22.341 Heat Conduction & Radiation

Spring Semester 2000

Catalog Description: The theory of steady state and transient heat conduction in solids is developed and applied. The concepts of Biot and Fourier numbers are covered and their applications are studied. The principals of thermal radiation with application to heat exchange between black and non-black body surfaces are studied. The use of radiation networks (electrical network analogy) is examined. Surface radiation properties are extensively covered. Design projects are integrated into the course. Each design project is an open-ended problem with no unique solution -- requiring assumptions. The projects utilize heat transfer codes and other software tools.

Prerequisite: 22.242 (Thermodynamic), 92.234 (Differential Equation)

Textbook: J. P. Holman, Heat Transfer, McGraw Hill, 8th Edition, 1997.

Review Materials: Thermodynamics notes on first and second laws, thermodynamic properties and work. Math notes on gradient operator and general solution methodology of ordinary and differential equations.

Instructor: Majid Charmchi, Professor, Mechanical Engineering Department

Goal s:

To teach two-basic modes of heat transfer (i.e., conduction and radiation)

Heat diffusion mechanisms in solids, liquids and gases.
Surface temperature, surface temperature gradient and surface heat flux.
Surface radiation emission and surface radiation properties.
Net thermal radiation exchange between surfaces

To apply basic concepts to obtain heat transfer rates and temperature distributions for various heat transfer situations, and to analyze, design and optimize thermal systems.

To reflect current technologies such as electronic cooling, medical devices, insulation systems, materials processing, thermal measurement and process control.

Objectives: Upon completion of this course, the student will be able to:

Evaluate thermal conductivity of materials.
Determine surface temperature gradient and balance it against surface heat convection or a specified surface heat flux.
Model and solve one-dimensional, steady state heat conduction problems with or without internal heat source --plane wall and radial conduction in cylinders and spheres.
Obtain insulation thermal resistance values.
Solve heat diffusion in composite layers.
Model and solve heat dissipation through fins (conduction-convection systems).
Evaluate the overall heat transfer coefficient.
Apply conservation of energy to model unsteady state heat conduction.
Test for negligible conduction resistance --low Biot number (lumped-heat- capacity concept).
Solve transient heat conduction problems.
Apply the principals to design conduction-convection heat transfer system
Evaluate surface blackbody radiation.
Estimate surface radiation properties.
Evaluate view factors --geometrical relationship between surfaces.
Obtain radiation heat exchange between surfaces in an enclosure.
Apply the principals of radiation in design projects.

Prerequisites by Topic:

First and second laws of thermodynamics.
Thermodynamic properties.
Heat and temperature.
Solution of ordinary and differential equations.
Use of computer tools to perform engineering analyses

Topics covered:

Introduction of the basic modes of heat transfer (2 classes)
The energy equation, surface energy balance, the conduction rate equation (2 classes)
Thermal properties, heat diffusion equation, boundary and initial conditions (2 classes)
One-dimensional, steady-state heat conduction: plane wall and radial systems (3 classes)
Etended surfaces: fins and fin selection (2 classes)
Two-dimensional, steady-state heat conduction (3 classes)
Transient heat conduction; lumped heat capacity (2 classes)
Heisler charts (2 classes)
Radiation: fundamental concepts (1 class)
Blackbody radiation and radiation properties (3 classes)
Kirchhoff's Law and gray surfaces (2 classes)
View factors and blackbody radiation exchange (3 classes)
Radiation exchange between diffuse, gray surfaces (5 classes)
Multi mode heat transfer (2 classes)

Computer usage: For the analysis, the students are free to use MATHCAD or MATHLAB packages or to develop their own computer code using FORTRAN or C++ programming. Most students used MATHLAB package. In addition, the textbook has integrated a PC software package that allows the student to solve heat transfer problems with a minimum of repetitive arithmetic effort. In the design projects, all reports and graphical output are required to be computer generated.

Design Projects: Conduction and Radiation (22.341) is the first course of a two-course sequence in Heat Transfer subject. Design projects in form of open-ended problems are integrated in this course. Two design projects are assigned during a semester. Each project is related to the course material covered in class in the previous weeks. The projects address real industrial problems such as cooling of electronic devices, extrusion processes, radiation curing of coated surfaces, etc. The design projects require the student teams (2 or 3 students per team) to apply the recently covered course materials to problems that are different from those seen in their weekly homework. Each of these open-ended problems has no unique solution. The students are faced with sets of parameters and are asked to seek the optimum design solution(s). Brain storming among the team members is highly encouraged and the instructor is available for consultation. Each design team is required to deliver a well-written report. The report must include the design objectives, assumptions, analyses, data and graphs, result discussions, and conclusions. The project grade is based on the complete report elements and presentation, sound writing style, and the technical contents. Extra credit is given for creative design approaches and comprehensive result discussions and conclusions.

