Question

The following data will be used :

A rectangular channel measuring 2m in width on a horizontal slope conveys 3 m3 /s. Assume a frictionless channel.

1) A sub-critical flow depth (y) of 3.0m is observed for the given flow conditions above. Determine the alternate depth for the same specific energy. Determine the critical flow depth.

2) Assume for this question only that the flow depth that is occurring is the super critical flow depth for the specific energy determined in Question 1. Determine the conjugate/sequent depth and determine the amount of energy loss in a hydraulic jump.

Answer 1

PAGE Advanced fluid Mechanical 1.) width of channel = B = 2 m Dischaxge >= 3 m/s sub-critical flow depth of y=3m Sol- Part-B = flow depth is occurring at super-critical flow depth for the specific Energy - 423m AS 92-91 + J (y2 + 2q² Tu yg 42 2 - yot + 20² B24,9 2 c-142-3 + Jet + 2 (3) 2 2 (252 (35(9.81) Y2 = I lost 1.55 14 = oios m sequent Depth > Conjugate Depth =) y = 4, +42 Y = 3to.os 4= 3.05 m ) Conjugate Death - Amount of Energy loss in a Hydraulic Jump (DE) = 642 441) 44,42 DE = (3-0.05) 4 (3) 2005) : AE = 42.79 m) Amount of Energy loss in a Hydraulic Jump 3

DATE PACE Part-A Alternate depth = f for same specific Energy sub-critical flow) El-Ez 4t 92 Y + 0² 29 A? 29 A2² I yet Q² Y + ² 29 B,24,2 29824² 3t 2 42 t 219.81)(2) ² (312 2(9.81) (2) ² 4² 2.3t 0.0127 = + 0.1147 2 2 3.0 127 = 42 talla 4? 3.012742 to 1147 i 43 -3.01274 to.4 to 114720 Y2=3m - Alternate Depth for the same specific Energy Critical flow depth & Yc= / 92 12 9 Yc 02 / B²9 4 c = 32 2²(9.81) Yc= 0.612 m. c) Critical flow depth