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Free-surface stability criterion as affected by velocity distribution

Chen Cheng-Lung
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Abstract

This paper examines how the velocity distribution of flow in open channels affects the kinematic and dynamic wave velocities, from which the various forms of the Vedernikov number V can be formulated. When V >1, disturbances created in open-channel flow will amplify in the form of roll waves; when V <1, some (though not all) disturbances will attenuate. A study of the Vedernikov stability criterion reveals that it can be readily deduced within the framework of the kinematic and dynamic wave theories by comparing the kinematic wave velocity to the corresponding dynamic wave velocity. -from Author

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Chen Cheng-Lung. 1995. Free-surface stability criterion as affected by velocity distribution. https://doi.org/10.1061/(asce)0733-9429(1995)121%3A10(736)

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