3 Hydrodynamics
203
Fig. 3.29 Boris Alexandrovich Bakhmeteff, 1880–1951, Russian hydraulician)
Fig. 3.30 Section specific energy at any cross section of open channel
In fact, the gravity potential energy at the bottom of the channel is
deducted from the specific energy of the section. Under a given discharge, the
trend of its variation with water depth is the theoretical basis for people to
analyze water surface profile. Under the given discharge, draw the relationship
curve between E s and h (called specific energy curve), as shown in Fig. 3.31.
It is found that the relationship between specific energy E s and water depth is
similar to the quadratic parabola. The straight line passing through the origin
at an angle of 45° between the upper end of the curve and the horizontal axis
is the asymptote, the lower end of the curve is the asymptote with the horizontal axis, and there is a minimum section (E smin ) specific energy particle
203
Fig. 3.29 Boris Alexandrovich Bakhmeteff, 1880–1951, Russian hydraulician)
Fig. 3.30 Section specific energy at any cross section of open channel
In fact, the gravity potential energy at the bottom of the channel is
deducted from the specific energy of the section. Under a given discharge, the
trend of its variation with water depth is the theoretical basis for people to
analyze water surface profile. Under the given discharge, draw the relationship
curve between E s and h (called specific energy curve), as shown in Fig. 3.31.
It is found that the relationship between specific energy E s and water depth is
similar to the quadratic parabola. The straight line passing through the origin
at an angle of 45° between the upper end of the curve and the horizontal axis
is the asymptote, the lower end of the curve is the asymptote with the horizontal axis, and there is a minimum section (E smin ) specific energy particle