A modification to the Wallingford rational regime theory

Eric Valentine, M Haidera

    Research output: Contribution to journalArticleResearchpeer-review

    Abstract

    The rational regime formulation, which was used by White, Bettess and Paris to predict the stable geometry of wide, trapezoidal alluvial channels and in producing the Wallingford Tables for the Design of Stable Alluvial Channels (Hydraulics Research, Wallingford, 1981), is reviewed. This approach (the Wallingford rational regime theory) is known to provide useful results for moderate-scale natural channels but deviates more widely from observed behaviour for laboratory channels and very large rivers. To explore possible reasons for this, wide and narrow trapezoidal channels have been examined in terms of wetted perimeter, hydraulic radius and side slope, and have been compared with equal-area rectangular channels. The effect of the hydraulic radius, via the threshold of motion, on the sediment transport prediction was studied. It is shown that the hydraulic radius associated with selection of side slope has a significant effect on the sediment concentration prediction. The threshold of motion is also an issue. The original method was modified by approximating the channel cross-section as an equivalent area trapezoidal section. Based on the results, an adjustment to the method in terms of hydraulic radius and threshold of motion is proposed. Laboratory flume and field data are used to examine the improved predictions of the modified method.
    Original languageEnglish
    Pages (from-to)71-80
    Number of pages10
    JournalWater Management
    Volume158
    Issue number2
    Publication statusPublished - 2005

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    hydraulics
    prediction
    channel hydraulics
    sediment transport
    cross section
    geometry
    river
    sediment
    method
    effect
    laboratory

    Cite this

    Valentine, E., & Haidera, M. (2005). A modification to the Wallingford rational regime theory. Water Management, 158(2), 71-80.
    Valentine, Eric ; Haidera, M. / A modification to the Wallingford rational regime theory. In: Water Management. 2005 ; Vol. 158, No. 2. pp. 71-80.
    @article{0561c1135f2c458ea46ba9f45fe90404,
    title = "A modification to the Wallingford rational regime theory",
    abstract = "The rational regime formulation, which was used by White, Bettess and Paris to predict the stable geometry of wide, trapezoidal alluvial channels and in producing the Wallingford Tables for the Design of Stable Alluvial Channels (Hydraulics Research, Wallingford, 1981), is reviewed. This approach (the Wallingford rational regime theory) is known to provide useful results for moderate-scale natural channels but deviates more widely from observed behaviour for laboratory channels and very large rivers. To explore possible reasons for this, wide and narrow trapezoidal channels have been examined in terms of wetted perimeter, hydraulic radius and side slope, and have been compared with equal-area rectangular channels. The effect of the hydraulic radius, via the threshold of motion, on the sediment transport prediction was studied. It is shown that the hydraulic radius associated with selection of side slope has a significant effect on the sediment concentration prediction. The threshold of motion is also an issue. The original method was modified by approximating the channel cross-section as an equivalent area trapezoidal section. Based on the results, an adjustment to the method in terms of hydraulic radius and threshold of motion is proposed. Laboratory flume and field data are used to examine the improved predictions of the modified method.",
    keywords = "Channel flow, Hydraulics, Rivers, Sediments, Alluvial channels, Hydraulic radius, Moderate-scale natural channels, Rational regime formulation, Flow of water, channel flow, hydrodynamics, river engineering, channel hydraulics",
    author = "Eric Valentine and M Haidera",
    year = "2005",
    language = "English",
    volume = "158",
    pages = "71--80",
    journal = "Water Management",
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    Valentine, E & Haidera, M 2005, 'A modification to the Wallingford rational regime theory', Water Management, vol. 158, no. 2, pp. 71-80.

    A modification to the Wallingford rational regime theory. / Valentine, Eric; Haidera, M.

    In: Water Management, Vol. 158, No. 2, 2005, p. 71-80.

    Research output: Contribution to journalArticleResearchpeer-review

    TY - JOUR

    T1 - A modification to the Wallingford rational regime theory

    AU - Valentine, Eric

    AU - Haidera, M

    PY - 2005

    Y1 - 2005

    N2 - The rational regime formulation, which was used by White, Bettess and Paris to predict the stable geometry of wide, trapezoidal alluvial channels and in producing the Wallingford Tables for the Design of Stable Alluvial Channels (Hydraulics Research, Wallingford, 1981), is reviewed. This approach (the Wallingford rational regime theory) is known to provide useful results for moderate-scale natural channels but deviates more widely from observed behaviour for laboratory channels and very large rivers. To explore possible reasons for this, wide and narrow trapezoidal channels have been examined in terms of wetted perimeter, hydraulic radius and side slope, and have been compared with equal-area rectangular channels. The effect of the hydraulic radius, via the threshold of motion, on the sediment transport prediction was studied. It is shown that the hydraulic radius associated with selection of side slope has a significant effect on the sediment concentration prediction. The threshold of motion is also an issue. The original method was modified by approximating the channel cross-section as an equivalent area trapezoidal section. Based on the results, an adjustment to the method in terms of hydraulic radius and threshold of motion is proposed. Laboratory flume and field data are used to examine the improved predictions of the modified method.

    AB - The rational regime formulation, which was used by White, Bettess and Paris to predict the stable geometry of wide, trapezoidal alluvial channels and in producing the Wallingford Tables for the Design of Stable Alluvial Channels (Hydraulics Research, Wallingford, 1981), is reviewed. This approach (the Wallingford rational regime theory) is known to provide useful results for moderate-scale natural channels but deviates more widely from observed behaviour for laboratory channels and very large rivers. To explore possible reasons for this, wide and narrow trapezoidal channels have been examined in terms of wetted perimeter, hydraulic radius and side slope, and have been compared with equal-area rectangular channels. The effect of the hydraulic radius, via the threshold of motion, on the sediment transport prediction was studied. It is shown that the hydraulic radius associated with selection of side slope has a significant effect on the sediment concentration prediction. The threshold of motion is also an issue. The original method was modified by approximating the channel cross-section as an equivalent area trapezoidal section. Based on the results, an adjustment to the method in terms of hydraulic radius and threshold of motion is proposed. Laboratory flume and field data are used to examine the improved predictions of the modified method.

    KW - Channel flow

    KW - Hydraulics

    KW - Rivers

    KW - Sediments

    KW - Alluvial channels

    KW - Hydraulic radius

    KW - Moderate-scale natural channels

    KW - Rational regime formulation

    KW - Flow of water

    KW - channel flow

    KW - hydrodynamics

    KW - river engineering

    KW - channel hydraulics

    M3 - Article

    VL - 158

    SP - 71

    EP - 80

    JO - Water Management

    JF - Water Management

    SN - 1741-7589

    IS - 2

    ER -