Evaluation:

Homework 10%

Midterm Examinations 40%

Design Projects 25%

Final Examination 25%

Professional Component:

This is the first course of a two-course sequence in Heat Transfer subject. The principles of conduction, convection, and radiation heat transfer are first introduced. The conservation of energy is revisited, but with special treatment of energy crossing the boundaries of a control volume. The meaning of surface temperature gradient, surface heat flux, convective heat transfer coefficient, and surface thermal emission are taught. The relationship between heat diffusion and temperature distribution in a medium is covered. Solutions to problems having internal heat source/sink are presented. Heat conduction under unsteady state condition is introduced and solution techniques for some simple, but common cases are taught. The fundamentals of thermal radiation are introduced and solution methods to several classes of problems are presented. These fundamentals and solution techniques are necessary for mechanical engineers to design and/or evaluate thermal systems, such as heat exchangers, HVAC systems, electronic packaging, etc. In this course, the design projects introduce the students to some real industrial problems, such as cooling of electronic devices, extrusion processes, and radiation curing of coated surfaces.

Program Objectives (numbers refer to section in SSR):

Informational content and homework contribute to fundamental knowledge (2.1-ii)
Informational content and projects contribute to experience in the integrated application of fundamental principals (2.1-iv)
Projects contribute to written communication skills (2.1-v)

Specific Objectives:

A student will be able to	Means to acquire	Means to assess and evaluate	ABET criteria	Program Goals	Bloom’s Taxonomy
Evaluate thermal conductivity of materials.	Lectures, reading, and homework	Homework, in class questions, quizzes	a, c, e	i, ii	1, 2, 3, 4, 6
Determine surface temperature gradient: surface heat convection, specified surface heat flux, and surface thermal emission.	Lectures, reading, and homework	Homework, in class questions, quizzes	a, c, e	i, ii	1, 2, 3, 4, 6
Model and solve heat conduction problems: one-dimensional, steady state problems with or without internal heat source --plane wall and radial conduction in cylinders and spheres.	Lectures, reading, and homework	Homework, in class questions, quizzes	a, c, e	i, ii	1, 2, 3, 4
Obtain insulation thermal resistance values.	Lectures, reading, and homework	Homework, in class questions, quizzes	a, e	ii, iv	1, 2, 3, 4, 6
Solve heat diffusion in composite layers.	Lectures, reading, and homework	Homework, in class questions, quizzes	a, c, e, k	ii, iv	1, 2, 3, 4, 6
Model and solve heat dissipation through fins and evaluate the overall heat transfer coefficient.	Lectures, reading, and homework	Homework, in class questions, quizzes	a, c, e, k	ii, iv	1, 2, 3, 4, 6
Apply conservation of energy to model unsteady state heat conduction, test for negligible conduction resistance (low Biot number cases, lumped-heat- capacity concept) and solve transient heat conduction problems.	Lectures, reading, and homework	Homework, in class questions, quizzes	a, c, e, k	ii, iv	1, 2, 3, 4
Apply the principals to design conduction-convection heat transfer systems.	Team research, in class consultation	Project report	a, c, d, e, g, i, j, k	ii, iii, iv, v, vi	1, 2, 3, 4, 5, 6
Evaluate surface blackbody radiation and estimate surface radiation properties.	Lectures, reading, and homework	Homework, in class questions, quizzes	a, c, e, k	ii, iv	1, 2, 3, 4
Evaluate view factors –geometrical relationship between surfaces.	Lectures, reading, and homework	Homework, in class questions, quizzes	a, c, e, k	ii, iv	1, 2, 3, 4
Obtain radiation heat exchange between surfaces in an enclosure.	Lectures, reading, and homework	Homework, in class questions, quizzes	a, c, e, k	ii, iv	1, 2, 3, 4
Apply the principals of radiation in design projects.	Team research, in class consultation	Project report	a, c, d, e, g, i, j, k	ii, iii, iv, v, vi	1, 2, 3, 4, 5, 6

ABET category content as estimated by faculty member who prepared description:

Engineering Science: 2 credits (2/3)

Design: 1 credit (1/3)

Prepared by: Majid Charmchi Date: January 2000