What is a thermodynamic power cycle?
A power cycle consists of a series of repeating thermodynamic processes along a closed process path, while heat is converted into mechanical work The most widespread working medium is water The power cycle involves the water’s change of phase from a liquid state into superheated steam
What is meant by thermodynamic process?
A thermodynamic process is defined as a change from one equilibrium macrostate to another macrostate The initial and final states are the defining elements of the process In this process energy may be transferred form or into the system and also work can be done by or on the system
What is ideal thermodynamic cycle?
Ideal cycles are simplified thermodynamic closed cycles to analyze the compression, combustion, and expansion process in an engine with a focus on extraction of work from combustion of the fuel–air mixture
What are the types of cycle in thermodynamics?
Two primary classes of thermodynamic cycles are power cycles and refrigeration cycles Power cycles are cycles that convert a heat input into a work output, while refrigeration cycles transfer heat from low to high temperatures using work input In this chapter the emphasis will be on power cycles
What is thermodynamic cycle or cyclic processes?
In a cyclic process, the system starts and returns to the same thermodynamic state The net work involved is the enclosed area on the P-V diagram If the cycle goes clockwise, the system does work A cyclic process is the underlying principle for an engine
What are the four thermodynamic cycles?
Classification of Thermodynamic Cycle Reversible Cycle In a reversible process, there should be no loss of heat due to friction, conduction or radiation, etc Irreversible Cycle Isothermal and Adiabatic Constant Volume, Constant Pressure and Constant pv Throttling Note: 1# Carnot Cycle #2 Stirling Cycle
How many cycles are there in thermodynamics?
The following classification of thermodynamic cycles is made according to their constituent thermodynamic processes In practice, simple idealized thermodynamic cycles are usually made out of four thermodynamic processes In general, the following processes usually constitute thermodynamic cycles: Adiabatic process
What is the difference between process and cycle in thermodynamics?
In thermodynamics, a “process” is defined by a trajectory in thermodynamic state space from a starting point A to the end point B, and a “cycle” is just a closed trajectory going back to A Now, there is freedom of choice of the in-between states that the system undergoes
What is thermodynamic path?
A process is defined as the path of thermodynamic states which the system passes through as it goes from an initial state to a final state Understanding the nature of the process path is very important as heat and work depend on the path
What is the most efficient thermodynamic cycle and why?
Classical thermodynamics indicates that the most efficient thermodynamic cycle operating between two heat reservoirs is the Carnot engine [1] , and a basic theorem expresses that any reversible cycle working between two constant temperature levels should have the same efficiency as a Carnot cycle [2]
What are thermodynamic properties?
Thermodynamic properties are defined as characteristic features of a system, capable of specifying the system’s state Some constants, such as the ideal gas constant, R, do not describe the state of a system, and so are not properties “Specific” properties are expressed on a per mass basis
What is the difference between Otto cycle and diesel cycle?
The Otto cycle has less compression ratio (7:1 to 10:1) but in diesel cycle the compression ratio is high (11:1 to 22:1) In Otto cycle as well as in diesel cycle heat rejection takes place at constant volume The efficiency of Otto cycle is less as compared with the Diesel cycle
What is the difference between Otto cycle and Carnot cycle?
A Carnot engine is, simply, a reversible engine acting between only two heat reservoirs By contrast the Otto cycle, which has heating at constant volume, would need a whole series of heat reservoirs at incrementally higher temperatures to carry out the heating reversibly
What thermodynamic cycle is used for power plants?
The Rankine cycle or Rankine Vapor Cycle is the process widely used by power plants such as coal-fired power plants or nuclear reactors In this mechanism, a fuel is used to produce heat within a boiler, converting water into steam which then expands through a turbine producing useful work
What do you understand by thermodynamic equilibrium?
Thermodynamic equilibrium, condition or state of a thermodynamic system, the properties of which do not change with time and that can be changed to another condition only at the expense of effects on other systems
What is meant by thermodynamic state?
In thermodynamics, a thermodynamic state of a system is its condition at a specific time; that is, fully identified by values of a suitable set of parameters known as state variables, state parameters or thermodynamic variables Usually, by default, a thermodynamic state is taken to be one of thermodynamic equilibrium
What are the four 4 thermodynamic processes of an ideal Carnot heat engine cycle What is common to all four thermodynamic processes?
A Carnot cycle is defined as an ideal reversible closed thermodynamic cycle Four successive operations are involved: isothermal expansion, adiabatic expansion, isothermal compression, and adiabatic compression
Which are the thermodynamic cycle used for refrigeration?
The vapor-compression cycle is used by many refrigeration, air conditioning and other cooling applications and also within heat pump for heating applications There are two heat exchangers, one being the condenser which is hotter and releases heat and the other being the evaporator which is colder and accepts heat
Is Stirling cycle reversible?
The cycle is reversible, meaning that if supplied with mechanical power, it can function as a heat pump for heating or cooling, and even for cryogenic cooling The cycle is defined as a closed regenerative cycle with a gaseous working fluid
What is Carnot cycle in thermodynamics?
: an ideal reversible closed thermodynamic cycle in which the working substance goes through the four successive operations of isothermal expansion to a desired point, adiabatic expansion to a desired point, isothermal compression, and adiabatic compression back to its initial state
What is a thermodynamic process and a thermodynamic cycle?
A process in which a fluid (water, air, ammonia, etc) successively changes state (from a liquid to a gas and back to a liquid) for the purpose of producing or transferring energy
When can a thermodynamic process said to be cyclic?
The process in which the initial and final state is the same is known as a cyclic process It is a sequence of processes that leave the system in the same state in which it started