Heat Engines Flashcards
They operate on a cycle.
heat engines
The best known reversible cycle is the?
Carnot cycle
these are devices or machines that produce work from heat in a cyclic process
heat engines
No process is possible which consists solely in the transfer of heat from one temperature level to a higher one.
CLAUSIUS STATEMENT
The efficiency of an irreversible heat engine is always ________ the efficiency of a reversible one operating between the same two reservoirs
less than
heat engines are devices or machines that produce __________________ in a cyclic process
work from heat
The Kelvin–Planck and the Clausius statements are _________________ in their consequences, and either statement can be used as the expression of the second law of thermodynamics.
equivalent
A _________________________________ is defined as one that completely eliminates friction and other dissipative forces to maintain motion forever due to its mass inertia
perpetual motion machine of the third kind
A _________________________________________ is a machine that there is only one heat reservoir involved, which is being spontaneously cooled without involving a transfer of heat to a cooler reservoir
perpetual motion machine of the second kind
examples of high temperature source
solar energy, oil furnace, nuclear reactor
Thermal energy reservoir a hypothetical body with a relatively large thermal energy capacity that can supply or absorb _______________ of heat without undergoing any change in temperature
finite amounts
The first law of thermodynamics requires that energy be ___________ during a process
conserved
A perpetual motion machine of the third kind is defined as one that eliminates friction and other dissipative forces to maintain motion forever due to its?
mass inertia
Thermal energy reservoirs are also called?
heat reservoirs
a reservoir that absorbs energy in the form of heat
heat sink
examples of heat source
Industrial Furnace or Boiler
A perpetual motion machine of the first kind produces work without the input of?
energy
A ____________________________________________________ produces work without the input of energy
perpetual motion machine of the first kind
The area bounded by the process curves represents the ______________ done by the system
net work
The Kelvin–Planck and the Clausius statements are equivalent in their consequences, and either statement can be used as the expression of the?
second law of thermodynamics
A heat engine operating as described in a ______________________ manner is very special and is called a Carnot engine.
completely reversible
The __________, thus the cycle efficiency, can be maximized by using processes that require the least amount of work and deliver the most, that is, by using reversible processes.
net work
They reject the remaining waste heat to a low-temperature sink
heat engines
a → b
Reversible Adiabatic Compression
a measure of the performance of a heat engine which is the fraction of the heat input that is converted to net work output
thermal efficiency
We have repeatedly stated that a process cannot take place unless it satisfies both?
first and second laws of thermodynamics
c → d
Reversible Adiabatic Expansion
A perpetual motion machine of the third kind is defined as one that completely eliminates ______________ and other _______________ to maintain motion forever due to its mass inertia
friction, dissipative forces
Any device that violates the Kelvin–Planck statement also violates the ______________________ , and vice versa
Clausius statement
Two conclusions pertain to the thermal efficiency of reversible and irreversible (i.e., actual) heat engines, and they are known as the?
Carnot principles
a hypothetical body with a relatively large thermal energy capacity that can supply or absorb finite amounts of heat without undergoing any change in temperature
Thermal energy reservoir
They convert part of this heat to work (usually in the form of a?)
rotating shaft
The characteristics of such an ideal engine were first described by __________________________ in 1824
Nicolas Leonard Sadi Carnot
Thermal energy reservoir is a hypothetical body with a relatively large ________________ capacity that can supply or absorb finite amounts of heat without undergoing any change in temperature
thermal energy
They receive heat from a high-temperature source
heat engines
No apparatus can operate in such a way that its only effect (in system and surroundings) is to convert heat absorbed by a system completely into work done by the system
KELVIN-PLANCK STATEMENT
Any device that violates either law is called a?
perpetual-motion machine
examples of heat sink
Bodies of water (oceans, rivers, etc), and Atmosphere
The second law of thermodynamics asserts that processes occur in a certain direction and that energy has ___________________ as well as _____________
quality, quantity
A perpetual motion machine of the second kind is a machine that there is only one _________________ involved, which is being spontaneously cooled without involving a transfer of heat to a cooler reservoir.
heat reservoir
The net work, thus the ________________, can be maximized by using processes that require the least amount of work and deliver the most, that is, by using reversible processes.
cycle efficiency
The efficiencies of all reversible heat engines operating between the same two reservoirs are?
the same
two types of thermal energy reservoirs
heat source and heat sink
They convert part of this heat to work
heat engines
The net work, thus the cycle efficiency, can be maximized by using processes that require the least amount of work and deliver the most, that is, by using _____________________
reversible processes
a reservoir that supplies energy in the form of heat.
heat source
d → a
Reversible Isothermal Compression
b → c
Reversible Isothermal Expansion
A heat engine operating as described in a completely reversible manner is very special and is called a?
Carnot engine
