Heat Transfer & Passive Design

What is heat (värme) and how does it naturally flow?

The movement of thermal energy caused by a difference in temperature, moving from areas of higher temperature to areas of lower temperature.

What is conduction (ledning) and how does it transfer heat?

The transfer of thermal energy through direct physical contact where high-speed particles collide with slower ones.

What is convection (strömning) and how does it transfer heat?

The transfer of heat through the bulk movement of a fluid (liquid or gas) driven by changes in density.

What is radiation (strålning) and how does it transfer heat?

The transfer of energy via electromagnetic waves that does not require particles and can travel through a vacuum.

What is density (densitet) and how does it drive convection currents?

A measure of mass per unit volume; in convection, warmer fluids expand, become less dense, and rise.

What is a Passive House (passivhus) designed to do?

A building designed to maintain a comfortable temperature with minimal active heating or cooling by using natural energy sources.

What is insulation (isolering) and how does it work?

Materials or methods used to slow down heat transfer (like trapping pockets of air to stop conduction).

What are thermal bridges (köldbryggor) in house construction?

Weak points in a building's insulation framework that allows heat to escape rapidly via conduction.

What is shading (skuggning) and how is it used for passive cooling?

A passive cooling method using overhangs, blinds, or trees to block unwanted solar radiation in the summer.

What is an everyday example of a convection current?

Warm air rising above a radiator while cool air drops near the floor to take its place.

What is an everyday example of heat transfer via conduction?

Touching a cold window pane and feeling your hand get cold, or holding a metal spoon in boiling soup.

What is an everyday example of heat transfer via radiation?

Feeling the warmth of the Sun on your skin, or warming your hands near a campfire.

How do the principles of heat transfer apply to winter clothing?

Thick layers trap pockets of still air, which acts as a poor conductor (insulator) to minimize heat loss.

How do the principles of heat transfer apply to summer clothing?

Light colors reflect solar radiation, while loose garments allow air to circulate and remove heat via convection.

How does a vacuum flask design eliminate conduction and convection?

Uses a vacuum layer between walls to completely eliminate heat transfer because there are no particles to carry the energy.

What is thermal mass and how is it used to heat a building passively?

Thick concrete or tile floors that absorb solar radiation during the day and slowly release it via conduction and convection at night.