Solution
c. Explain in words the Continuum Approximation.
The assumption that at a large enough length scale (much greater than the molecular length
scale) a material or fluid may be treated as continuous and homogeneous, allowing us to treat
properties(e
ChE 3114: Fluid Transport
Homework #1 Solution
Due Friday August 30, 2013
1) Define the primary differences between a gas, liquid and solid. Be sure to define the differences
both macroscopically (in terms of response to bulk applied stress) and in terms
6.A - Momentum Analysis of Flow Systems
Linear Momentum
Angular Momentum
Topic 6 student Page 1
Choosing a control volume:
A control volume can be selected as
any arbitrary region in space through
which fluid flows, and its bounding
control surface can be
4.A Fluid Kinematics
Friday, July 06, 2012
1:16 PM
Fluid kinematics: The study of how fluids flow and how to describe fluid
motion.
LAGRANGIAN AND EULERIAN DESCRIPTIONS
Lagrangian description: To follow the path of individual objects.
This method requires
density
998 kg/m^3
Vdot1
viscosity 0.001002 kg/(m s)
L1
epsilon
Welect
D1
Za
Zb
Vdottotal
0.000045 m
8000 W
5m
e/D
V1
13 m
Re1
0.033 m^3/s
hpump
13.87865 m
Wcalc
0.03 m^3/s
36 m
L2
36 m
0.04 m
D2
0.08 m
0.001125
0.000563
2.387324 m/s
e/D
V2
95111.76
Re2
4
2.A - Fluid Properties
Continuum Approximation
Matter is made up of atoms (discrete units), but it is
more convenient to consider a substance as
continuous, homogeneous matter with no gaps - a
Continuum.
Physical Properties
Density and Specific Gravity
Li
7 DimensionalAnalysis
Enablesustoexpressrelationsbetweenvariablesin
termsofdimensionlessgroupsofvariables.
Nondimensional equation: If we divide each term in the equation
by a collection of variables and constants whose product has those
same dimensions,
5.A - General Balance Equations
We are generally interested in the conservation of three quantities:
We must define:
Interactions between the CV and surroundings are due
to:
Topic 5 Page 1
consider the following system
For a property X (mass, momentum or
9.A - Introduction to Microscopic Momentum Balances
1. Momentum balance within a volume element
consider
momentum:
two mechanisms for momentum to enter/leave volume element
1. molecular transport
2. convective transport
we can compose a momentum balance o
10.A - Compressible Fluid Flow in a Pipe
Compressible fluids (such as gases) require that we take
into account changes of density with pressure and/or
temperature.
Compressible flows frequently encountered in flow of
gases at very high speeds
Usually requ
8.A - Internal Flow
Tuesday, September 13, 2011
3:00 PM
Liquid or gas flow through pipes or ducts is commonly used in
heating and cooling applications and fluid distribution
networks.
The fluid in such applications is usually forced to flow by a fan
or
9.G - Flow Through a Pipe
Consider a fluid flowing through a cylindrical pipe:
assumptions:
1. Look at continuity equation (cylindrical coordinate - BSL B.4-2)
2. Look at equations of momentum
i. z - direction
simplifies to
ii. r - direction
iii. - direct
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9.K - Multidimensional Flow Problems
1. Recall that for general 3D flow we have 4 equations
and 4 unknowns
in Cartesian coordinates the unknowns are:
here:
2. To date, we have only solved very simple problems
e.g., falling film (Topic 3B)
3. Consider flow
3.A - Pressure of a Static Fluid
Pressure
- Fluids at rest are usually in a state of compression
- Pressure acts isotropically (independent of direction)
Topic 3 Page 1
1. Consider a column of water
What is the mass of the fluid?
What is the force exert
1.A - What is a Fluid?
What is a fluid?
Industrial uses of fluids
- Nearly every material we process is, at some point, a
fluid
Topic 1 Page 1
Need to understand laws that govern fluid flow
Fluid mechanics: The science that deals with the
behavior of flu
2. Solution
3. Solution
A clutch system is used to transmit torque through an oil film between two
identical disks. For specified rotational speeds, the transmitted torque is to be determined.
Assumptions 1 The thickness of the oil film is uniform. 2 The
ChE 3114: Fluid Transport
Homework #5
Due Friday, September 27th, 2013
Problems from the textbook are denoted by the chapter and problem number (i.e. 1 -2
chapter 1, problem 2.) All problems are from the 3rd edition. If you are using an earlier
edition,
ChE 3114: Fluid Transport
Homework #2 Solution
Due Friday, September 6th, 2012
Problems from the textbook are denoted by the chapter and problem number (i.e. 1 -2
chapter 1, problem 2.). Be sure to reference the 3rd edition of C&C!
1. C&C 2-39C
Solution
Problem3.(30points)
Averylargetankofwater(assumewaterdensityw=1000kg/m3)drainsthroughapipeanddischarges
fromanozzleasshowninthediagrambelow.Thetankisopentotheatmosphere,andthenozzle
dischargestotheatmosphere.ThegagepressureatpointAis25kPa.
1
H
A
DA =150mm