PUMP AND PIPELINE HYDRAULICS CIV2300a

PUMP AND PIPELINE HYDRAULICS
CIV2300a
Semester 1 Coursework Brief
Dr Richard Collins
r.p.collins@shef.ac.uk
Mappin Building F119
2020
1 Introduction
This coursework is based around the design of a new gravity fed bulk water transfer pipeline that is due to be
constructed between Grantham and Lincoln in Lincolnshire. The pipeline is required to provide a new source
of water to the growing city of Lincoln from the hills to the south.
This coursework will initially allow you to build up and test a series of small scale hydraulic models of the
pipeline. You will then asked to design the pipeline, following the predetermined route as arranged with the
local council, see Figure 1. The route travels from the upstream supply reservoir to the south to the local water
treatment reservoir just to the north west of Lincoln. The pipeline route is 84 km long, and the elevation of
the ground drops by about 125 m over the distance travelled. Finally you are asked to consider the impact of
ensuring a water supply to the RAF base at RAF Waddington.
This coursework is designed to let you explore flow in pipes in a little more detail than we have time for in
tutorial questions and get used to managing a large amount of calculations. The initial series of tasks you will
have to undertake of increasing complexity that will test your knowledge of networks of pipe flows, and provide
you with the tools to analyse the design of the new pipeline.
You may need to do some additional reading around the subject of water supply systems and pipe networks to
address all the points in the coursework.
1
University of Sheffield
Department of Civil and Structural Engineering
Pump and Pipeline Hydraulics
CIV2300a
Inlet Reservoir
Outlet Reservoir
RAF Waddington
Figure 1: Pre-agreed route of the pipeline from Grantham to Lincoln and route profile
2
University of Sheffield
Department of Civil and Structural Engineering
Pump and Pipeline Hydraulics
CIV2300a
2 Coursework Problem
The first task is to build a series of conceptual models which address some common pipelines and networks. For
this section of the coursework you will each have individual input data to use for your calculations.
2.1 Part 1: Flow between two reservoirs
For the first part of the work you need to assess the flow between two reservoirs assuming there are no customers
or other connections drawing water from along the pipeline. The reservoirs are connected by two pipes with
different properties, connected in series. This can be considered to be a simple representation of the final
pipeline. Figure 2
Figure 2: Two reservoirs connected by two pipes (P1 & P2) in series
You need to calculate
ˆ the flow rate between the two reservoirs
ˆ the total head at the junction between the two pipes
2.2 Part 2: Flow between two reservoirs, with a demand
To further assess the capacity of the pipeline, you need to ensure that the pipeline is capable of feeding additional
of customers. In this simple stage you should assume that all the customer demands are lumped together as a
single demand, QD, at the junction between the two pipes. This simple model might represent the potential
for supply of water to RAF Waddington.
Figure 3: Two reservoirs connected by two pipes (P1 & P2) in series with a demand
(QD) at the junction between pipes
You need to calculate
ˆ the flow rate in each of the two pipes
ˆ the total head at the junction between the two pipes
3
University of Sheffield
Department of Civil and Structural Engineering
Pump and Pipeline Hydraulics
CIV2300a
Input Data for the first 2 parts
To help ensure that the coursework is individually undertaken each student has their own data set for the first
2 calculation problems. You will find the data on the module Blackboard Coursework Brief tab, please let
me know at the first opportunity if you cannot find your data set or you think there is an issue with the data.
You will each receive an individual set of pipe properties, reservoir heads and demands for this piece of coursework. You will find the this data in the file Civ2300_CourseWork_Variables_20.xls. This file is a table that
lists all the required parameters against student ID numbers; first find your student ID number and read across
for your individual properties. ‘Length 1 (m)’ corresponds to the length of the pipe P1 in the figures below,
‘Diameter 2 (m)’ to the diameter of pipe P2 etc. ‘QD (l/s)’ is the demand flow in Figure3.
The final two columns ‘HA (m)’ and ‘HB (m)’ give the Total Head at the first and second reservoir surfaces
respectively, where the question only relates to a single reservoir use the values for ‘HA (m)’.
