Open-Channel Flow 2nd. Edition by M. Hanif Chaudhry | 9780387301747 | 0387301747

Fluid Mechanics

Open-Channel Flow

21 SOLVED PROBLEMS

1 SOLVED PROBLEMS

Question: 11.1

A 1-m wide rectangular channel is carrying a flow of 5 m³/s at a flow depth of 2 m. Determine the height of a surge wave and its velocity if the discharge is suddenly increased to 10 m³/s at the upstream end. Given: Q1 = 5 m³/s; Q2 = 10 m³/s; y1 = 2 m; B = 1 m. Determine: y2 = ? Vw = ? ...

Verified Answer:

The flow velocity at section 1,

V_{1} = Q_{...

Question: 14.1

A trapezoidal channel having a bottom width of 6.1 m and side slopes of 1.5H to 1 V is carrying a flow of 126 m³/s at a flow depth of 5.79 m. The bottom slope is 0.00008, Manning n = 0.013 and the channel length is 5 km. There is constant level reservoir at the upstream end of the channel. If a ...

Verified Answer:

A computer program was written based on these fini...

Question: 9.4

By using the regime approach, determine the cross section of an alluvial channel for a design flow of 8 m³/s. The sediment carried by water is 0.4 mm sand. Given: Q = 8 m³/s d = 0.4 mm Determine: Bo = ? y = ? ...

Verified Answer:

P = 4.75

\sqrt{8}

= 13.44 m

f...

Question: 9.3

Design a straight trapezoidal channel for a design discharge of 10 m³/s. The bottom slope is 0.00025 and the channel is excavated through fine gravel having particle size of 8 mm. Assume the particles are moderately rounded and the water carries fine sediment at low concentrations. Given: ...

Verified Answer:

For fine gravel, n = 0.024 and s = 1V:3H. Therefor...

Question: 9.2

Design a channel to carry a flow of 6.91 m³/s. The channel will be excavated through stiff clay at a channel bottom slope of 0.00318. Given: Q = 6.91 m³/s So = 0.00318 Channel material is clay. Determine: Bo = ? Flow depth = ? ...

Verified Answer:

For stiff clay, n = 0.025, suggested side slope, s...

Question: 9.1

Design a trapezoidal channel to carry a discharge of 10 m³/s. The channel will be excavated through rock by blasting. The topography in the area is such that a bottom slope of 1 in 4000 will be suitable. Given: Q = 10 m³/s Flow surface is blasted rock So = 0.00025 ...

Verified Answer:

For the blasted rock surface, n = 0.030 and the si...

Question: 6.2

A trapezoidal channel having a bottom slope of 0.001 is carrying a flow of 30 m³/s. The bottom width is 10.0 m and the side slopes are 2H to 1 V. At the downstream end, a control structure raises the water depth to 5.0 m. Determine the water-surface levels at 1, 2, and 4 km upstream of control ...

Verified Answer:

Let us call the location at the control structure ...

Question: 6.3

Figure 6-13 shows a channel network. The channel data are listed in Table 6-3. All channels have subcritical flow and trapezoidal cross sections having side slopes of 1.5 horizontal to 1 vertical. The flow depth at the downstream end (Node F) is 5 m for a flow of 250 m³/s. The form loss coefficient ...

Verified Answer:

The channels and nodes are numbered as shown in Fi...

Question: 6.1

A trapezoidal channel having a bottom slope of 0.001 is carrying a flow of 30 m³/s. The bottom width is 10.0 m and the side slopes are 2H to 1 V. A control structure is built at the downstream end which raises the water depth at the downstream end to 5.0 m. Compute the water surface profile. ...

Verified Answer:

The normal depth,

y_{n}

, for this c...

Question: 5.5

Sketch possible water-surface profiles in a long channel with a compound cross section and a reservoir at its upstream end, as shown in Fig. 5-14. The reservoir water surface is 1.2 m above the channel bottom at the channel entrance. ...

Verified Answer:

The method presented in the previous section to de...

Question: 2.3

A hydraulic jump is formed in a 5-m wide outlet at a short distance downstream of a control gate (Fig. 2-13). If the flow depths just downstream of the gate is 2 m and the outlet discharge is 150 m³/s, determine i. Flow depth downstream of the jump; ii. Thrust on the gate; and iii. Head losses in ...

Verified Answer:

The unit discharge in the outlet, q = 150/5 = 30 m...