[Physics Class Notes] on Cyclic Process Pdf for Exam

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 is represented by 1 and 2 in a particular process of quasistatic that takes a given system from state 1 to state 2. We can say that the heat exchange between the system and surroundings can be given as đrQ1→2 in it.

 

We ask whether it matters if this quantity is positive or negative. Select a second path that 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 that is closed, the system returns to its original thermodynamic state of pressure and temperature. The quantities or we can say the path quantities such as work and heat are process-dependent. For a full and 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 in the system over the cycle. We denote it as E_in which might be the heat and work that input during the cycle and E_out 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 Q_in as positive and Q_out as negative. 

 

What is the Cyclic Process?

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

 

Work Done in Cyclic Process

 

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The power of thermodynamic cycles is said to be 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 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.