2. OBJECTIVES:
ME8595-THERMAL ENGINEERING II
To apply the thermodynamic concepts for
Nozzles, Boilers, Turbines, and Refrigeration &
Air Conditioning Systems.
To understand the concept of utilizing
residual heat in thermal systems.
3. COURSE OUTCOMES:
ME8595 -THERMAL ENGINEERING II
Upon the completion of this course the students will be
able to
CO1-Solve problems in Steam Nozzle
CO2-Explain the functioning and features of different
types of Boilers and auxiliaries and calculate performance
parameters.
CO3-Explain the flow in steam turbines, draw velocity
diagrams for steam turbines and solve problems.
CO4-Summarize the concept of Cogeneration, Working
features of Heat pumps and Heat exchangers
CO5-Solve problems using refrigerant table / charts and
psychometric charts
4. COURSE OUTCOMES:
C 351.1
Students will be able to design the steam nozzle
and evaluate the velocity of steam at the exit using
steam table and Mollier chart.
C 351.2
Students will be able to dissect the boiler and
interpret the working of boiler mountings and
accessories and to evaluate the performance and
heat balance of the boiler.
5. C 351.3
Students will be able to design steam turbines and
construct velocity triangles illustrating blade
profiles of steam turbines.
C 351.4
Students will be able to design and evaluate the
power and heat generated by cogeneration power
plant and to interpret the working of heat pipe,
heat pump and heat exchangers.
6. C 351.5
Students will be able to construct vapour
compression and vapor absorption refrigeration
systems and to predict the performance of
various refrigeration and air conditioning
systems using refrigeration table and
psychometric chart.
C 351.6
Students will able to solve problems using steam
tables and mollier charts
7. ME8595- THERMAL ENGINEERING – II
Syllabus 2017 Regulation
UNIT I
STEAM NOZZLE 9
Types and Shapes of nozzles, Flow of steam
through nozzles, Critical pressure ratio, Variation
of mass flow rate with pressure ratio. Effect of
friction. Metastable flow.
8. UNIT II
BOILERS 9
Types and comparison. Mountings and
Accessories. Fuels – Solid, Liquid and Gas.
Performance calculations, Boiler trial.
9. UNIT III
STEAM TURBINES 9
Types, Impulse and reaction principles, Velocity
diagrams, Work done and efficiency – optimal
operating conditions. Multi-staging,
compounding and governing.
10. UNIT IV
COGENERATION AND RESIDUAL HEAT
RECOVERY
Cogeneration Principles, Cycle Analysis,
Applications, Source and utilization of residual
heat. Heat pipes, Heat pumps, Recuperative and
Regenerative heat exchangers. Economic
Aspects.
11. UNIT V
REFRIGERATION AND AIR – CONDITIONING 9
Vapour compression refrigeration cycle, Effect of
Superheat and Sub-cooling, Performance
calculations, Working principle of air cycle, vapour
absorption system, and Thermoelectric
refrigeration. Air conditioning systems, concept of
RSHF, GSHF and ESHF, Cooling load calculations.
Cooling towers – concept and types.
12. STEAM NOZZLES
• The nozzle was developed (independently)
by German engineer and inventor Ernst
Körting in 1878 and Swedish inventor
Gustaf de Laval in 1888 for
use on a steam turbine
13. • A nozzle is a passage of varying cross-
sectional area in which the potential
energy of the steam is converted into
kinetic energy. The increase of velocity of
the steam jet at the exit of the nozzle is
obtained due to decrease in enthalpy (total
heat content) of the steam.
14. • Function
• To convert enthalpy (total heat) energy
into kinetic energy.
• When the steam flows through a suitably
shaped nozzle from zone of high pressure
to one at low pressure, its velocity and
specific volume both will increase.
15.
16. Steam Nozzle
The nozzle, attached to the
casing of the turbine. The
steam enters the nozzle at a
high pressure and a
relatively low velocity. Due
to nozzle action steam
velocity increases at the
cost of pressure and
temperature.
17.
18.
19. Types of Nozzle
• There are three types of nozzles
1.Convergent nozzle
2.Divergent nozzle
3.Convergent-divergent nozzle
20.
21. Convergent Nozzle
• In a convergent nozzle, the cross
sectional area decreases
continuously from its entrance to exit.
• It is used in a case where the back pressure is equal to
or greater than the critical pressure ratio.
21
22. Divergent Nozzle
• The cross sectional area of divergent nozzle increases
continuously from its entrance to exit.
• It is used in a case where the back pressure is less than
the critical pressure ratio.
22
23.
24.
25. Convergent-Divergent Nozzle
• In this condition, the cross sectional area first decreases
from its entrance to the throat and then again increases
from throat to the exit.
• This case is used in the case where the back pressure is
less than the critical pressure. Also, in present day
application, it is widely used in many types of steam
turbines.
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