FACULTY OF ENGINEERING, BUILT ENVIRONMENT
AND INFORMATION TECHNOLOGY
DEPARTMENT:
MECHANICAL AND MECHATRONICS
ENGINEERING
PROGRAMME:
Bachelor of Engineering Technology (Mechanical
Engineering)
MODULE NAME:
HYDRODYNAMIC MACHINES 3
MODULE CODE:
MHM32A
NQF LEVEL:
CREDITS:
7
14
COMPILED BY:
Mr LR Masheane
DATE REVISED:
09/202
CONTENTS
PRACTICAL GUIDE
CONTENTS
1.
Module overview ........................................................................................... 3
1.1
Purpose Statement
3
1.2
Graduate Attributes to be assessed in this Module
3
1.3
Mark allocation
3
2.
Practical 1: Centrifugal Pump ...................................................................... 6
3.
Practical 2: Pelton Wheel ............................................................................. 8
4.
Laboratory and practicum rules:................................................................ 10
5.
Safety ........................................................................................................... 11
5.1
General Safety
11
5.1.1
What to do ................................................................11
5.1.2
What not to do ..........................................................11
5.1.3
Further points to consider .........................................11
6.
Practical report ............................................................................................ 12
7.
Practical/Assignment Submittal and Identification Sheet ........................ 13
2
1.
Module overview
1.1
Purpose Statement
Practical work is an essential part of work to be studied in the subject, Fluid
Science III. The student is expected to hand in a report upon completion of each
practical. This report must include background theory, equipment used during the
practical, procedure used during the practical, results, analysis, discussion and
conclusions. The document must be in the format and at the same standard of
work that you will submit to your employer.
This report must be handed in one week after completion of the practical for
evaluation. The total mark for all your practical’s and assignment is 35% of the
course mark. An average of 50% for the practical mark must be obtained for
admission to the main evaluation
NB: You can be refused entrance to the laboratory if:
o
o
1.2
You have not prepared for the practical.
You do not have a laboratory coat and laboratory notes.
Graduate Attributes to be assessed in this Module
No Graduate Attributes will be assessed in this module.
1.3
Mark allocation
REPORT
FORMAT AND
STYLE
WEIGHT
Aim
6%
Does not meet
expectations
1-2 marks
Aim of work unclear
(Incomplete)
1-2 marks
Apparatus
6%
Same sketch as study
guide
Meets expectations
Exceed expectations
3-4 marks
Clear
aim with
adequate overview
of scope of work
(Copied)
3-4 marks
5-6 marks
Clear aim,
thoroughly defines
scope of work,
thorough overview
(Own words)
5-6 marks
Adequate sketch or
image with
identification of
components. No
captions
Clear sketch with
all labels and
captions, required
descriptions
3
0-1 marks
Procedure
Theory
6%
8%
5%
TECHNICAL
CONTENTS
Tabulation of
experimental
results
Calculations
Graphs
Summary and
conclusions
12%
15%
20%
12%
4-6 marks
Adequate
steps/methodology
for the experiment
are provided
0 – 3marks
4-5 marks
Detailed
steps/methodology
for the experiment
are provided with
additional steps,
numbered
6-8 marks
Fails to cover
theoretical
explanations (some
formulas, not
applicable theory)
Adequately
addresses
theoretical
explanations (some
applicable theory
and all formulas)
1-3 mark
Demonstrates in
depth
research
and analysis (all
applicable theory
and formulas)
4-5 marks
Most sources are
appropriately cited
and a list of
references in the
IEEE style is
adequately
compiled.
All sources are
correctly and
thoroughly cited
Meets expectations
Exceed expectations
5-8 marks
Some experimental
data (some units)
provided,
6-11 marks
Examples of all
calculations with soe
incorrect values
9-12 marks
All experimental
data (with units)
provided
12-15 marks
Examples of all
calculations with
correct values and
answers
15-20 marks
Complete set of
graphs with correct xand y-axes/data
expressed on logical
presentations
8-12 marks
Same as study guide
0
Citation and
references
2-4 marks
Fails to correctly cite
and reference
sources
Does not meet
expectations
1-4 marks
Incomplete data set
1-5 marks
Incomplete
calculations
0-6 marks
Incomplete graphs
with wrong x-and yaxes
7-14 marks
Complete set of
graphs with some
wrong x-and yaxes/data
0 – 3 marks
4-7 marks
Fails to provide an
adequate summary
of the practical. Fails
to
provide conclusions
regarding the
experiment
An adequate
summary of the
practical is
presented.
Conclusions
regarding the
experiment are
A proper and
complete summary of
the practical is
provided. Well
thought through
conclusions regarding
the experiment are
provided.
4
adequately
discussed.
Structure and
neatness of
report
10%
0 – 4 marks
5 -7 marks
8 – 10 marks
Document is
formatted poorly,
paragraphs are
poorly organized,
sentences are poorly
written with
incorrect grammar,
punctuation,
spelling.
