Heat Transfer

Heat is a measure of the total energy in a system and the kinetic energy of

Temperature is a measure of the average kinetic energy of a system.

Heat transfer is the transfer of heat energy from one source to another.

The transfer of heat energy can occur in three primary ways: Conduction, Convection and Radiation

Heat transfer is the transfer of heat energy from one source to another.

Conduction occurs when heat is transferred between particles that are in contact with each other.

Heat energy is transferred from molecules with more vibration (hotter) to those with less vibration (cooler).

Convection occurs in objects that “flow.” Warm air/liquids rises and cool air/liquids fall due to density change. This creates a ‘convection current.’

Requires physical contact of particles.

Radiation is when heat energy travels as a wave in a straight line through empty space.

Does NOT require contact. Several kinds of radiation.

Radiation waves vary in wavelength and frequency. Simple waves have several primary parts.

Simple Waves

Thermal conductors are substances that are able to internally transfer heat quickly. (ie gold, copper, aluminum, etc.)

Thermal insulators are substances that slow the rate of heat transfer. **Heat transfer cannot be stopped, only slowed.

Heating Loss in the Home

Heating Loss in the Home

Desert Architecture works by preventing radiated light energy from entering the structure. Doing so prevents heat entering the internal space.

Igloos use packed snow as their bricks (not ice) since the air pockets inside are good insulators.

A separate elongated doorway prevents heat loss to the outside.