University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
1. Conceptual Model for Diffusion
Diffusion is defined as the net transport due to random motion. A model for diffusive
flux can be constructed from the following simple example. Consider a onedimensional
system with motion in the X direction only. An in
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
10 Analysis of pipe flows
The Moody chart
.
Experiments were carried out to plot f against ReD and /D.
This results in a chart which depict lines of constant /D in
a fReD plots. This is the well known Moody chart as
shown in Figure 8.20
In the design of
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
9. Viscous Flow in a Pipe
This topic is about flow of fluid (mostly liquid) inside a
pipe. There are two characteristics of this type of flow:
Poiseuille
is
a
laminar flow (which has a special name called Poiseuille
medical doctor who
flow and turbulent f
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
7. Control Volume Analysis
 Energy Conservation.
Section 5.3
The Energy Equation for Control Volume
We will make a simpler approach in the derivation of the
Energy Equation.
Where V is the
Consider a control surface that encloses a certain system as disp
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
6. Control Volume Analysis
 Continuity Condition
There are two equations that we will apply in the control
volume analysis:
(a) The equation for continuity and
(b) The equation for fluid momentum.
The continuity equation
Section 5.1
This has been discuss
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
5. Fluid Kinematics
In this chapter, we will be studying the equations for fluid Ch 4
acceleration and the general equations that apply to
control volume analysis.
The Eulerian frame of reference
The properties of a flowing fluid, such as velocity and
pre
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
4. The Bernoulli Equation
Introduction
Here we are concerned with the Bernoulli equation for
steady flow. There is a version of Bernoulli equation for
unsteady flow which is out of the scope of this study.
The Bernoulli equation relates the pressure and v
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
School of Engineering and Information Technology
ENG243 Fluid Mechanics Study Guide
To be used in conjunction with the textbook:
by Munson, Young, Okiishi & Huebsch.
Fundamental of Fluid Mechanics 6th Edition
By W. K. Soh & J. Mitroy
ENG243 Fluid Mechanic
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
ENG247 ASSIGNMENT #1
This assignment is due 0900 Tuesday April 9rd at the start of my ENG247 lecture.
Alternately, the assignment may be delivered to my office before that time. The overall
weighting of this assignment to your final grade is 5%. Late assi
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
ENG243 FLUID MECHANICS TRIAL EXAMINATION
SEMESTER YEAR LECTURER SCHOOL TIME (in minutes): 1 2006 Jim Mitroy Engineering and Logistics [10 minutes] [180 minutes] [190 minutes]
Time for reading Time for working TOTAL TIME
INSTRUCTIONS TO CANDIDATES: 1. A sc
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
1
6. Continuous Release  Point Source
A scalar released continuously into a moving fluid and from a discrete point will form a
plume that grows in the lateral dimension through diffusion and extends downstream via
advection. Because the concentration pro
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
1
7. Basics of Turbulent Flow
Whether a flow is laminar or turbulent depends of the relative importance of fluid friction
(viscosity) and flow inertia. The ratio of inertial to viscous forces is the Reynolds number.
Given the characteristic velocity scale
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
1
9. Reactions and Exchanges
9.1 ReactionAdvectionDiffusion Solutions
In this chapter we consider how chemical reactions enter the massbalance equation as
distributed source and sink terms, S.
C
C
C
C
C
C
C
+u
+v
+w
=
Dx
+
Dy
+ Dz
S
t
x
y
z x
x y
y z
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
1
4. Boundary Conditions
When a diffusing cloud encounters a boundary, its further evolution is affected by the
condition of the boundary. The mathematical expressions of four common boundary
conditions are described below.
Specified Flux: In this case th
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
1
5. Advection and Diffusion of an Instantaneous, Point Source
In this chapter consider the combined transport by advection and diffusion for an
instantaneous point release. We neglect source and sink terms. For isotropic and
homogeneous diffusion the tra
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
1
8. Shear Dispersion.
The transport models and concentration field solutions developed in previous sections
assume that currents are spatially uniform, i.e. u f(x,y,z). However, spatial gradients of
velocity, known as shear, must exist close to a boundar
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
2. Conservation of Mass
The equation of mass conservation expresses a budget for the addition and removal of
mass from a defined region of fluid. Consider a fixed, nondeforming volume of fluid,
V , called the control volume (cv), which has a defined surf
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
1
3. Diffusion of an Instantaneous Point Source
The equation of conservation of mass is also known as the transport equation, because it
describes the transport of scalar species in a fluid systems. In this and subsequent
sections we consider analytical s
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
1
10. Introduction to the Transport of Particles
Small, neutrally buoyant particles exactly follow the fluid flow, (u, v, w), such that their
transport is described by the same equation used for dissolved chemicals. Particles
whose density deviates from t
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
ENG 243 Fluid Mechanics Study Guide
General These notes are intended as a summary of the ENG 243 Fluid Mechanics course for 2005 only. The important notes from each section of the course will be highlighted here and will assist you with preparation and st
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
SELT
Student Experience of Learning and Teaching
Teacher Internal (Higher Education) Analysis: 30720060526131247
Unit Code:
Unit Name:
Unit Level:
ENG243
Unit Details:
Fluid mechanics
Year 2
Teacher:
Dr Jim Mitroy
Academic Year:
2006
Academic Period:
Seme
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
SELT
Student Experience of Learning and Teaching
Unit Internal (Higher Education) Analysis: 30320060526124444
Unit Code:
Unit Name:
Unit Level:
ENG243
Unit Details:
Fluid Mechanics
Year 2
Teacher:
Dr Jim Mitroy
Academic Year:
2006
Academic Period:
Semeste
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
Unit Information
ENG243 Fluid Mechanics (Semester 1, 2012)
Credit points:
Assumed
knowledge:
Prerequisite(s):
Year:
10
Knowledge of
structures equivalent
to ENG101 Statics
and knowledge of
mathematics
equivalent to SMA102
Mathematics B
None
Mode:
Location
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
ENG243  Fluid Mechanics  Practical Classes
General Information
The laboratory section of ENG243 will be held in the laboratory located in Purple 2. Attendance
at the class is compulsory, so if you need to miss a class you should see the instructor first
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
Section One Research and Background Theory
1.
(10 Marks)
Discuss the origins of turbulence and the mechanisms that promote transition from laminar to turbulent flow in both external and internal flows.
2.
(5 Marks)
What is separated flow and how may one e
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
Section One Research Theory
Instructions: Answer any two of the four questions in section one
1.
(10 Marks)
Discuss the origins of turbulence and the mechanisms that promote transition from laminar to turbulent flow.
2.
(10 Marks)
Discuss the various form
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
ENG243 FLUID MECHANICS FINAL EXAMINATION
SEMESTER YEAR LECTURER SCHOOL TIME (in minutes): 1 2006 Jim Mitroy Engineering and Logistics [10 minutes] [180 minutes] [190 minutes]
Time for reading Time for working TOTAL TIME
INSTRUCTIONS TO CANDIDATES: 1. A sc
University of Zagreb Faculty of Electrical Engineering and Computing
Fluid mechanics
ENG 234

Spring 2013
UNIT CODE
UNIT NAME
LECTURER
WHAT ARE THE STRENGTHS OF THIS UNIT
THIS UNIT COULD BE CHANGED IN THE FOLLOWING WAYS TO IMPROVE MY LEARNING
LEARNLINE COULD IMPROVE MY LEARNING BY
ENG243
Fluid Mechanics
Jim Mitroy
ENG243
Fluid Mechanics
Jim Mitroy
ENG243
Flui