Accuracy of
experiment report
and calculations not
to standard
Document format is
generally consistent,
paragraphs are
usually well
organized, sentences
are generally well
written with a few
incorrect grammar,
punctuation,
spelling. Accuracy of
experiment report
and calculations up
to standard
Document format is
professional,
paragraphs are well
organized, and
sentences are well
written with no errors
in grammar,
punctuation, and
spelling. Accuracy
of experiment report
and calculations
exceptional
5
2. Practical 1: Centrifugal Pump
1.
AIM:
To investigate the operating characteristics (pressure head, input power, power
delivered and efficiency) against the discharge of the pump.
2.
APPARATUS:
Gilkes CH-75 Centrifugal pump
Spring
Mercury
Delivery valve
3.
THEORY:
Suction pressure
= p1
Delivery pressure
= p2
Flow rate
= Q
Total pressure head across pump = Ht = (p2 – p1)/w
w = specific weight of water
Torque (T )
= Brake load × brake arm
= Brake load × 0,179 Nm
Shaft power (Pin)
= 2πNT/60
Power delivered (Pout) = ρgHtQ
Efficiency of pump
= Power delivered
Input power
Q = 0,0967 x (H)0.5, where H is in mm HG. (Mercury manometer)
4.
METHOD:
4.1
Open the valve on the suction pipe and switch on the pump. Slowly open
the flow control valve on the delivery pipe. Adjust the pump speed to 1 800
r/min.
6
4.2
4.3
4.3.1
4.3.2
4.3.3
4.4
4.5
Open the flow control valve fully to obtain maximum flow.
Take the following readings:
the suction and delivery pressure
the brake load
the height (H) at the mercury manometer
Repeat the procedure for six different flow rates by means of further closing
of the flow control valve.
Repeat the procedure for a pump speed of 2 200 and 2 400 r/min.
5.
RESULTS:
Tabulate the results as follow:
Suction
pressure
Delivery
pressure
Brake
load
F
H
(mm H
G)
Torqu
e
T
Ht
Q
Shaft
powe
r
Power
delivere
d
Draw a graph of pressure head, shaft power, power delivered and efficiency
against the flow rate delivered for the three different pump speeds. A typical format
of the graph is shown in the figure below.
Take note that the figure below does not show the graphs of the pump use in this
experiment.
6.
CONCLUSION AND COMMENT:
Ht
Pin
ηo
ηo
Pi
Ht
Q
7
ηo
3. Practical 2: Pelton Wheel
1.
AIM:
To investigate the operating characteristics ( shaft power, input power, torque,
overall efficiency and flow rate) against bucket speed.
2.
APPARATUS:
Hydraulic bench
Pelton wheel apparatus
Stop watch
Tachometer
W
W
Spring
Pressure
3.
THEORY:
Output power (Pout) = Torque x angular velocity
= T ×ω
Brake drum radius (r) = 30 x 10-3m
T = (W1 − W2 )r
Input power (Pin) = ρgQH
H = Inlet head.
P
Overall efficiency (ηo) = uit
Pin
8
4.
METHOD:
4.1
4.7
Place the apparatus on top of the channel of the hydraulic bench. Make
sure that the pipe of the apparatus is coupled to the hydraulic bench.
Make sure that the pony brake is free from the drum and adjust each spring
balance reading to zero.
Switch on the pump and slowly open the flow control valve on the hydraulic
bench. Adjust the nozzle control on the apparatus until the turbine runs at
maximum speed.
Measure the speed of the wheel with the tachometer. Take the reading of
the inlet pressure head and determine the flow rate.
Adjust the pony brake so that the spring-balance reading W1 = 1 N. Measure
the speed, flow rate, the inlet pressure head and the readings on the springbalance.
Repeat the procedure for the values of W1 shown in the table supplied.
5.
RESULTS:
4.2
4.3
4.5
4.6
Tabulate the results as follow
R.P.M.
ω (rad/s)
W1 (N)
0
W2 (N)
W1 – W2 (N)
Drum radius x 10- 30
3m
Torque (T) (Nm)
Pm (W)
Volume (l)
Time (s)
Flow rate (m3/s)
Pressure (m)
Pw (W)
ηo (%)
1
2
3
4
5
6
30
30
30
30
30
30
Draw separate graphs of shaft power, input power, torque, overall efficiency and
flow rate against the bucket speed of the wheel.
6.
CONCLUSION AND COMMENT:
9
4.
Laboratory and practicum rules:
1.
The posted safety rules in the labs must be strictly observed.
2.
Non-attendance at practical sessions will result in automatic
disqualification for that practical point. Proof must be handed in within 3
(three) working days: in case of sickness, death in the family or any other cases
of emergency preventing the attendance of a practical session or the submission
of practical scripts.
3.
Students must prepare prior to the lab session by reading the laboratory manual
and completing all assigned pre-laboratory work for the experiments.
4.
Students should come to the laboratory on time!
