COURSE:
CHE 241 – FUNDAMENTALS OF FLUID MECHANICS
(3 Credits /Compulsory).
Course Duration: Three hours per week for 15 weeks
As taught in 2010/2011 session
LECTURERS:
1
OGUNLEYE,Oladipupo Olaosebikan
Ph.D., M.Sc, B.Tech., Reg. Engr.(COREN), MNSChE, MAIChE,MSIAM.
E-mail: ooogunleye@yahoo.com
Office Location: Rm 5, Ground Floor,Department of Chemical Engineering Building
Consultation Hours: 11.00-1.00pm Mondays and Wednesdays.
2
AJALA,Elijah Olawale
M.Sc ,B.Tech.,
E-mail: ajala.oe@unilorin.edu.ng
Office Location: – Rm 1, Ground Floor,Department of Chemical Engineering Building.
Consultation Hours: 11.00-1.00pm Mondays and Wednesdays.
Developer: Dr OGUNLEYE,Oladipupo Olaosebikan
.Course Content:
Properties of fluids, Fluids Statics, Basic conservation laws, friction effect and losses in laminar
and turbulent follows in ducts and pipes. Dimensional analysis and dynamic similitude,
principles of construction and operation of selected hydraulic machinery. Hydropower systems.
45h (T); C
Course Description:
The course is designed to introduce students in the Faculty of
Enginnering and Technology especially to lower level course in
fluid mechanics, which emphasizes the systematic application of
fundamental principles (e.g., macroscopic mass, energy, and
momentum balances and economics) to the analysis of a variety of
fluid problems of a practical nature. The scope of coverage
includes internal flows of Newtonian and non- Newtonian
incompressible fluids, adiabatic and isothermal compressible
flows .Applications include dimensional analysis and scale-up,
piping systems with fittings for Newtonian and non-Newtonian
fluids, compressible pipe flows, flow measurement, and control,
pumps, compressors.
1
Course Justification:
Nigeria being an oil-rich nation transports crude oil and its allied products through pipe
line where so many phenomena occur due to the nature of the fluid being transported, the
channel of transportation and the forces behind the transportation. Fluid mechanics gives clear
insight into the understanding of such systems as this. The economics of crude oil processing
will not be complete without an application of fluid mechanics to imrove pump efficiency in the
course of crude oil transportation thereby minimizing the cost and maximizing profit. This
principle is what many developed nations had applied to the management of their pipeline
networks whose integrity has been secured through Artificial Intelligent Systems.
Course Objectives:
The objectives of this course as an integral part for the award of B. Eng. are :

For the students to have an understanding of the fundamental principles underlying the
behavior of fluids in order to apply them in a systematic manner to solve practical
engineering problems.

To provide a ready reference and basic methods for the analysis of a variety of problems
encountered in the movement of fluids through pipes , pumps and all kinds of process
equipment.
Course Requirements:
This is a compulsory course for all students studying Engineering In view of this, students
are expected to participate in all the course activities and have minimum of 75% attendance
to be able to write the final examination.
Methods of grading:
No
1.
2.
3.
Item
Assignment/ Quiz / Monthly Test
Mid Semester Test
Examination
Total
Score %
10
20
70
100
Course Delivery Strategies:
The lecture will be delivered through face-to-face method, lecture guide (lecture note) will be
provided during lectures. Students will be encouraged and required to read around the topics.
The delivery strategies will also be supported by tutorial sessions.
2
LECTURES
Week 1 - 2:
General Introduction of Fluid Mechanics
Objective: The students should be able to explain the basic concept of fluid mechanics at the
end of these classes.
Description: The course outline will be introduced with emphasis on the objectives and delivery
strategies, definitions, the continuum concept , types of fluids, units of
measurements, properties of fluids, Viscosity, Compressibility of fluids, surface
tension and capillarity, vapour pressure.
Study Questions/Assignments:
1
2
3
4
5
Convert a force of 17 dynes to Newton, poundals and lbf.
