Scenario
Your company is just about to start constructing a water delivery system to the reservoirs serving a new town. As a recent graduate the company need you to examine some of the problems associated with the hydraulic aspects of this contract
LO 1 Be able to solve engineering hydrostatic problems LO 1.1 pressure measuring devices
Task 1.1 a The density of sea water is 1029kN/m3, what would the pressure difference between the bottom of a freshwater lake of depth 30m and 30m below the surface of the sea?
b) What equipment would be used to measure such pressures?
LO 1.2 Hydrostatic forces
Task 1.2 (a) What is the total force acting on a dam which is 120m long holding back (fresh) water at a depth of 42m?
(b) If the dam were capable of withstanding a force of 0.5GN at
what height above the bottom of the reservoir would the spill way have to be set?
LO2 Be able to solve engineering flow problems
2.1 carry out calculations for pipeline flow problems
Task 2.1 The difference between Laminar or Placid flow on one hand and turbulent flow on the other is determined by one of two numbers either the Reynold's number or the Froude number.
Explain the difference between the two and at what value or range of values does the transition to turbulent flow occur
L O 2.2 carry out calculations for open channel flow problems
Task 2.2 a) Use Darcey Weisbach equation to calculate the friction factor given that the head loss along a new 12km long straight pipe line is 20metre when the delivery is 30m3s-1 and the internal diameter of the pipe is 1m.
Assume density of water = 1000kgm-3
b) What would the head loss be some years later as the inside surface of the pipe line was worn causing the friction factor to increase by 40%? Assume that the velocity remains the same.
LO2.3 Analytical principles:
Task 2.3 a) Show how to make use of the Bernoulli Equation to measure the rate at which water is flowing in a horizontal pipe of internal diameter 100mm, show what measurements you would make and what additional modification you would need.
b) If the diameter of the pipe were to open out from 80mm to 150mm, what would happen to the flow velocity?
c) If water is flowing at a rate of 3ms-1 coming out of the end of the (80mm diameter) pipe and hits the wall of a reservoir. What force does the water apply to the wall ? What would happen to this force if the diameter of the exit pipe were to be increased by a factor of 2?
LO 2.4 Closed conduit flow:
Task 2.4 A spillway is needed for a dam. The spillway exit from the dam is 30m above the base of the dam and the bottom of the spillway is intended to be on the same height as the base of the dam but some 1000m away. The channel is 5m wide. The maximum allowable depth is 4m and the maximum expected flow is 30m3s-1
a) Calculate the slope of the channel b) Calculate the minimum velocity at maximum flow c) Thus calculate the Manning n value of the channel
d) If the n value could be adjusted to 0.011 the value for smooth concrete what would the velocity of flow be at maximum
e) What would the depth of flow be at maximum flow.
LO 2.5 Uniform open channel flow:
Task 2.5
a) What is the width needed to keep the depth to maximum of 3m with following conditions. Delivery is 12m3s-1 given the slope of the channel is 0.011 and the value of n is 0.012.
b) If the channel over long use became rougher so that the Manning n value increased to 0.019 but it was still required that the depth must not exceed 3m, how would this change the maximum delivery of the channel
LO 2.6 Flow measurement in open channels:
Task 2.6 Explain why it is easier to measure water flow (in m3/s) in a pipe than in an open channel. Give one example of how flow is measured in a pipe and one how it is measured in an open channel.
LO3: Be able to match pumps to the demands of a specific system
LO 3.1 Pump matching: energy and hydraulic gradients in pump- pipeline systems; pump performance and characteristic curves; pump selection to operate in a given system; pumps in series and parallel
Task 3.1 i) The table given below gives the characteristics of a centrifugal pump running at a steady speed:
Fresh water is pumped to a service reservoir through a 0.3m diameter pipe 10km long. The static head is30m. Determine the discharge through the pipe and the power requirement of the pump. (This will need you to plot the pump - characteristic, system characteristic and efficiency curves against flow rate (Q).)
You must also find the operating point Assume the friction factor f = 0.0018 and take minor losses at twenty times the velocity head.
ii) In the above situation a second reservoir at a height of 30m above the original one needs to be supplied. Using the same type pump and a new 0.5m pipeline show what output you would get from a single pump and how you could arrange a second pump to maximize the output.
LO 3.2 Specific systems: hydrodynamic machines; classification of pumps and turbines (radial, axial, reaction)
Task 3.2
i) Outline the main characteristics of centrifugal and positive displacement pumps.
ii) State the three main types of turbine and state the conditions in which ONE of these are used for energy generation.
LO4: Be able to undertake hydraulic experimental procedures
Task 4 You have participated in a number of different experiments in the hydraulics lab. Undertake brief reports as outlined below on four which much include
a)Measurement of flow in open channels using weirs and b) the demonstration of Bernoulli's Principle and c) one further experiment of your choosing. In each experimental report provide the following:
i) Brief clear statement of the experimental procedures emphasising any changes from the procedures given in the handbook
ii) A clear table of results iii) Clear calculations of the data from the results
iv) Discussion of accuracy of the experimental results and any suggestions re changes in procedure
v) Application of this to real engineering problems
Writing Guidelines
- Your evidence for assessment must be handed in with a signed learner declaration.
- You must hand in group work for assessment for all tasks.
- Throughout the assignment you should underpin your responses with appropriate theories.
- Ensure that all required Learning Outcomes and Assessment Criteria are covered in the assignment.
- Ensure to provide citations, referencing and bibliography under Harvard Referencing System for your submission and it must fully acknowledge sources such as books and journals, websites etc.
- Including quotations, but exclusive of the reference list, bibliography and appendices, the assignment might be written in 2000 - 3000 words in length.
- Submit a word-processed report and use Times New Roman/Arial font and font size 12. Use 1.5 or 2.0 line spacing.
- All assignments will be subject to Plagiarism checks. Ensure your assignment does not contain the Collusion and Plagiarism of any type, which is illegal and attract disciplinary action against the learner.
- Ensure to follow the Standard Report Format for report preparation: (This an indicative structure)
- Introduction
- Contents page (with a detailed numbering system)
- Tasks (use headings, sub-headings)
- Findings/Discussion
- Recommendations
- Conclusion/Summary (summarizing the whole scenario justifying methods used)
- References
- Bibliography
Attachment:- Assignment.rar