Thermodynamics II course taught at air university Islamabad by Sijal Ahmed Memon.

1. Thermodynamics II

2. LECTURE 1
INTRODUCTION

3. Energy
• Kinetic Energy is found in movement
• GRAVITATIONAL
• CHEMICAL
• NUCLEAR
• ELASTIC
• MOTION
• THERMAL ENERGY AND TEMPERATURE
• Electric

4. Energy in thermodynamics
• Heat, Work and Internal energy (1st Law of thermodynamics)
• Close (heat and work) and open system (mass, heat and work)
For open system, add flow
work, h = u + pv

5. Two Phase System

6. Steam Tables
• Subcooled, saturated and
superheated.
• At T = 220 oC, specific volume of
liquid = 0.001194 m3/Kg and
specific volume of sat vapour =
0.086094 m3/Kg.
• At T = 220 oC and x (quality) =
0.325, specific volume:
v = vf + x vfg = 0.001190 + 0.325 *
0.086094 = 0.02917
• Other variables : v, u, h, s

7. Interpolation for Intermediate Properties
• You may need double interpolation
Slope of line

8. Super Heated Table
• At 75 oC, find entropy s. From table
Temperature Entropy S
50 (X1) 8.1488 (Y1)
75 (X) Y = ?
100 (X2) 8.1741 (Y2)
𝑆𝑙𝑜𝑝𝑒 =
𝑌2 − 𝑌1
𝑋2 − 𝑋1
=
8.1741 − 8.1488
100 − 50
= 0.000506
Y= 𝑌1 + 𝑆𝑙𝑜𝑝𝑒 × 𝑋 − 𝑋1
Y= 8.1488 + 0.000506 × 75 − 50 =8.16145
𝑠𝑜 𝑎𝑡 𝑡𝑒𝑚𝑝𝑟𝑎𝑡𝑢𝑟𝑒, 𝑇 = 75 𝑜 𝐶, 𝐸𝑛𝑡𝑜𝑝𝑦 𝑆 = 8.16145
𝑘𝐽
𝑘𝑔. 𝐾

9. Heat Engine and Second Law of Thermodynamics

10. Second Law of Thermodynamics
• Kelvin Planck Statement

11. Second Law of Thermodynamics
• Clausius statement

12. Entropy
• Disorder of system
• Friction, heat transfer and non equilibrium
process
PV and TS diagrams?

13. Work done during process or cycle
Polytypic process
What about the adiabatic process?

14. Work done during process or cycle
Isothermal process

15. Some Important Formulae
PV n= constant
M= 28.97 g/mol,
therefore Ra =
0.287 kJ/kg.K
𝑄 = 𝑚𝐶 𝑝∆𝑇
𝑄 = 𝑚𝐶𝑣∆𝑇

16. Extra