Gradually varied theory, Eq. (10.49), neglects the effect of width changes, db/dx
Chapter 10, Problem p10.115(choose chapter or problem)
Gradually varied theory, Eq. (10.49), neglects the effect of width changes, db/dx, assuming that they are small. But they are not small for a short, sharp contraction such as the venturi fl ume in Fig. P10.113. Show that, for a rectangular section with b 5 b(x), Eq. (10.49) should be modifi ed as follows: dy dx < S0 2 S 1 3V 2 /(gb)4(db/dx) 1 2 Fr2 Investigate a criterion for reducing this relation to Eq. (10.49)
Unfortunately, we don't have that question answered yet. But you can get it answered in just 5 hours by Logging in or Becoming a subscriber.
Becoming a subscriber
Or look for another answer