Cooling Techniques for Electronic Equipment

Instructor: Steve Carlson - 2 Day Seminar

2 DAY SEMINAR

Don’t wait until your electronic equipment over-heats or fails because of poor cooling. Find out if your present systems are adequately cooled, how to avoid many common cooling problems and how to design efficient, reliable cooling systems for many different types of electronic cabinets.

The purpose of this course is to show designers and engineers quick methods for designing electronic equipment to withstand severe thermal environments without failing. Techniques are presented which will permit the evaluation and design of cost effective, compact cooling systems, without the aid of a large digital computer.

Learn simple design rules and guidelines, which can improve the effective cooling of your sophisticated electronic components used in today’s military, industrial and commercial electronic systems.

Learn methods for determining thermal stresses in lead wires and solder joints due to a mismatch in thermal expansions.

This course is based upon the popular book Cooling Techniques for Electronic Equipment by Prof. Dave Steinberg.

Questions are encouraged during the course, to make sure each participant understands the design techniques and applications presented.

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WHO SHOULD ATTEND

R&D Electronic Engineers and Managers
Packaging Engineers
Quality & Reliability Engineers
Test Engineers
Manufacturing Engineers
Mechanical Engineers
Application & Sale Engineers

COURSE OUTLINE

Electronics Cooling Background

· Heat Transfer within Electronic Systems

o Conduction

o Natural and Forced Convection

o Radiation

· Types of Thermal Analyses

o Steady-State and Transient

· Common Electrical Components and their Construction

· Types of Electronic Enclosures

o Manufacturing and Sealing

· Material Properties

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Practical Conduction Cooling Design Guidelines

Calculate Temperature Rise
Concentrated Heat Loading
Uniform Heat Loading
Determine Heat Flow
Tracing a Heat Conduction Path from Heat Source To Sink
One and Two Dimensional Resistor Networks
Parallel and Series Heat Flow
Printed Circuit Boards (PCB)
Determine Component Junction Temperature
Calculating Thermal Impedance from Case to Board (θcb)
Identifying Thermal Impedance from Junction to Case (θjc)
Using Internal Ground and Voltage Planes to Spread Heat
Calculate Effective PCB Thermal Conductivity
Mounting High Power Components on Circuit Boards
Simple Methods for Adding Circuit Board Heat Sinks
Calculate Thermal Interface Impedance
Bolted Contact Resistance
Effects of Surface Finish, Hardness and Pressure on Interface Resistance
Improving Heat Transfer with Thermal Interface Materials
Effects of Altitude on Interface Resistance
Thermal Resistance Across Different Board Edge Guides
Many Sample Problems to Promote Better Understanding

Mounting Various Types of Components on Circuit Boards

· Problems with Surface Mounting Components

o Leadless Chip Carriers, Transformers, Ball Grid Arrays, Large Multi-Chip Modules, and Large Fine Pitch Leaded Components

· Problems with Through Hole Mounting Components

o Avoid Flush Mounting

o Pin Grid Arrays

o Small Axial Leaded Resistors

· Lead Wire Strain Relief

o Various Types Of Lead Wire Strain Relief To Prevent Solder Failures

o Adding Thermal Compression Bonded J Leads To Chips

o Vapor Phased Soldering S Wires To Surface Mounted Parts

o Avoiding Cracking of Chip Resistors and Capacitors

· Case Histories on Successes and Failures

Effective Natural Convection and Radiation Cooling

Free Convection
Cooling Vertically Oriented Circuit Boards
Cooling Horizontally Oriented Circuit Boards
Required Spacing Between Circuit Boards for Good Cooling
How Altitude Effects Natural Convection Cooling
Finned Heat Transfer Surfaces
Adding External Fins on a Box To Improve Cooling
Adding Cooling Fins on Hot Components
Making Effective Use Of Extruded Fin Heat Sinks
Methods For Increasing Convection And Radiation Coefficients
Combining Convection And Radiation Cooling
Effects of Solar Energy on Outdoor Electronics
Radiation Heat Transfer
Solar Radiation and Albedo Effects
Cooling Within Vacuum of Space
Many Sample Problems To Demonstrate Practical Applications

Methods for Improving Forced Convection Cooling

· Cooling Fans

o Various Types of AC and DC Cooling Fans

o Air Flow Properties of Fans and Blowers (Fan Curve)

o Effects of Altitude on Mass Flow and Pressure Drop

o Working with Sigma Delta Pressure Drop

· Fan Location

o Typical Problems with Improper Fan Installation

o How To Determine and Cure Short Circuit Cooling Air Flow Path

· Flow Losses

o Calculating Pressure Drops Through A Chassis

o Understanding Static, Velocity and Total Pressure

o Flow Losses Due to Entrance, Exit, Expansion and Turns

· Fan Selection

o Matching the Impedance Curves for Chassis and Fan

· Convoluted Fin and Pin Fin Heat Exchanger Performance

· Many Sample Problems to Illustrate Cost Effective Applications

Practical Design and Analysis Guidelines

· Hand-calculations confirm Finite Element Analysis results

· How to Avoid Common Heat Pipe problems

· Various Liquids for Improved Cooling

· Chimney Equations for Improved Cooling of Large Cabinets

· Series-Parallel Air Flow Networks

· Humidity and Moisture Effects

· Environmental Stress Screening Guidelines

· Coefficient of Thermal Expansion

o Thermal Expansion Equilibrium Equations, Lead Wires, Solder

o Slow Thermal Cycling Solder Creep Forces, Stresses, Fatigue Life

· Case Histories to Promote Improved Electronic Design

INSTRUCTOR

Steve Carlson is a Mechanical Engineer Analyst at Northrop Grumman Navigation Systems Division in Woodland Hills, CA. He received his BSME at Arizona State University and MSME at California State University Northridge and has expanded the classical techniques developed by Professor Dave Steinberg to include Solid Modeling and Finite Element Analysis to reduce analysis time, improve accuracy, and decrease product development time.

He has worked on the mechanical design, analysis, testing and packaging of cost effective sophisticated electronic equipment that must work with a high degree of reliability in harsh thermal, thermal cycling, vibration and shock environments. He has been involved in these areas related to commercial, industrial and military applications for many years. He is the Principal Engineer at Carlson Mechanical Engineering and has provided consultant services to multiple companies in the areas of heat transfer, sine/random vibration, and computational fluid dynamics.

Mr. Carlson has worked on many aircraft, missile, and space programs for Litton G&CS, Northrop Grumman, and the Jet Propulsion Laboratory. These include the F-14, F-15, F-16, F-22, cruise missile, AMRAAM, Mars Science Laboratory (MSL), Gravity Recovery and Interior Laboratory (GRAIL), and Juno.

COST

Two-Day Course: $1,195 (U.S. Dollars) Payment is due by seminar date. We take VISA, MasterCard and American Express.

Register through our website or via e-mail: [email protected]