Reference & Information

Heat Transfer

The relationship between the Fahrenheit scale the Celsius scale, and the Rankine and Kelvin scales.
Fahrenheit, oF = 32.0 + (9/5)oC ..... Celsius, oC = (oF - 32.0)(5/9)
Rankine, oR = oF +460 ..... Kelvin, oK = oC + 273

Thermal Conductivity for Different metals
metal [Material] Symbol, Atomic Thermal Value
Silver Ag 4.08
Copper Cu 3.94
Gold Au 2.96
Aluminum Al 2.18
Beryllium Be 2.00
Tungsten W 1.74
Rhodium Rh 1.50
Molybdenum Mo 1.46
Chromium Cr 0.937
Nickel Ni 0.92
Platinum Pt 0.716
Tin Sn 0.666
Tantalum Ta 0.575
Lead Pb 0.353
Titanium Ti 0.219
Manganese Mn 0.078

Copper Wire Ampacity AWG Table for Copper Wire
Aluminum Wire Ampacity AWG Table for Aluminum Wire
Printed Wiring Board Information PWB Trace heating
Component Heat Derating

Military Climatic / Reliability Standards and Handbooks

Military Specifications

MIL-HDBK-310 - Global Climatic Data For Developing Military Products
- MIL-HDBK-310 divides the world into 5 regional types of climate: Basic, Hot, Cold, Severe Cold, and Coastal/Ocean.
Regional climatic data is provided as minimum and maximum temperatures with elevation and at altitude.
The frequency of occurrence for wind and min/max temperatures is also given.

World Climate Map shown below
MIL-STD-2218 - Thermal Design, Analysis and Test Criteria for Airborne Electronic Equipment
MIL-HDBK-217F - Reliability Prediction of Electronic Equipment
MIL-HDBK-217F Notice 2 - Reliability Prediction of Electronic Equipment
MIL-STD-1389D - Design Requirements for Standard Electronic Modules
Note the standards may be pulled from service at any time.

World map showing different climate regions
Global Climate Map

The world climate map shows the four basic climate regions as Hot, Basic, Cold, and Severe Cold.
Most of the worlds land masses are defined as Basic as defined by the DOD standard.
The map does not define the ocean regions, even though their shown as clear.

Ambient Temperature - Ambient temperature is the temperature immediately surrounding the equipment.
Ambient Cooled Equipment - Ambient cooled equipment dissipates its heat to its ambient environment (without ventilation induced by the vehicle). Equipment containing fans or blowers to circulate ambient air through the unit shall be classified as ambient cooled.
Design flow rate - Design flow rate is the minimum flow rate necessary to maintain all components within the unit at specified temperature requirements.
Forced (externally) cooled equipment - Forced cooled equipment is that equipment designed to be cooled by gas, including air and ram air, or liquid, supplied by the vehicle subsystems with sufficient pressure to flow through the unit and remove the dissipated heat.
Sea level ambient pressure and temperature - Sea level ambient pressure is defined as 14.7 psia + 5 percent. Sea level ambient temperature is defined as 59oF +2oF (15oC +1oC).
Stabilization - A stabilized thermal condition has been attained when the indicated temperature of the component with the largest thermal time constant varies at a rate less than 3.6oF [2oC] per hour.

Heat Sinks/Cooler Manufacturers: Mechanical Components-IC Accessories
Thermal Adhesive Manufacturers: Mechanical Components-Thermal Adhesive
Desiccant to absorb moisture.

PC motherboard

Distributor rolodex Electronic Components Electronic Equipment EDA CDROM Software Engineering Standards, BOB card Cabled Computer Bus Electronic Engineering Design Table Conversion DB9-to-DB25.
DistributorsComponents Equipment Software Standards Buses Design Reference

Modified 6/13/15
Copyright © 1998 - 2016 All rights reserved Larry Davis