Review - MEB
The equation
Control volume & inlet/outlet
Some pretty fantastic simplifications!
Some real-life applications
The relationships among energy, head,
power
Review - MEB
1. The Equation
P2 P1
g (h2 h1 )
V2 2 V12
Wp WT w
2
2
(2.18N)
2. Control
2.4 The Mechanical Energy
Balance
ChE 312
Lectures #12 through #15
29 Sept to 06 Oct 2014
The Mechanical Energy Balance
Most valuable and often-used tool for solving
real-life fluid flow problems
Is a combination of the 1st and 2nd Laws of
Thermodynamic
2.3. The Conservation of Mass
[Finite Control Volume] the Full
Story
Textbook: Section 5.1
With references to
Section 4.2.1. The Material Derivative
Section 4.3 Control Volume and System
Representations
Section 4.4 Reynolds Transport Theorem
ChE 312
Lectu
ChE 312
Lecture 22
Oct. 24 Agenda
Questions
Continue with Section 2.6:
Finish tube/pipe rheometry
Review Section 2.6
2.6.7 Calculation of major (straight pipe) losses (lw)maj for turbulent,
Newtonian pipeline flows
The integrated equations for laminar p
2.6.12 Friction losses in non-circular conduits
Text book Section 8.4.3
ChE 312
Lecture #27
05 Nov. 2014
Recall the force balance from Section 2.6.3
(Lecture 20)
This assumption
Consider incompressible, steady-state, horizontal pipe flow:
allows us to foc
2.6.11 Flow in branched pipelines or pipeline
networks
Textbook pp. 455-459
ChE 312
Lecture #26
03 Nov. 2014
Branch a
1
6
Branch b
Our goals:
Determine -P = (P1-P6)
Determine Qa and Qb
1
Electrical circuit analogy:
In a simple electrical circuit,
there
A note on vapourization in a
centrifugal pump
Vr = r
r
r
1
V1 = r1
1
V0 = Vpipe
0
0
* Neglect losses, PE *
MEB (0) to (r): Pr
Vr 2
In reality:
2
known
P0 V0 2
2
Pr not known
So, we compare NPSH-A to NPSH-R at plane (0) to
determine likelihood of vapouri
2.6.10 Calculation of minor losses (lw)min for flow
through fittings: entrances, enlargements,
contractions, valves, elbows
Textbook pp. 432-442
ChE 312
Lecture #25
31 Oct. 2014
Review: The Mechanical Energy Balance:
Vout
Pout Pin
g(hout hin ) out
2
2
i
Module 3
Fluid Transport System Analysis
* Textbook Section 3.7 (but isnt very good!)
* Textbook Ch. 12
* Additional material not from text
ChE 312
Lecture #28
7 Nov. 2014
3.1 Components of a pipeline system
Pipe & fittings
Pump(s)
Instrumentation
Pres
A note on hydrodynamic roughness ( or k)
Measured physical roughness
Hydrodynamic roughness
Different pipeline materials have different wall
roughnesses see Table 8.1 [and on eClass under
Data & Tables]
1
Our (ChE 312) Objective:
Recognize the numerous
Module 3 continued.
A note on friction factor and
system resistance curves
3.5. Centrifugal pumps
ChE 312
Lecture #30
14 Nov. 2014
The system resistance curve is often written in the form:
h sys (Q) A BQ 2
(2.55N)
Note that this assumes that the fricti
4.3 Terminal settling velocity
4.4 Hindered settling
4.5 Particle packing
4.6 Flow through packed beds
ChE 312
Lecture #34-36
24 28 Nov. 2014
4.3 Settling of a particle in an infinite
medium (Terminal settling velocity)
Direct applications:
Obtain a value
University of Alberta
Department of Chemical and Materials Engineering
ChE 312 Fluid Mechanics
Midterm Practice Exam
27 Oct. 2006
This exam should take you about 50 minutes.