A gas whose molecular weight is 28 is kept under a pressure of 200kN/m2 and a
temperature of 600C .Calculate the density of the gas.
The viscosity of an organic liquid is 15cP. Calculate the corresponding values on the
fps and SI system.
Two plates with area 10m2 are 2mm apart. The lower plate is fixed while the upper
plate is moved at a constant velocity of 1m/s by a force of 50N. Determine the
viscosity of the liquid between the plates.
A bubble of a liquid whose surface tension is 0.0289N/m has a radius of
1mm.Calculate the pressure within the bubble if the atmospheric pressure is
101kN/m2.
Reading List:
Darby4, R.(2001).Chemical Engineering Fluid Mechanics. Second Edition. Marcel
Dekker, Inc. New York. (pp. 1-13 ). ISBN 0-8247-0444-4
2 McCabe1,W. L., Smith,J.C. & Harriott, P. (1993).Unit Operations of Chemical
Engineering. Fifth Edition. McGraw Hill Co. Singapore.(pp.27-41 ).ISBN 0-07-112738-0
3 Ogboja2 ,O. (2005). Fluid Mechanics .UNESCO, Nairobi Kenya. (pp.1-21).ISBN 929158-000-7
4 Coulson4, J.M.,Richardson, J.F., Backhurst,J.R. & Harker, J.H. (2001). Chemical
Engineering Volume 1, Sixth Edition, Butterworth Heinmann Inc. Oxford.(pp. 27 -56).
ISBN 0 7506 4444 3
5 Douglas1,J.F. & Gasiorek, J. M. (1997). Fluid Mechanics. Third Edition,Longman Press,
Singapore.(pp. 1-29 ) .ISBN 81-219-1667-4
1
Week 3: Dimensional Analysis and Dynamic Similitude
Objective:
Students should be able to describe how independent variables are expressed in
terms of their dependent variables without experimentaion.
3
Description: Dimensional Analysis, Techniques of Dimensional Analysis, Interpretation of
Dimensionless Numbers and Dynamic Similitude.
Study Questions:
1
An ethylene storage tank in your plant explodes. The distance that the blast wave travels
from the blast site (R) depends upon the energy released in the blast (E), the density of the
air ( ρ ), and time (t). Use dimensional analysis to determine the dimensionless group(s) that
can be used to describe the relationship between the variables in the problem
2
Determine the number of the dimensionless parameters for the following functional
Δh
 f 6 V, D, ρ, μ, g  using step –by step method
relationship:
l
3 In general, the pressure drop p of a fluid in motion in a conduit depends on the length of the
pipe l ,its diameter D, the fluid velocity V, density , viscosity , surface tension , bulk
modulus k , gravitational acceleration g and pipe roughness e. Determine the  term for the
functional relationship
4 Water is used to simulate the flow characteristics of oil in an industrial pipeline. The diameter
of the test pipeline is 1/10th of that of the industrial pipeline. The viscosities of water and oil
are 3.0 x10-4 and 2.9 x 10-2 N.s/m2 while their densities are 1000 and 1720 kg/m3
respectively. If the water velocity in the test pipeline is 10m/s, what is the corresponding oil
velocity in the industrial pipeline?
5 The head on a spillway is 1.5m and the discharge is 100m3/min. What is the head on the scale
model of 1:80. Determine the model discharge.
Reading List:
1 Darby4, R.(2001) .Chemical Engineering Fluid Mechanics. Second Edition. Marcel
Dekker, Inc. New York. (pp. 15-52 ). ISBN 0-8247-0444-4
2 Ogboja2 ,O. (2005). Fluid Mechanics .UNESCO, Nairobi Kenya. (pp.193-218).ISBN 929158-000-7
3 Douglas1,J.F. & Gasiorek, J. M. (1997). Fluid Mechanics. Third Edition,Longman Press,
Singapore.(pp. 246-307 ) .ISBN 81-219-1667-4
Week 4:
Fluids Statics.