5.
Laboratory overcoats and closed shoes must be worn during each session. No
open shoes are allowed in the laboratory.
6.
Do not commence with the practical session or handle any laboratory equipment
without supervision! Handle all apparatus with care to keep it in a perfect
condition.
7.
Students must actively participate in performing the experiments, and should also
take an active role in writing all extra information provided during laboratory work.
8.
Smoking and eating are prohibited inside the laboratory.
9.
No disturbances, individually or in a group will be tolerated. Do not rave, talk or
walk unnecessarily or fiddle with other apparatus inside the laboratory.
10.
Although practical sessions are done in a group, it is expected that every student
must hand in his own work (unless otherwise stated). All students participating
in duplication (copying someone else’s work) will be automatically
disqualified for that practical session. Dishonesty will be reported to the
Disciplinary Committee and could lead to permanent suspension from CUT.
11.
Late submittal penalties - Unless an extension has been sought and granted, late
assignments will be penalized when marking. The penalty rate will be -20%
if late but still handed in on same day. No assignments will be accepted after
the submission date! Therefore, it is in your interest to aim to complete the work
before the due date.
12.
A minimum Practical mark of 50% is required for Examination Approval
13.
The Practical mark makes up 35% of the semester course mark.
As stipulated by the Faculty’s rules and regulations - It is the student’s responsibility to adhere
to the above-mentioned Laboratory and Practicum rules.
10
5. Safety
5.1
General Safety
Close attention should be given to all aspects of safety throughout training, and the highest
possible standards insisted upon. There is a special need to emphasize the
fundamental safety rules of behaviour, dress and practice when students enters
a laboratory. Instructors have a particular responsibility to set a good example
and to check without delay any departure from safe working practices by
students. Individual responsibilities in respect of the safety of all persons in the
laboratory must be clearly understood by everyone. It is essential to develop safe
working habits.
5.1.1
•
•
•
•
•
•
5.1.2
•
•
•
•
•
•
•
5.1.3
•
•
•
•
•
•
•
•
What to do
Think before you act.
Ask if in any doubt.
Help to keep gangways clear.
Keep your bench and working area tidy.
Find out the position and type of fire appliances available.
Report all accidents to your supervisor
What not to do
Do not run.
Do not play practical jokes.
Do not touch any equipment or try out machines unless authorized to do so.
Do not leave rubbish lying about.
Do not walk under suspended loads.
Do not attempt to give first aid unless you are competent to do so.
Do not throw things.
Further points to consider
Wear your lab coats buttoned up.
Roll up your overall sleeves above the elbows or button up the cuffs.
Obey all safety rules and signs.
Report any accident, however slight.
Have all injuries properly treated, however minor.
Do not wear torn lab coats.
Do not wear rings or a watch when working.
Do not take chances.
IN CASE OF EMERGENCY:
1.
2.
3.
Report all abnormalities and accidents immediately to the lecturer or supervisor!
If required, evacuate the building in a quiet and calm manner.
The first aid kit and fire extinguisher may only be used by authorised people.
11
6. Practical report
The practical report must consist of the following:
Front Page: Use the “Assignment Submittal & Identification” form provided in this guide for
each report.
Inner pages of Report: All data, sketches, explanations and calculations. For reports
submitted through ethuto, calculations must be done by hand, scanned and
added to the final report. Graphs can be presented on graph paper. Note the
evaluation summary are items that should be in the report layout (by that order).
1.
Aim
Aim of the experiment/practical/assignment.
2.
Summary of Theory
Summary of the underlying theory, which you must present in your own words after searching
in the relevant literature (provide references).
3.
Sketch of the apparatus
Sketch and description of the apparatus, with reference to the most important measuring
points and/or measuring devices.
4.
Procedure
A short description, in your own words, of the experimental procedure.
5.
Experimental data & observations
Measured values and data in tabular form.
6.
Calculations (Graph if applicable)
Calculations must be shown clearly.
7.
Results
Results or final values must be presented again in tabular form (with experimental data) to
compare where possible (all data, experimental and calculated)
8.
Conclusion
Interpretation, discussion, remarks on some interesting observations, questions, etc.
12
7. Practical/Assignment Submittal and Identification Sheet
RESULT%
Student number(s):
Surname and initials:
Program:
Eng Tech (Mechanical Engineering)
odule name:
Hydrodynamic Machines III
Module code:
M
Graduate
None
Attribute (GA)
assessment:
1
H
2
3
M
4
3
5
6
2
7
A
8
9
10
Practical/Assignment
number:
Group number:
Due date:
2
0
Lecturer:
2
1
M
M
D
D
L Masheane
DECLARATION OF OWN WORK:
______________________________________________________________,
student
number______________________________________, hereby declare that the content of this
assignment/project is my own work, as defined and constituted in the Rules and Regulations of the
Central University of Technology, Free State (Please consult the Programme Guide of the Department).
Signed:
________________________________
Date:
________________________________
13