Try to complete it with your books closed, using only the Equations sheet handed
University of Alberta
Department of Chemical and Materials Engineering
ChE 312 Fluid Mechanics
The Mid-Tenn Preparedness Quiz
23 Oct. 2006
Answer TRUE or FALSE to each of the following questions
1. Gauge pressures ONLY are to be used in the MEB
2. Gauge p
Newtonian fluid
w
Recall that:
8V
D
(2.42N)
V
rz
duz
dr
4 wL
D
(2.34N)
Q 1
uz dA
A A
A
uz
w
wR
r2
1 2
2 R
(2.36N)
rz r
w R
(2.35N)
2.6.6 Tube flow rheometer
Objective: use laminar tube flow experiments to determine the timeindependent rheology of
2.6 Fluid friction in steady, 1-D
flow in pipes and ducts
Textbook Ch. 8 pp. 400-460
ChE 312
Lecture #19
17 Oct. 2014
Objective
In the good old days:
lw known, solve for other term(s) in MEB
lw = 0
Determine lw by solving MEB
In this section, we lear
2.6.3 The relationship between lost work (
wall shear stress (w)
lw)
maj
and
2.6.4 The shear stress decay law
2.6.5 Laminar, Newtonian pipe flow
ChE 312
Lecture #20
20 Oct. 2014
2.6.3 The relationship between lost work (lw)maj
and wall shear stress (w)
Co
Flow Through Porous Media
A porous medium is a continuous solid phase that has many void spaces
or pores in it. Examples are: sponges, gravel, bricks, limestone, and
packed beds used for filtration and absorption.
Note: there is no chapter on porous media
Flow Through Porous Media
2. Flow through Packed Bed
The equation that
describe the pressure
drop vs. flowrate is
MEB between 1 and
2:
Q
1
2 1 2 2 1 2
+
+ (2 1 ) =
2
0
2
=
2
2
=
2
0
2
2 1
=
In order to describe D, we recall the concept of
the hyd
8.2 Fully Developed Laminar Flow in Pipe
Example:
rx
R
The wall shear stress in a fully developed flow portion of a 12in.-diameter pipe carrying water is 1.85 lb/ft2. Determine the
pressure gradient, where x is in the flow direction, if the
pipe is (a) ho
8.2 Fully Developed Laminar Flow in Pipe
g
MEB for a steady,
incompressible flow in a pipe:
(1)
2 1 2
+ 2 + 2
2
1 1 = 2 2
=
1 1 2
+ 1 + 1
2
A1 = A2
0
1 = 2
1
2
+ 1
+ 2 =
(2)
Fully developed steady flow in a
constant diameter pipe may be
driven by gr
We learned
Applied Mechanics
(study the response of materials
(solid or fluid) to external forces)
Fluid Mechanics
Fluid Statics
(fluid at rest)
Solid Mechanics
Fluid Dynamics
(fluid at motion)
ChE 312-Fluid Mechanics Winter 2014
1
4. Fluid Motion
4.1 Vel
Chapter 12. Turbomachines
Turbomachines are mechanical devices that either extract energy from a
fluid (turbine) or add energy to a fluid (pump) as a result of dynamic
interactions between the device and the fluid. While the actual design
and construction
5. Control Volume Analysis of Fluid Motion
5. Control Volume Analysis
The fluid behavior is governed by fundamental physical
laws that are approximated by an appropriate set of
equations. The application of laws such as:
the conservation of mass,
Newton
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5.3 Mechanical Energy Balance
1 2
+ +
2
1 2
+ +
2
=
Mechanical Energy Balance (MEB) for a steady,
incompressible flow.
is energy loss per unit mass [J/kg] due to frictional heat
and irreversibility and is either zero (frictionless flow)
8.4.1 Friction Losses in Non-Circular Conduits
Many of the conduits that are used for conveying fluids are not
circular in cross section. Although the details of the flows in such
conduits depend on the exact cross-sectional shape, many round pipe
results
8.5.2 Multiple Pipe System
The ultimate in multiple pipe systems is a network of pipes such as that
shown in above figure. Networks like these often occur in city water
distribution systems and other systems that may have multiple inlets
and outlets. The
5. Control Volume Analysis of Fluid Motion
The fluid behavior is governed by fundamental physical
laws that are approximated by an appropriate set of
equations. The application of laws such as:
the conservation of mass,
Newtons laws of motion,
the firs