PROBLEM 5.1 KNOWN: Electrical heater attached to backside of plate while front surface is exposed to convection process (T,h); initially plate is at a uniform temperature of the ambient air and suddenly heater power is switched on providing a constant q .
SP R &1M 2
TESTI
M l aE! : 1 ]
0
T H IS IS O P E N T EX T B O O K O N L Y T E ST
f s t a i n l e s s s t e e l i n i t i a l ly a t 6 2 o o c i s c o o l e d i n a i r
2 K
Fi n d t h e t i m e r e q u i r e d fo r t h e c e n t e r o f t h e
m
r e s u lt
Heat Transfer Project
Solar Water Desalinization System
Richard S Sherwin
Matthew Baquet
Spring 2015
Abstract
Solar desalinization is a process used to remove various particulates from water such as salts and
minerals, using the thermodynamic processes of
Heat Transfer Project
Solar Water Desalinization System
Richard S Sherwin
Matthew Baquet
Spring 2015
Abstract
Solar desalinization is a process used to remove various particulates from water such as salts and
minerals, using the thermodynamic processes of
ME 4433
Heat Transfer Project
Solar Desalinization
Group Members
Ryan Jarreau
Fuwei Chen
Austin Lee
Richard Sherwin
Abstract
Water desalinization involves the removal of salt and various minerals through several different
processes to produce fresh water.
Simplified heat transfer
Conduction
T T
T
q k
k 2 1
x
L
x
Convection
4
q Ts4 T
Contact
General
q
x
Hyperbolic Functions
1
h A
cosh ax
Rrad
T1 T2
Rt,c
1
2
A Ts2 T Ts T
Rcontact
q T R , q q A
First Law
Control Volume:
t
(When is this true?)
kA
Rconv
Definitions: 1 point each.
1. U (in comparison to h)
2. Logmean temperature
3. Grashof number
4. Nucleate boiling
5. Critical heat flux
6. Counter flow heat exchanger
7. Black Body
8. Transmissivity
9. Diffuse emission
10. View factor
Problem 1 (20 point
ME 4433 Radiation Problmes
Problem 1.
Estimate the wavelength corresponding to maximum emission from each of the following surfaces: the
sun, a Tungsten filament at 2500 K, a heated metal at 1500 K, human skin at 305 K, and a cryogenically
cooled metal su
:m
b
L
L
.:
l
a
.
C
v f
D

:
L
J
\
Uu
:
r
EL
s l 1u r t a l u m
1" 1= 2 0 W
u n tl
is
in
e
w
l c i s l e r ( hu r t s d i s c
T hc [ c
u m
t
)se
l i nder
d to
u s s t LI
in
o
f tl ia m
c te r
5c
a c tl n v c c t iv c e n v
c la ss
m
iro
an
d h e i g h
Terms to know for exam 1
1. Conduction
2. Heat flux (q)
3. Convection
4. Radiative heat transfer
5. q
6. q(dot) (Be able to list types)
7. Surface energy balance
8. Specific heat
9. Density
10. Conductivity
11. Thermal resistance
12. Contact resistance
13
P120 points: The temperature distribution ’1‘ (x, t] in degrees Celsius in the plane wall shown
below at one instant oftime t is given by
T (x, t): 180180x+25x2
where x is in meters.
Assuming that the surface at x=L is exposed at convective conditions:
emperature of
11L. A short aluminum cylinder of diameter Sam and height H=10cm is at an initial t
= 700C. Use the
Ti=ZOO°C and is exposed to a convective environment with h=525W/m2 DC and TD"
mCharts discussed in class to find:
(a) The temperature at a ra
Problem 1.1
Given:
[Difficulty: 3]
Common Substances
Tar
Sand
Silly Putty
Jello
Modeling clay
Toothpaste
Wax
Shaving cream
Some of these substances exhibit characteristics of solids and fluids under different conditions.
Find:
Explain and give examples.
S
1. U (in comparison to h)
2. Packed bed
3. Logmean temperature
4. Grashof number
5. Rayleigh number
6. Volumetric thermal expansion coefficient
7. Buoyancy
8. Free convection boiling
9. Nucleate boiling
10. Transition boiling
11. Film boiling
12. Critica
1. EXAM 1
a. Basic concepts
b. 1D steady conduction
c. Fin problems
2. EXAM 2
a. 2d steady conduction
i. Shape factors
b. 1d unsteady conduction
i. Series solutions, etc
c. Convection
i. External flow
1. Basic concepts
2. Flat plates
3. Other geometrie
Vocab (5 will be on the exam)
1. Nodal network
2. Biot Number (Give equation and meaning: h*L/k will not be on the equation sheet!)
3. Fourier number (Give equation and meaning)
4. Boundary layer
5. Boundary layer thickness (explain thermal and velocity)
Name:
Give a brief explanation of each of these terms. (2 pts each)
1. Logmean temperature
2. Grashof number
3. Nucleate boiling
4. Bond number
5. Counter flow heat exchanger
6. Black Body
7. Transmissivity
(1 pt )
Problem 1. (20 pts)
Radioactive wastes
1. U (in comparison to h) =? Velocity profile in comparison to HT coefficient
2. Packed bed a saturated porous medium that consists of a stationary solid phase through which a fluid flows.
3. Logmean temperature(LMTD) CH 11 Heat Exchangers. Used to det
Simplified heat transfer
Conduction
T T
T
q k
k 2 1
x
L
x
Convection
4
q Ts4 T
Contact
General
q
x
Hyperbolic Functions
1
h A
cosh ax
Rrad
T1 T2
Rt,c
1
2
A Ts2 T Ts T
Rcontact
q T R , q q A
First Law
Control Volume:
t
(When is this true?)
kA
Rconv
Name:
Give a brief explanation of each of these terms. (3 pts each)
1. Conduction
2. Radiative heat transfer
&
3. q (Define and give examples)
4. Contact resistance
5. Modes of energy storage in a molecule
6. Cause of TWA 800 accident
7. Lumped parameter
TABLEL OnedilnensionaI. Headystate solutions lo the heat
equation with no generation
Plane Wall Cylindrical Walla Spherical Walla
 02 T_ ii d_T _ ii 1? _
Heat equatlon dxz _ t] rdr(r arr) _ r2 r(r2 arr) _ 0
Temperature T TX T + ATM cfw_drg T _ A;r: l
Name:
Give a brief explanation of each of these terms. (2 pts each)
1. Convection
2. Radiative heat transfer
3. Ohmic heating
4. Contact resistance
5. Modes of energy storage in a molecule
6. Specific heat
7. How particles exchange energy in a gas
(1 poin