Objective: Student should be able to describe the forces which keep the body of fluid in static
equilibrium.
Description: Concept of stress and pressure, pressure transmission, pressure measurement,
Forces on submerged surfaces,Buoyancy and Static Forces on Solid Boundaries.
Student will also be assessed on the topics covered so far through a short Monthly
Quiz .
Study Questions:
1. If an egg can be crushed by pressure of 200kPa, at what depth will it burst in sean water
of specific gravity 1.1?
4
2. Predict the atmospheric pressure at a height of 1000m above sea level on a day when the
temperature is 300C.Assume that the air density at sea level is 1.15kg/m3 and take the gas
constant as 287J/kg.K. State other assumptions you make.
3. If the effort and load arm areas of a hydraulic jack are in the ratio 1:25, determine the
effort required to raise a load of one tonne mass.
4. A gate of a reservoir is hinged at a point and it is prevented from opening by the force in
the spring. The gate is 3m high and 1m wide. The level of water is 2m above th top of the
gate. Determine the force in the spring if the gate is just about to open.
5. The wall of a reservoir on which the slide gate is located is inclined at 300 to the
horizontal. The gate is hinged at its upper end and a massive weight is pushed against its
lower end to keep it closed. Determine the reaction of the weight and its direction if the
gate has a circular cross section of diameter 3m.
Reading List:
1 Darby4, R.(2001).Chemical Engineering Fluid Mechanics. Second Edition. Marcel
Dekker, Inc. New York. (pp. 85-104 ). ISBN 0-8247-0444-4
2 Ogboja2 ,O. (2005). Fluid Mechanics .UNESCO, Nairobi Kenya. (pp.1-21).ISBN 929158-000-7
3 Douglas1,J.F. & Gasiorek, J. M. (1997). Fluid Mechanics. Third Edition,Longman Press,
Singapore.(pp. 59-97 ) .ISBN 81-219-1667-4
Week 5 - 6:
Objective:
Basic Conservation Laws.
The students should be able to describe the mathematical laws guiding the
movment of mass and energy.
Description: The concept of system, Conservation of Mass, Conservation of Energy,
Irreversible Effects and Conservation of Momentum.
Study Questions:
1
2
3
4
water is flowing into top of a tank at a rate of 200gal/minute.The tank is 18in. in
diameter and has a 3in. diameter hole in the bottom,through which the water
flows out.If the inflow rate is adjusted to match the outflow rate,what will the
height of the water be in the tank if friction is negligible?
A vaccum pump operates at a constant volumetric flow rate of 10litre/min based
upon pump inlet conditions.How long will it take to pump down a 100L tank
containing air from 1 atm to 0.01atm, assuming that the temperature is constant?
Air is flowing at a constant mas flow rate into a tank that has a volume of
3ft3.The temperature of both the tank and the air is contant at 700F.If the pressure
in the tank is observed to increase at a rate of 5psi/min,what is the flow rate of air
into the tank?
Compressed gas is distributed from a works in cylinders which are filled to a
pressure P by connecting them to a large reservoir of gas which remains at a
steady pressure P and temperature T. If the small cylinders are initially at a
temperature T and pressure P0, what is the final temperature of the gas in the
cylinders if heat losses can be neglected and if the compression can be regarded as
reversible? Assume that the ideal gas laws are applicable.
5
5
Steam is flowing through an horizontal nozzle.At the inlet the velocity is 1000ft/s
and the entalphy is 1320Btu/lbm.At the outlet,the entalphy is 1200 Btu/lbm. If heat
is lost through the nozzle at a rate of 5 Btu/lbm of staem,what is the outlet
velocity?
