EG5031 - Open Channel Hydraulic Design Assignment

Assignment Task

Part 

1.Rectangular Open Channel Design

For this portfolio (Part 1), you are required to design a rectangular open channel for maximum velocity to avoid scour (Vmax), the bed slope (S) and the Manning’s roughness coefficient (n).

The methodology to carry out this assessment is as follows:

1. You have been given a unique dataset (Vmax, S and n) to carry out this task. These datasets can be found in the EG5031 Moodle folder.

2. You may start your calculations using wide-channel approximation to keep the velocity below the permissible value for a selected channel width (b) to compute the steady discharge (Q).

3. You may repeat the calculations for best hydraulic section to compute channel width (b) and the steady discharge (Q), and make a comparison with values in Step 2.

4. State whether the flow in the channel is sub-critical or super-critical for a given slope and flow conditions. 5. Explain the suitability of the rectangular channel section against the other geometries such as trapezoidal, triangular etc. The Manning’s equation (Eq. 1) and the wide channel approximation (Eq. 2) are given below.

v = 1/n R ^2/3 s ^1/2   Eq. (1) 

R ≈ y    Eq. (2)

where,

• V = average velocity (m/s)

• n = Manning’s roughness coefficient (-)

• R = hydraulic radius (m)

• S = bed slope (-)

• y = normal depth (m)

2. Side Weir Design

For this portfolio (Part 2), you are required to design an off-take hydraulic structure (side weir) with 10% discharge (Q) of the flow you have calculated in Part 2. The methodology to carry out this assessment is as follows:

1. You may start your design by selecting a crest level for the side weir that is above the level of critical depth in the main channel. Then use the weir formula (Eq. 3) to find the required dimension b for the weir. You may assume a suitable value for Cd.

2. Explain in detail the problems arise in the vicinity of the weir off-take due to super-critical flow conditions and how these problems can be overcome. You may support your answer with sketches.

The weir formula (Eq. 3) is given below.

Q = 1.705C_d bH ^3/2 Eq. (3)

where,

• Q = flow discharge (m3 /s)

• Cd = discharge coefficient (-)

• b = width of the weir (m)

• H = total energy head above the weir crest (m)

Prepare a detailed report on Part 1 and Part 2 calculations. Your individual report is to be word processed, under the following key headings:

1) Introduction on open channel flow and structure design

2) Methodology (outlining method of equations/model and assumptions used).

3) Data analysis (application of Manning’s and weir formulae etc).

4) Discussion (Point 5 in Part 2 & Point 2 in Part 2).

5) Key conclusions (brief summary, perhaps a table of critical design values of Part 1 and Part2)

6) References (conforming with Harvard Style as per Cite them Right textbook).

Appendices (all bulk calculations should be included in the appendices).

This EG5031 - Engineering Assignment Help has been solved by our Engineering Experts at My Uni Papers. Our Assignment Writing Experts are efficient to provide a fresh solution to this question. We are serving more than 10000+ Students in Australia, UK & US by helping them to score HD in their academics. Our Experts are well trained to follow all marking rubrics & referencing style.