Cyclic Process

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Opening the discussion with the lines that consider cyclic processes which constitute a very strong and powerful tool in final deductions based on the Second Law. the Consideration of two points in configuration space that are infinitesimally close to one another. As it is represented by 1 and 2 in Choose a particular process of quasistatic that takes a given system from state 1 to state 2. That is we can say that the heat exchange which is between the system and surroundings be given as đrQ1→2 in it.


We ask whether it matters if this quantity is positive or negative . Select a second path which is irreversible that affects the same 1 → 2 change and that literally involves a heat exchange điQ1→2. This path latter is dashed on the diagram which is shown above being a process which is irreversible the path which lies outside the phase space appropriate to quasi static processes. 

By the First Law which is given as đrQ1→2 = dE1→2 – đrW1→2, and điQ1→2 = dE1→2 – điW1→2.

Cyclic Process in Thermodynamics

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In this whole process of passing through a cycle that is working fluid that is the system may convert heat from a warm source into useful work and even dispose of the remaining heat to a sink of cold. Which is thereby acting as a heat engine. The basic or major conversely that  the cycle may be reversed and use work to move heat from a source which is cold and transfer it to a warm sink thereby acting as a heat pump. At each and every single point in the cycle we can assume that the system is in thermodynamic equilibrium. So here we can conclude that the cycle is reversible, that is its entropy change is zero as entropy is a state function.

During a cycle which is closed, the return system to its original thermodynamic state of pressure and temperature. The quantities Process or we can say the path quantities such as work and heat are process dependent. For a full and a proper cycle for which the system returns to its initial state the first law of thermodynamics applies the following: 

The above clearly states that there is no energy change of the system over the cycle. We denote it as  Ein which might be the heat and work that input during the cycle and Eout would be the work and heat output during the cycle. The first law which is of thermodynamics also dictates that the net heat input is equal to the network that is output over a cycle. We can account for heat denoted as Qin as positive and Qout as negative. 

What is Cyclic Process?

Two classes which are of primary nature of thermodynamic cycles are very powerful cycles and heat can pump the cycles. The cycles of power are cycles which convert some amount of heat input into a work mechanical output, while the pump of heat cycles transfer heat from low to high temperatures by using work which is mechanical as the input. 

Work Done in Cyclic Process

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The power of Thermodynamic cycles are said as the basis for the operation of heat engines which can truly supply most of the world's power of electricity and run the vast majority of motor vehicles. The cycle of Power can be organized into two categories: that are the ideal and the real cycles. The encountered cycles which are in real world devices that are the real cycles are difficult to analyze because of the presence of effect which is complicating friction. And the absence of sufficient time which is given basically for the establishment of conditions of equilibrium. 

For the analysis purpose and design, and at times the model which is idealized ideal cycles are created. Here we can say that the power cycles can also be divided directly according to the type of heat engine they seek to model. The most common cycles which are used to model combustion which are internal engines are the cycle Otto which generally models gasoline engines. And the cycle which is of the Diesel which has the models diesel engines. The Cycles that external model  combustion engines include the Brayton cycle, which models tribunals of gas, the cycle of Rankine which when models steam turbines the cycle which is Stirling which models hot air engines and at times the Ericsson cycle which also models hot air engines.

FAQ (Frequently Asked Questions)

Q1. What is the Work Which is Done in a Cyclic Process?

Ans: The net work which is involved in a process which is cyclic is the area enclosed in letter  P-V. If the cycle goes in a direction which is clockwise then the system does work. If the cycle goes in a direction which is anticlockwise then the work which is done on the system every cycle. An example of such a system is an air condition or the refrigerator.

Q2. What is the Process of Thermodynamic and a Cyclic Process?

Ans: In a cyclic process we have seen that the system starts and returns to the same state of thermodynamic. If the cycle goes in a direction which is clockwise then the system does work.  A process which cyclic is the underlying principle for an engine. If the cycle goes in a direction which is counterclockwise, work is done on the system every cycle.

Q3. Is the Process a Cyclic and Reversible Process?

Ans: All the processes which are cyclic are reversible but not all reversible processes are cyclic. In a process which is cyclic the system needs to follow the complete cycle to reach the initial state. Thus, the cycles which are reversible are those in which the system can follow the exact same path backwards.

Q4. What is a Cyclic Process Which is Zero?

Ans: The change which is almost in every energy in a cyclic process is zero, since the final and initial states are the same. The work which is done and the quantity of heat gained in such a process are said the same therefore that with opposite signs that is R = –Q.