning systems, intelligent shipping, and digital waterway transportation platforms.

show abstract

A weighting function model for unsteady open channel friction

Cited by 2 publications

References 20 publications

New Dimensionless Number for the Transition from Viscous to Turbulent Flow

New Dimensionless Number for the Transition from Viscous to Turbulent Flow

Study on Advanced Water Level Simulation Method for Inland Waterway Transport Based on the Extended Manning Formula

Contact Info

Product

Resources

About