1. Ch. 16 Sec. 3
Using Heat

2. Heating Systems
Most homes & public buildings contain some kind of heating system.
In the simplest and oldest heating system, wood or coal is burned in a stove.

3. Forced-Air Systems Use fans to circulate warm air: Convection
Filtered and cleaned as it passes through out the system

4. Radiator Systems
A radiator is a closed metal container that contains hot water or steam.
The thermal energy contained in the hot water or steam is transferred to the air surrounding the radiator by conduction.
This warm air then moves through the room by convection.

5. Electric Systems
An electric heating system has no central furnace – Space heater
Instead, electrically heated coils placed in floors and in walls heat the surrounding air by conduction.
Heat is then distributed through the room by convection.

6. Solar Heating Systems Passive Solar Heating
Absorb radiant energy from Sun.
Active Solar Heating
use solar collectors that absorb radiant energy from the Sun.

7. Heat Engines A device that converts heat into work is a heat engine.
A car’s engine converts the chemical energy in gasoline into heat.
The engine then
transforms some
of the thermal
energy into work
by rotating the
car’s wheels.

8. Internal Combustion Engines
Four-stroke cycle engine
Intake Stroke
Compression Stroke
Power Stroke
Exhaust Stroke

9. Heat Movers
Device that removes thermal energy from one place and transfers it to another place at a different temp.
Ex. Refrigerator, air
conditioners, de-
humidifiers, heat
pumps.