Heat engines Examples of Heat Engines – Steam engine – Coal plant – Nuclear plant – Automobile – Jet engine Each of these has – Hot source – Cold exhaust – Pathway from hot to cold that provides mechanical work Expanding piston steam engine, car engine Pressure difference across turbine blade
Heat Engines 1 Pathway from hot to cold that provides mechanical work – Expanding piston steam engine. – Pressure difference across turbine blade.
Heat Engines 2 Pathway from hot to cold that provides mechanical work – Expanding piston car engine. – Hot reservoir inside engine, cold reservoir tailpipe – “Internal combustion” engine.
Heat Engine Animations Otto Cycle (automobile) http://www.animatedengines.com/otto.html Otto Cycle (automobile) https://sites.google.com/site/physicsflash/home/otto
Refrigeration Basic Operation 1.Compress gas to high temperature/pressure 2.Cool and liquefy at high pressure (Q out) 3.Expand gas to low temperature/pressure 4.Warm and evaporate at low pressure (Q in) Thermodynamic cycle running backwards.
Forward and reverse Carnot cycle Forward Carnot cycle (heat engine) Q H in Work, Q L out Clockwise cycle Reverse Carnot cycle (refrigeration) Work, Q L in Q H out Counterclockwise cycle