Reading List:
1 Darby4, R.(2001).Chemical Engineering Fluid Mechanics. Second Edition. Marcel
Dekker, Inc. New York. (pp. 105-146 ). ISBN 0-8247-0444-4
2 McCabe1,W. L., Smith,J.C. & Harriott, P.(1993).Unit Operations of Chemical
Engineering. Fifth Edition. McGraw Hill Co. Singapore.(pp.64-82 ).ISBN 0-07-112738-0
3 Ogboja2 ,O. (2005). Fluid Mechanics .UNESCO, Nairobi Kenya. (pp.113-189).ISBN 929158-000-7
4 Douglas1,J.F. & Gasiorek, J. M. (1997). Fluid Mechanics. Third Edition,Longman Press,
Singapore.(pp. 126-245 ) .ISBN 81-219-1667-4
Week 7 - 8 :
Objective:
Pipe Flows
Students should have an understanding of various flow regimes and their effects
on flow velocities in pipes.
Description: Flow Regimes, Pressure Drop in Laminar Flow,Pressure Drop in Turbulent Flow,
Velocity Profiles in Turbulent Flow, Velocity Distribution, Pressure Losses in
Pipe Fittings and Pipeline Problems.Student will also be assessed on the topics
covered so far through a short Monthly Quiz.
Study Questions:
1 Classify the following flows as laminar or turbulent
a) Water at 200C flowing in a 0.30m diameter pipe at 1.1m/s.
b) Oil of specific gravity 1.1, viscosity 0.05kg/m.s at 200C flowing in a 0.15m diameter pipe
at 0.5m/s
2. A liquid of viscosity 3.2N.s/m2 and specific gravity 1.1 flows in a pipe of diameter
125mm.The pressure drop over a meter is 150N/m2. Calculate the frictional factor for the
pipe if the flow is in the laminar regime.
3 A pipe whose average roughness is 0.02mm is employed to raise water through a height of
10m.The pipe length is 100m and its diameter is 300mm.Calculate the power required for a
discharge rate of 30,000l/min.
4 Three pipes of diameter 300mm, 200mm and 400mm and lengths 450mm, 255mm and
315mm respectively are connected in series. The difference in water surface levels in two
tanks is 18m. Determine the rate of flow of water if coefficients of friction are 0.0075, 0.0078
and 0.0072 respectively considering cases of minor losses and neglecting minor losses.
5 When a sudden contraction is introduced in a horizontal pipe line from 500mm diameter to
250mm diameter, the pressure changes from 105kN/m2 to 69kN/m2.If the coefficient of
contraction is assumed to be 0.65, calculate the water flow rate. Following this, if there is a
sudden enlargement from 250mm to 500mm and if the pressure at the 250mm section is
69kN/m2, what is the pressure at the 500mm enlarged portion.
6
Reading List:
1 Darby4, R.(2001).Chemical Engineering Fluid Mechanics. Second Edition. Marcel
Dekker, Inc. New York. (pp. 149-184 ). ISBN 0-8247-0444-4
2 Ogboja2 ,O. (2005). Fluid Mechanics .UNESCO, Nairobi Kenya. (pp.279-326).ISBN 929158-000-7
3 Douglas1,J.F. & Gasiorek, J. M. (1997). Fluid Mechanics. Third Edition,Longman Press,
Singapore.(pp. 466-538 ) .ISBN 81-219-1667-4
Week 9-10:
Compressible Flows
Objective: Students should be able to describe the effects of pressure and temperature on fluid
density.
Description: Gas Properties, Energy equation for compressible flow,Isentropic
flow,Compressible flow in pipes.
Study Questions:
1
An ideal gas in which the pressure P is related to the volume V by the equation PV = 75
m2/s2 flows in steady isothermal flow along a horizontal pipe of inside diameter di, = 0.02
m. The pressure drops from 20000 Pa to 10000 Pa in a 5 m length. Calculate the mass flux
assuming that the Fanning function factorf= 9.0 X10-3.
