| Process Exponent n | Isothermal & ideal gas 1 | Adiabatic & ideal gas k = C P /C V |
|---|
Which one is the correct equation for work done during the polytropic process of ideal gases where n polytropic index?
γ>n>1
.
What is the boundary work for a polytropic process?
For an ideal gas, P1 V1 is just nRT1 and P2 V2 is nRT2. The result is that the boundary work is
n times R times the change in temperature divided by the quantity 1 minus δ.
What is the equation for polytropic process?
A polytropic process is one where the pressure and volume of a system are related by the equation
PV
n
= C
. Where P represents the pressure, V represents the volume, n represents the polytropic index, and C is a constant.
Is a polytropic process reversible?
Polytropic processes are
internally reversible
. Some examples are vapors and perfect gases in many non-flow processes, such as: n=0, results in P=constant i.e. isobaric process.
What is a polytropic process used for?
The term “polytropic” was originally coined to describe
any reversible process on any open or closed system of gas or vapor which involves both heat and work transfer
, such that a specified combination of properties were maintained constant throughout the process.
Are all processes polytropic?
No, all thermodynamic processes are not polytropic
. As an example, consider a real engine cycle. Any undergraduate engineering thermodynamics text should have a plot showing the true P-V diagram.
Is Polytropic process ideal gas?
| Process Exponent n | Isothermal & ideal gas 1 | Adiabatic & ideal gas k = C P /C V |
|---|
When work is done on the system?
If work is done on the system,
its sign is positive
. If work is done by the system, its sign is negative. Thus, the energy entering the elephant’s front legs has a positive sign. The work the elephant does on the performer has a negative sign.
How do you calculate boundary work done?
Boundary work is evaluated by
integrating the force F multiplied by the incremental distance moved dx between an initial state (1) to a final state (2)
. We normally deal with a piston-cylinder device, thus the force can be replaced by the piston area A multiplied by the pressure P, allowing us to replace A.
Is isothermal process a polytropic process?
TL;DR: Isothermal process are
a subset of the polytropic
. Polytropic encompass all other common processes and more. standard notation implying C is a constant, P the pressure and V the volume.
What is the value of n in Polytropic process?
The value of n can vary from
zero to infinity
. n=0 for an isobaric process, in which the pressure of the system stays constant: ΔP = 0. n= infinity for an isochoric process, when volume stays constant i.e., ΔV = 0.
What is the formula of work done in adiabatic process?
The work done by the mixture during the compression is
W=∫V2V1pdV
. With the adiabatic condition of Equation 3.7. 14, we may write p as K/Vγ, where K=p1Vγ1=p2Vγ2.
What is non quasi static process?
In a non-quasi-static process,
the states between A and B are not known, and hence no path can be drawn
. It may follow the dashed line as shown in the figure or take a very different path.
