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UrbanXrisis
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Can someone explain to me how Heat engines work?
Originally posted by UrbanXrisis
you see, I really don't get it. My physics teacher told me that heat engines formed a PV diagram...looked like a rectangle. There was an increase in pressure...he said it was abiabatic. Then increase in volume, he said it was isobaric. Then abiabatic, then isobaric. And now we are back at step one. My question is, in a PV diagram, how can you have a change in pressure when there is no heat added to it? What causes that change?
Originally posted by HallsofIvy
PV= NRT. Change the volume of course! (You do it slowly so that any temperature change conducts to the outside air.)
Originally posted by UrbanXrisis
Could you please explain the isothermal compression and expansion of the carnot cycle?
A rectangle on a PV diagram is inconsistant with these strok descriptions. Two opposing strokes (the isobars) will be parallel to each other on the PV diagram, but the adiabatic strokes will not be parallel (at least, I can't think of a case in which they both would be). In order to make a rectangle, you would need to replace the adiabats with isochors.Originally posted by UrbanXrisis
My physics teacher told me that heat engines formed a PV diagram...looked like a rectangle. There was an increase in pressure...he said it was abiabatic. Then increase in volume, he said it was isobaric. Then abiabatic, then isobaric.
A heat engine is a device that converts heat energy into mechanical work. It typically utilizes the principles of thermodynamics to transfer heat from a hot source to a colder sink, resulting in the production of useful work.
Heat engines work by utilizing a working substance, such as a gas or liquid, to absorb heat from a hot source and then release it to a colder sink. This transfer of heat causes the working substance to expand and produce mechanical work.
A heat engine produces work by transferring heat from a hot source to a colder sink, while a heat pump transfers heat from a colder source to a hotter sink. In other words, a heat engine is used to produce energy, while a heat pump is used to transfer energy.
There are two main types of heat engines: external combustion engines and internal combustion engines. External combustion engines, such as steam engines, use an external heat source to heat the working substance. Internal combustion engines, such as gasoline engines, use a fuel-air mixture that is ignited inside the engine to produce heat.
Heat engines have a wide range of practical applications, including power generation, transportation, and industrial processes. They are used in various forms, such as steam turbines, gas turbines, and internal combustion engines, to power vehicles, generate electricity, and produce heat for industrial processes.