2
Ethylene flows through a pipeline 10 km long to a receiving station A. At a point 3 km from
A, a spur leads off the main pipeline and runs 5 km to a receiving station B. The internal
diameter of the main pipeline is 0.20 m and that of the spur is 0.15 m. The flow rates into A
and B are regulated by valves at these locations. If the pressure immediately upstream of
valve A is 3.88 bar (absolute) and that at B is 3.69 bar when the flow rate into B is 0.63
kg/s, calculate the pressure at the beginning of the main pipeline, assuming that flow in the
pipeline is isothermal at a temperature of 20°C.
Data: specific volume of ethylene at 200C, 1 bar = 0.870 m3/kg, Fanning friction factor =
0.0045.
3 Calculate the air velocity in m / s required to cause a temperature drop of 1 K on a
conventional thermometer given that for the air at atmospheric pressure and 373 K, the
thermal capacity per unit mass at constant pressure Cp, = 1006 J/(kg K).
4
An ideal gas flows in steady state adiabatic flow along a horizontal pipe of inside diameter
di, = 0.02 m. The pressure and density at a point are P = 20000 Pa and  = 200 kg/m3
respectively. The
density drops from 200kg/m3 to 100kg/m3 in a 5m length. Calculate the mass flux assuming
that the Fanning friction factor f = 9.0 x 10-3 and the ratio of heat capacities at constant
pressure and constant volume = 1.40.
Reading List:
1 Darby4, R.(2001).Chemical Engineering Fluid Mechanics. Second
Dekker, Inc. New York. (pp. 267-291 ). ISBN 0-8247-0444-4
7
Edition. Marcel
2 Ogboja2 ,O. (2005).Fluid Mechanics .UNESCO, Nairobi Kenya. (pp.375-417).ISBN 929158-000-7
3 Douglas1,J.F. & Gasiorek, J. M. (1997). Fluid Mechanics. Third Edition,Longman Press,
Singapore.(pp. 626-676 ) .ISBN 81-219-1667-4
Week 11: Pumps and Compressors
Objective: Students have an understanding of the working principles of pumps and compressors.
Description: Pumps,Pump Characteristics,Pumping Requirements and Pump Selection,
Cavitation and Net Positive Suction Head (NPSH) , Compressors.
Study Question:
1
Calculate the available net positive section head NPSH in a pumping system if the liquid
density  = 1200 kg/m3. The liquid dynamic viscosity  = 0.4 Pa.s, the mean velocity u =
1 m/s, the static head on the suction side zs = 3m, the inside pipe diameter di, = 0.0526m,
the gravitational acceleration g = 9.81 m/s2 , and the equivalent length on the suction side
The liquid is at its normal boiling point. Neglect entrance and exit
2
losses.
A volute centrifugal pump has the following performance data at the best efficiency
point:
Evaluate the performance of an homologous pump which operates at an impeller speed of
29.2 rev/s but which develops the same total head h and requires the same NPSH.
3
A twin-cylinder, single-acting compressor, working at 5 Hz, delivers air at 515 kN/m2 at
the rate of 0.2 m3/s. If the diameter of the cylinder is 20 cm, the cylinder clearance ratio
5%, and the temperature of the inlet air 283 K, calculate the length of stroke of the piston
and the delivery temperature.
4
A single-stage double-acting compressor running at 3 Hz is used to compress air from
110 kN/m2 and 282 K to 1150 kN/m2. If the internal diameter of the cylinder is 20 cm,
the length of stroke 25 cm, and the piston clearance 5%, calculate:
(a) the maximum capacity of the machine, referred to air at the initial temperature and
pressure, and
(b) the theoretical power requirements under isentropic conditions.
5
In a single-stage compressor: Suction pressure D 101.3 kN/m2. Suction temperature D
283 K. Final pressure D 380 kN/m2. If each new charge is heated 18 deg K by contact
with the clearance gases, calculate the maximum temperature attained in the cylinder.
