Perfect Gas process

Question 1

Perfect Gas process

Answer 1

Pv= mRT
Q= w + DetlaU
Detla H= m x Cp x Delta T

Question 2

Constant Volume (Rigid- Cylinder)

Answer 2

V= c
w=0
Q= Delta U= M x Cv x Delta T
- P1/ P2 = T1/T2

Question 3

Constant Pressure (Isobaric)

Answer 3

P= c
w= P(V2 - V1) / (h2 - h1) - DeltaU/ Q- Delta U
Q= m x Cp x DeltaT/ (h2-h1)
V1/V2 = T1/T2

Question 4

Constant Temperature (Isothermal)

Answer 4

T= c / PV=c
w= c x ln v2/v1 / c x ln p1/p2
Q= w Delta U= 0 Deltah= 0
T1= T2
P1V1 = P2V2

Question 5

Adiapatic/ Isentropic (Thermally isolated)

Answer 5

PV^ g = c Q= 0
w= -DetlaU = m x Cv x (T1- T2) = P1V1-P2V2/ g -1
P1/P2 = (V2/V2)^g
T1/T2 = (p2/p1)^ g-1/g

Question 6

Polytropic:

Answer 6

PV^n= c
w= P1V1-P2V2/ n - 1 = mR(T1-T2)/n - 1
Q= w( g-n / g-1)
n>1
P1V1^n = P2V2^n

Question 7

Entropy:

Answer 7

Delta S= m x Cp x Ln T2/T1 + mR x Ln P1/P2
Or
M x Cv x Ln T2/T2 + mR x ln V2/V1

Question 8

To solve:

Answer 8

1) Get Cv , Cp, g, R
2) Get m
3) Get P, V, T for each state
4) Get w, Q for each state
5) Draw pv and ts diagram