Direct Derivation of Streamwise Velocity from RANS Equation in an Unsteady Nonuniform Open-Channel Flow
Publication: Journal of Engineering Mechanics
Volume 148, Issue 12
Abstract
This study investigates the vertical profile of streamwise (longitudinal) velocity in an unsteady and nonuniform open-channel turbulent flow. In contrast to the previous works, a direct derivation for velocity distribution starting from Reynolds-averaged Navier-Stokes (RANS) equation has been shown. Due to unavailability of several expressions for unsteady flow to solve the governing equation, a few assumptions have been made. The proposed model contains the effect of secondary current, which is generally present in all types of open-channel flow. The resulting partial differential equation has been solved numerically. Validation has been done by comparing the model with available experimental data and an existing analytical model.
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References
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Information & Authors
Information
Published In
Journal of Engineering Mechanics
Volume 148 • Issue 12 • December 2022
Copyright
© 2022 American Society of Civil Engineers.
History
Received: Jan 24, 2022
Accepted: Aug 2, 2022
Published online: Sep 29, 2022
Published in print: Dec 1, 2022
Discussion open until: Feb 28, 2023
ASCE Technical Topics:
- Channel flow
- Channels (waterway)
- Engineering fundamentals
- Equations (by type)
- Flow (fluid dynamics)
- Fluid dynamics
- Fluid mechanics
- Fluid velocity
- Hydraulic engineering
- Hydraulic structures
- Hydrologic engineering
- Mathematics
- Navier-Stokes equations
- Nonuniform flow
- Open channel flow
- Open channels
- Unsteady flow
- Velocity distribution
- Velocity profile
- Water and water resources
- Waterways
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Cited by
- Rafik Absi, Suspended Sediments in Environmental Flows: Interpretation of Concentration Profiles Shapes, Hydrology, 10.3390/hydrology10010005, 10, 1, (5), (2022).