Reading List:
1 Darby4, R.(2001).Chemical Engineering Fluid Mechanics. Second Edition. Marcel
Dekker, Inc. New York. (pp. 239-266 ). ISBN 0-8247-0444-4
2 Ogboja2 ,O. (2005). Fluid Mechanics .UNESCO, Nairobi Kenya. (pp.463-510).ISBN 929158-000-7
8
3 Coulson4, J.M.,Richardson, J.F., Backhurst,J.R. & Harker, J.H. (2001).Chemical
Engineering Volume 3, Sixth Edition, Butterworth Heinmann Inc. Oxford.(pp. 109-124).
ISBN 0 7506 44950 X
Week 12: Mid Semester Test
Objective: To assess students’ mastery of the topics covered so far.
Description: Students will be tested on all the topics taken so far. This is to serve as a
preparation for the final examination at the end of the semster
Week 13 -14: Flow Measurement and Control.
Objective: Students should have an understanding of the construction and operation of the
hydraulic devices.
Description: The Pitot Tube,The Venturi and Nozzle,The Orifice Meter, Loss Coefficient,
Orifice Problems and Control Valves.
Study Question:
1 Briefly explain the operations of the following flowmeters: (i) The pitot tube (ii) The
orifice meter (iii) The venture meter (iv) The nozzle (v) The weir.
2 Sulphuric acid of density 1300 kg/m3 is flowing through a pipe of 50 mm internal
diameter. A thin-lipped orifice, 10 mm diameter, is fitted in the pipe and the differential
pressure shown by a mercury manometer is 10 cm. Assuming that the leads to the
manometer are filled with the acid, calculate (a) the mass of acid flowing per second, and
(b) the approximateloss of pressure caused by the orifice. The coefficient of discharge of
the orifice may be taken as 0.61, the density of mercury as 13,550 kg/m3, and the density
of water as 1000 kg/m3.
3 The rate of flow of water in a 150 mm diameter pipe is measured by means of a venturi
meter with a 50 mm diameter throat. When the drop in head over the converging section
is 100 mm of water, the flowrate is 2.7 kg/s. What is the coefficient for the converging
cone of the meter at that flowrate and what is the head lost due to friction? If the total loss
of head over the meter is 15 mm water, what is the coefficient for the diverging cone?
4 Water flows through an orifice of 25 mm diameter situated in a 75 mm pipe at the rate of
300 cm3/s. What will be the difference in level on a water manometer connected across
the meter? Viscosity of water is 1 mN s/m2.
5
What size of orifice would give a pressure difference of 0.3 m water gauge for the flow
of a petroleum product of density 900 kg/m3 at 0.05 m3/s in a 150 mm diameter pipe?
Reading List:
1 Darby4, R.(2001).Chemical Engineering Fluid Mechanics. Second Edition. Marcel
Dekker, Inc. New York. (pp. 293-333 ). ISBN 0-8247-0444-4
2 Ogboja2 ,O. (2005). Fluid Mechanics .UNESCO, Nairobi Kenya. (pp.515-556).ISBN 929158-000-7
3 Coulson4, J.M.,Richardson, J.F., Backhurst,J.R. & Harker, J.H. (2001). Chemical
Engineering Volume 1, Sixth Edition, Butterworth Heinmann Inc. Oxford.(pp. 243 -261).
ISBN 0 7506 4444 3
9
4 Coulson4, J.M.,Richardson, J.F., Backhurst,J.R. & Harker, J.H. (2001).Chemical
Engineering Volume 3, Sixth Edition, Butterworth Heinmann Inc. Oxford.(pp. 77-90).
ISBN 0 7506 44950 X
Week 15: Revision/ Tutorial Exercises
Objective:
This is to give students the opportunity to ask questions on all the topics covered in
the course.
Description: A general overview of the course will be made. Students are expected to seek
explanation on any difficult concept or topic treated during the course.
LEGEND FOR LIST OF BOOKS:
1
- Available in the University Library
2
- Available in local bookshops
3
- Available on the Web
4
- Personal collection
5
- Departmental library
10