Thermodynamic process and open & closed system work and heat transfer in each process:
So importantly 5 processes.
1)Isothermal Process
2)Isobaric Process
3)Isochoric Process
4)Isentropic Process
5)Polytropic Process
And,
A)Closed System work.(given in bellow figure )
B)Open System work.(given in bellow figure)
C)Heat transfer during each process.
ISOTHERMAL PROCESS:
In isothermal process temperature remains constent during the process.
P1×V1 = P2×V2.
Isothermal process is very slow process.
*In isothermal process open system work, closed system work and heat transfer are equal. And its formula is given below.
**open system work = closed system=Heat Transfer for isothermal process = P1V1×ln(V2/V1) = P2V2×ln(P1/P2)=mRT×ln(V2/V1).
ISOBARIC PROCESS:
In isobaric process pressure of the system remains constent.
*V1/T1 = V2/T2
This process is generally used for heat addition
Example.
1)Brayton cycle.
2)Rankin cycle.
3)diesel cycle.
4)Duel Cycle.
*Open system work = 0.
*Closed system work = P×(V2-V1)
*Heat transfer = m×Cp×(T2-T1)
Here Cp = specific heat at constent pressure.
m-mass.
T-Temperature.
ISOCHORIC PROCESS:
During the process volume of the system remains constent.
*P1/T1 = P2/T2
*Closed system work = 0
*Open system work = V×(P1-P2).
*Heat transfer = m×Cv×(T2-T1)
ISENTROPIC PROCESS:
Reversible Adiabatic process is called isentropic process.
P×V^r = P×V^r.
Here r = Cp/Cv.
Open system work = r×(W closed).
Heat transfer =0.
POLYTROPIC PROCESS:
P1×V1^n = P2×V2^n.
Closed system work=[(P1V1-P2V2)/(n-1)]
Open system work = n×(W closed )
Heat transfer = [{(r-n)/(r-1)}×(W closed)]
polytropic coefficient (n) ranges from -infinite to + infinite.
Practical value of n = 1 to r.
r is specific heat ratio.
Value of n for above processes is given in below figure.
It is very important question to identify the process of given curves.
So we are going to simplify this concept also.
Questions regarding this topic will uploaded in important questions POST.
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