Download Unit D: Topic 5 - Greater St. Albert Catholic Schools

Unit D: Topic 5
Hydraulic and Pneumatic Systems
Hydraulic Systems
• A closed system using a liquid under
pressure.
• Liquids are incompressible and transmit
pressure evenly in all directions.
Pneumatic Systems
• Use air instead of liquids.
• The air is not sealed in the device, but
sucked in from the environment by a
powerful motor and passes through the
device at high pressure where it escapes.
• Think of an air pump. The air in the pump
is compressed, raising its pressure and
forcing it into a ball with a lower pressure.
Pneumatics Cont’d
• Air will always go from an area of high
pressure to an area of low pressure.
• Examples of pneumatic systems include
hovercrafts, dentists’ drills, staple guns,
sandblasters, and jackhammers.
Circulatory System as Hydraulic
System
• Circulatory system is a closed, hydraulic
system:
• Heart = Pump – .moves blood throughout
body
• Blood = Fluid under pressure (120/80 Pa)
• Blood vessels = container
• Valves are movable parts which control
how much fluid can move through the
system.
Valves and Veins
- Valves are located in veins. When we
move our muscles blood is forced up
where a valve opens up above and closes
after they close.
- These valves do not let blood sink down to
the bottom of our bodies. They can only
move back up.