For the first two parts you can assume all pipes have an absolute roughness of 0.01 mm, and that
the elevation of the pipe is constant, you do not need to include minor losses in your calculations
2.3 Part 3a: Grantham to Lincoln Pipeline design
For this part of the work, rather than calculate a flow rate for given pipe properties you will have to make some
decisions on pipe properties and produce a design for the Grantham – Lincoln pipeline.
Design Brief
The local water company requires a pipeline design that will allow the maximum continuous flowrate between
the upstream reservoir at Grantham and downstream reservoir at Lincoln WTW, safety and integrity of the
design are critical. This pipeline is designated as a piece of critical infrastructure so cost considerations are
not the primary concern and do not need to be assessed however preference would be given to designs that
demonstrate minimal environmental impacts.
Whilst the route and elevation is fixed (Figure 1) you are required to make design choices about the types and
diameters of pipe you wish to use for the route. Tables of pipe properties, and trenching conditions, can be
found in Appendices B, other properties you should be able to determine from materials given to you during
the course. Additional pipe furniture; valves, expansions, contractions etc. can be used if required.
You can assume that the water surface at the inlet reservoir is 4 m above the ground elevation at the start of
the pipeline, and the water surface at the outlet reservoir is 2 m above the ground elevation at the end of the
pipeline.
Your final solution will need to be supported by design calculations that demonstrate the viability of your
solution and how it meets the brief.
2.4 Part 3b: Grantham to Lincoln Pipeline design with flow take off
The pipeline passes next to RAF Waddington, an active RAF base. To support and ensure the resilience of
the RAF base the water company has been approached by the RAF to assess the potential for an additional
water supply to the base. For this part of the coursework briefly detail the impact of supplying the base with
a constant 10 l/s water supply would have on your pipeline design.
4
University of Sheffield
Department of Civil and Structural Engineering
Pump and Pipeline Hydraulics
CIV2300a
3 Assessment and Submission
The coursework needs to be submitted in two parts, the numerical solutions to the problems need to be submitted
via a Google Form https://goo.gl/forms/XHoZQfwPnEAWJnDY2. All answers should be given to a suitable
precision.
Part 3a and b needs to be submitted as a short (no more than 4 page, including all figures,
appendices and references) outline of your design and a justification of decisions made. The
coursework report needs to be submitted into Turnitin using the Assessments/CIV2300 Report
(Autumn) section
Please ensure that any numerical calculations presented as part of the written report, are well laid out and
clearly presented.
You will receive marks based on the numerical accuracy of the answers to the first 2 parts of the coursework
(25%), and your design and the justification for your design choice for part 3a and b (75%). In addition the
first three parts are not weighted equally:
ˆ Part 1: 10%
ˆ Part 2: 15%
The submission date for the coursework is 9 am on Wednesday 18th of November, Week 8. I remind
you that coursework can be submitted before the deadline.
4 Solution Techniques
I don’t want to proscribe how you should undertake this coursework, the calculations should be able to be
completed with hand calculations, using a spreadsheet or using a more general programming solution like
MATLAB. However this assessment has been designed such that the early sections should be helpful for the
later sections. Therefore if you create a suitable script for the first part it should be reusable in later parts
etc., I hope that this should steer you towards something like MATLAB. Also you will have to undertake many
iterations to get a converged solution, so it will be an awful lot of hand calculations, so that may also steer you
towards a computational approach.
4.1 Hints on iterative solutions in MATLAB
This section is designed to help you undertake the problem using some basic MATLAB scripts.
The basic way of iterating through a calculation in MATLAB is to employ a loop. There are a number of
different types of loop but the easiest to setup is the for loop. An example of this in pseudocode is given in
Listing 1
Listing 1: Pseudo-code to undertake an iterative calculation
1 P = 2 % Some parameter
2 3

