turbines

1. Assistant Professor: Dr. Muhammad Arif | Email: muhammad.arif@kfueit.edu.pk
CHEN-3111 Fluid Mechanics-II
CHEN-3111 Fluid Mechanics-II
Course Facilitator: Engr. Dr. Muhammad Arif

2. INTRODUCTION
Course Outline:
Flow of Compressible Newtonian Fluids, Flow through porous media; Fluidization and types of fluidized
beds and their use in chemical engineering, Particle and Regime classification, minimum fluidization
and particulate fluidization, entrainment and elutriation, concept of hydrodynamic characteristics of
fluidized beds, bubbling fluidization, turbulent fluidization, slurry bed fluidization. Industrial application
of fluidization. Introduction to non-Newtonian fluids, Flow through packed beds, types of packing,
hydrodynamics of packed column Fluid Motion in the Presence of Solid Particles, Relative motion
between a fluid and a single particle, Effect of presence of other particles and wall on the particle
velocity Turbo-machinery and its classifications. Compressors, their classification, characteristics and
selection. Turbines, their classification and selection. Compressible flow and its application in chemical
engineering, concept of choked flow.
Course: CHEN-3111 Fluid Mechanics-I
Course Objectives:
To impart in-depth knowledge about the selection and design of fluid flow systems in process industry.

3. INTRODUCTION
Books:
1) Holland, F. A. Bragg, R. “Fluid flow for Chemical Engineers”, 2nd Ed., Butterworth
Heinemann. 1995.
2) White, F.M. “Fluid Mechanics”, 7th Ed., McGraw-Hill. 2011.
3) Noel-de-Nevers “Fluid Mechanics for Chemical Engineers” McGraw-Hill, 2004.
4) McCabe Warren L., Smith Julian C., Harriott peter “Unit Operations of Chemical
5) Engineering” 7th Ed., 2010. McGraw-Hill Inc.
6) Coulson J.M., Richardson J.F. “Chemical Engineering” Vol-I, 6th 1999. Butterworth,
Elsevier.
7) Munson B.R., Huebsch W.W., Rothmayer A.P. “Fundamental of Fluid Mechanics” Wiley;
7th Ed., 2012
8) Seppo A. Korpela, “Principles of Turbomachinery”, 2012, Wiley.
Course: CHEN-3111 Fluid Mechanics-I

5. Turbomachine is a power or head generating machine which employs the
dynamic action of a rotating element, the rotor; the action of the rotor changes the
energy level of the continuously flowing fluid through the machine. Turbines,
compressors and fans are all members of this family of machines.

7. Wicket gates are a series
of adjustable vanes
controlling the flow of
water to a reaction
turbine.

12. Types of turbines based on the hydraulic operating range
Low Head Turbines
Hydraulic turbines operating in the head range of fewer than 45 meters are
considered low-head turbines. Kaplan turbine is one of these turbines. If the head is
less than 3 meters, it is considered an ultra-low head.
Medium Head Turbines
The working range for heads of 45 to 250 meters is known as medium heads.
Francis turbines generally operate in such conditions.
High Head Turbines
Turbines with heads higher than 250 meters are known as high-head turbines, Like
the Pelton Turbine.

13. In the figure, you can see
the operating range of
different turbines based on
the changes in head and
flow rate.
https://www.linquip.com/bl
og/types-of-turbines/

14. Types of Turbines Based on Specific Speed
The specific speed of a turbine (denoted by Ns) is defined as the speed of a
turbine with a geometric similarity that can generate a unit of power
under a head unit.
Low Specific Speed Turbine
The values between 1 and 10 are low specific speeds. Impulse turbines operate in
this range. For example, the Pelton turbine usually operates at a specific speed of
about 4.
Medium Specific Speed Turbine
Turbines that operate in the specific speed range of 10 to 100, such as Francis,
have a medium specific speed.
High Specific Speed Turbine
Specific speeds above 100 are considered high values. Kaplan turbine works at a

16. Impulse Turbine
If the turbine wheel is driven by the kinetic energy of the fluid that
strikes the turbine blades through the nozzle or otherwise, the
turbine is known as an impulse turbine.
In these types of turbines, a set of rotating machinery operates at
atmospheric pressure. Impulse turbines are usually suitable for
high head and low flow rates.
Examples: Pelton, Turgo, and Cross-flow turbines are three
types of impulse turbines.
The construction of the Pelton and Turgo turbines is similar.
However, the Cross-flow turbine is a modified type of impulse
turbines that is classified as an impulse turbine due to the
rotation of the runner at atmospheric pressure and not as a

25. Reaction Turbine
If the sum of potential energy and kinetic energy of water which are due to the
pressure and velocity, respectively cause the turbine blades to rotate, the turbine is
classified as a reaction turbine.
In these types of turbines, the entire turbine is immersed in water and changes in
water pressure along with the kinetic energy of the water cause power exchange.
Applications of reaction turbines are usually at lower heads and higher flow rates
than impulse turbines.
Reaction turbines are very diverse. Francis, Kaplan, and Deriaz are among
these turbines.

31. Pelton turbine
A Pelton turbine is a type of impulse turbine in which the flow enters the
wheel tangentially.
The whole set is at atmospheric pressure, the flow with potential
energy and high pressure flows in the Penstock and reaches the
nozzle(s). The nozzle is responsible for converting high-pressure flow
to high-speed flow.
Therefore, the current hits the blades of this turbine, which are in the
shape of a bucket, at high speed and causes the runner to rotate.
These turbines are suitable for high heads (up to 2000 meters) and low flow
rates (4-15 m3/s). They are classified as low specific speed turbines. They
are produced in various sizes and have been used up even to a capacity of
200 MW.

32. Pelton turbine