We are plotting two different Nu correlations for circular cylinders in cross flow. Eq. 7.52 is a standard
correlation used for Pr 0.7 and the ReD listed in Table 7.2. Eq. 7.54 is a correlation which covers the
entire range of ReD for which there exists d

UTF Links for Homework 7
1.
Related to problem A. This is a neat video of what flow around a cylinder looks like for low Reynolds number flow.
Figure 1: Snapshot of low-Re flow around a cylinder
http:/www.youtube.com/watch?v=rbMx2NMqyuI&feature=related
2.

UTF Links for Homework 9
1.
Related to problem 9.35. This website, from the Department of Energy, discusses the different kinds of
insulation available for air ducts. Typically, the insulation is made out of either fiberglass or mineral wool. The
website

UTF Links for Homework 6
1.
Related to #7.54. This website from IBM research discusses how convection cooling is used to
cool computer chips.
http:/www.zurich.ibm.com/st/cooling/convective.html
Figure 1: Distributed return architecture with cross section

UTF Links Homework 4
1.
Here is an interesting Excel spreadsheet available from the website of a professor at the
University of Virginia calculation of view factors. Try to play around with the dimensions for the
different shapes to see how changing diffe

PROBLEM 9.63
KNOWN: Horizontal pin fin of 6-mm diameter and 60-mm length fabricated from plain carbon steel (k
= 57 W/mK, = 0.5). Fin base maintained at Tb = 150C. Ambient air and surroundings at 25C.
FIND: Fin heat rate, qf, by two methods: (a) Analytica

PROBLEM 13.47
KNOWN: Cavities formed by a cone, cylinder, and sphere having the same opening size (d) and
major dimension (L) with prescribed wall emissivity.
FIND: (a) View factor between the inner surface of each cavity and the opening of the cavity; (b

PROBLEM 11.17
KNOWN: Inlet temperatures of pharmaceutical product and water in a concentric tube heat
exchanger. Tube diameters and fluid velocities.
FIND: (a) Value of the overall heat transfer coefficient, U, (b) Mean outlet temperature of the
pharmaceu

PROBLEM 8.14
KNOWN: Geometry and coolant flow conditions associated with a nuclear fuel rod. Axial
variation of heat generation within the rod.
FIND: (a) Axial variation of local heat flux and total heat transfer rate, (b) Axial variation of
mean coolant

PROBLEM 7.85
KNOWN: Velocity and temperature of combustion gases. Diameter and emissivity of thermocouple
junction. Combustor temperature.
FIND: (a) Time to achieve 98% of maximum thermocouple temperature rise, (b) Steady-state
thermocouple temperature, (

PROBLEM 12.37
KNOWN: Metallic surface with prescribed spectral, directional emissivity at 2000 K and 1 m (see
Example 12.7) and additional measurements of the spectral, hemispherical emissivity.
FIND: (a) Total hemispherical emissivity, , and the emissive

24-322 Heat Transfer, Fall 2015 HW#2
Assigned: September 10, 2015
Due: September 17, 2015 (at the beginning of class)
A. The 1-D, steady-state, constant properties conduction energy equation in a cylinder with
no energy generation/conversion is
1 d dT
r

PROBLEM 6.38
KNOWN: Flow over a flat plate. Velocity and temperature of two fluids. Variation of boundary
layer thickness with x for laminar flow.
FIND: (a) Location where transition to turbulence occurs for each fluid, (b) Plot of velocity boundary
layer

PROBLEM 1.15
KNOWN: Thickness, diameter and inner surface temperature of bottom of pan used to boil
water. Rate of heat transfer to the pan.
FIND: Outer surface temperature of pan for an aluminum and a copper bottom.
SCHEMATIC:
ASSUMPTIONS: (1) One-dimens

UTF Links for Homework 8 & Test 3 Review
1.
Related to HW 8, problem 8.51. This website is from Idaho National Laboratory. It discusses a gas-cooled
fast nuclear reactor. http:/www.inl.gov/research/gas-cooled-fast-reactor/
Figure 1: Gas-cooled nuclear rea

PROBLEM 13.55
KNOHN: Enlissivities. diameters and temperatures of concentric spheres.
FDID: (a) Radiation transfer rate for black surfaces. (b) Radiation transfer rate for difise-gray surfaces,
(-2) Effects of increasing the diameter and assuming blackbo

PROBLEl-I 12.70
1150113: Isothermal enclosure at a uniform temperature provides a known irradiation on two small
surfaces whose absorption rates have been measured.
FDID: (a) Net heat transfer rates and temperatures of the two surfaces. (b) Absorptivir

PROBLEM 9.1?
KNDWN: Dimensions of verticai plate. Plate and ambient temperatures.
FIND: Preferred orientation to minimize convective heat transferand convective heat transfer rate for
that orientation.
SCHEMATIC:
_T_
0.25 m
_l_
0.5 m
i
ASSUMPTIONS

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PREFEIIM 3.131
I'll-WHEN: Thermal conductivith and diameter afa pin n Value af the heat transfer eaefeient and
n efciency.
FIND: (a) length afn, {tr} Fin eectiveness.
SCI-[EILHTICE
.EELlfFNS: {1] Steady-state: sne-djrmnsisnal enndisns, {2} Negligibl

24-322 Fall 2011 Lab #1: Transient Conduction
Due: October 4 at the beginning of class.
Objective: Analyze the temperature-time data for the pure aluminum sphere in order to predict
convection coecients.
The sphere has diameter d = 0.024 m. Evaluate prope

x, gut/52; ohm 2m War 43% gamma/us A
lam UVCC Ah?
> r 23 R3 1
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PROBLEM 3.126
KNOWN: Dimensions and thermal conductivity of a gas turbine blade. Temperature and convection
coefficient of gas stream. Temperature of blade base and maximum allowable blade temperature.
FIND: (a) Whether blade operating conditions are acce