4 5 that calculates A using A and the
6 7 5
University of Sheffield
Department of Civil and Structural Engineering
Pump and Pipeline Hydraulics
CIV2300a
This is a very simple approach but can be usefully employed to solve problems in pipeline flows. Listing 2 shows
a for loop being used to calculate the flow rate along a pipe if the headloss is known, and it is already known
that the flow will be laminar. If you copy this code and run it in a MATLAB script you will see that it will
always run for 20 iterations, and the Reynolds number converges to approximately 381.
Listing 2: Pseudo-code to calculate the flow rate for known headloss for laminar flows
1 % The physical properties
2 rho = 998
3 mu = 1e -3
4 g = 9.81
5 6
% The system properties
7 d = 0.005
8 l = 500
9 hl = 5
10
11 % Initial guess of the Reynolds Number
12 Reynolds = 1e2
13
14 % Looping through 20 times
15 for i = 1:20
16 lambda = 64 / Reynolds ; % Calculating the laminar friction factor
17 V = sqrt (2 * g * d * hl / ( lambda * l)); % Calculating the velocity from
the Darcy Equation
18 Reynolds = rho * V * d / mu % Calculating the Reynolds Number associated
with the calculated velocity
19 end
20 % Check that the Reynlds number for the last few iterations hasn ‘t changed
21 %The final flow rate
22 Q = V * pi * d^2 / 4
This loop uses the previously calculated Reynolds number as the start point for the next step of the loop, which
is not always the most efficient method, however it should get you to a solution. The loop is also not intelligent
as it doesn’t know when to stop, the number of iterations is pre-determined before running. If you change the
system properties and the initial guess of Reynolds number you will be able to find examples which converge
after only one or two iterations (or maybe not at all). It is possible to programme more intelligent loops that
will stop when the solution is suitably converged (i.e. the difference between the current and previous result is
smaller than some preset value), this can be achieved via a while loop or conditions (if and else statements)inside
the for loop.
When programming if you can write down step by step what you want to achieve (either in words or equations)
you can programme it. All you then need is the exact suitable commands, and the best place for that is Google.
‘How do I … in Matlab’.
6
University of Sheffield
Department of Civil and Structural Engineering
Pump and Pipeline Hydraulics
CIV2300a
Appendices
A Route Profile
A digital version of the route profile, Figure 1, can be found from the excel file Profile.xlsx, which is in the
Coursework Brief folder in the module Blackboard Page.
B Pipeline Properties
B.1 Polyethylene Pipe
Embodied Carbon for PE pipes 2.52 (kg CO2 /kg)
7
University of Sheffield
Department of Civil and Structural Engineering
Pump and Pipeline Hydraulics
CIV2300a
Table 1: Polyethylene Pipe weights

Table 2: Polyethylene pipe ratings

8
University of Sheffield
Department of Civil and Structural Engineering
Pump and Pipeline Hydraulics
CIV2300a
B.2 Cast Iron Pipe
Table 3: Cast Iron Pipe weights and maximum allowable pressures

Embodied Carbon for Cast Iron pipes 1.45 (kg CO2 /kg)
B.3 Trench Properties
Table 4: Pipe trench sizes

Carbon Equivalent for pipe trench excavation and reinstatement 4.18 (kg CO2 / m3)
C Suggested Reading
ˆ Hydraulics in Civil and Environmental Engineering, Chadwick and Morfett
9
University of Sheffield
Department of Civil and Structural Engineering
Pump and Pipeline Hydraulics
CIV2300a
ˆ Drinking Water Distribution Systems: Assessing and Reducing Risks (2006) Chapter: 1 Introduction
available at: https://www.nap.edu/read/11728/chapter/3
ˆ Twort’s Water Supply, Ratnayaka, available as an electronic resource through StarPlus
10