Vertederos

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CHAPTER 7 - WEIRS 7. V-Notch Weirs of Any Angle The Kindsvater-Shen relationship can be used for fully contracted notches of any angle between 25 degrees and 100 degrees (Kulin andCompton, 1975). The equation which includes the angle as a variable is written as:

(7-3) where: Q = discharge over weir in ft3/s Ce = effective discharge coefficient h1 = head on the weir in ft h1e= h1 + kh = angle of V-notch The head correction factor, kh, is a function of (figure 7-6a). However, for fully contracted traditional 90-degree V-notch weirs, equation 7-6 and the rating tablediscussed later produce comparable accuracy.

Diseño de Vertederos Triangulares

Figure 7-6a -- Head correction factor, kh, for V-notches of any angle (courtesy of National Bureau of Standards, Kulin etal. [1975])..

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Figure 7-6b -- Effective coefficient, Ce, for fullycontracted Vnotches of any angle (courtesy of National Bureau of Standards, Kulin et al. [1975]).. For fully contracted V-notch weirs, the value of kh is related to as given on figure 76a, and valuesof Ce are read from figure 7-6b. Partially contracted 90-degree Vnotches only can be rated using figure 7-7 to obtain Ce values. The calibration relationships were developed with rectangular approachflow and head measurement sections for these weirs. For applications with other flow section shapes, the average width of the flow section for each h1 is used as B to determine coefficients.Diseño de Vertederos Triangulares

Figure 7-7 -- Effective coefficient, Ce, for partially contracted 90degree V-notches (courtesy of National Bureau of Standards, Kulin et al. [1975]).. Bos (1989) andInternational Organization for Standardization (1983) explain and define limits basic to the use of these figures. Precautions and restrictions concerning the use of V-notch weirs are as follows: (a)...