A steam injector, invented by Henry Griffard in 1858, is a device that uses live or exhaust steam to deliver cold water to a boiler against its own pressure, eliminating the need for mechanical pumps. It operates on the principles of thermodynamics, utilizing the venturi effect to convert steam pressure into velocity before condensing the steam and increasing water pressure. While it offers advantages like low cost, high thermal efficiency, and energy efficiency, it has limitations regarding pumping efficiency and operating conditions.

1. STEAM
INJECTOR
Applied
Thermodynamics-1
By:- Parth Dhar

2. CONTENTS
 What is Steam Injector?
 Components & Construction
 Principal & Working
 Advantages
 Disadvantages
 Applications
 Visual Representation

3. What is a Steam
Injector?
 Invented in 1858 by Henry Griffard.
 Is used to deliver cold water to a boiler against its own pressure
using its own live or exhaust steam, replacing any mechanical pump.
 It works on the principal of thermodynamics and pressure.

4. Components and
Construction
 Boiler
 Connecting Tube
 Converging-diverging steam Cone
 Water Reservoir
 Combining Cone
 Overflow Chamber
 Delivery Cone
This Photo by Unknown Author is licensed under CC BY-SA

5. Principal & Working
1. It uses the Venturi effect of converging-diverging nozzle on a steam jet to convert
pressure energy of the steam to velocity.
2. Now it leads to reduction of pressure below atmosphere which enables it to entrain a
fluid.
3. After passing through the convergent "combining cone", the mixed fluid is fully
condensed releasing the latent of the steam which imparts extra velocity to the water.
4. After this ,mixture is allowed to pass through a divergent cone which slows jet and
converts kinetic energy to static pressure energy which is more than the pressure inside
the boiler.

6. This Photo by Unknown Author is licensed under CC BY-SA

7. Low initial
cost
Simplicity
Compact
ness
Thermal
Efficiency
is very high
Eliminates
the usage
of pump.
Energy
efficient
Wide
Operating
Range
Less
Wastage of
Resources
Low
Noise
Level
Advantages

8. Disadvantages
Pumping
efficiency is
low.
Irregularity of
operation under
extreme variation
in steam
pressure.
It cannot
force very
hot water.
Not suitable for
water below 4
degree Celsius.

9. Applications
Traditionally in steam locomotives.
In thermal power
stations
Oil & Gas
industry
Aspirator
s
Nuclear power
plants
Water
eductors
Stem jet
Cooling
system

10. This Photo by Unknown Author is licensed under CC BY-SA

11. Information Source
Sources
https://www.sciencedirect.com/science/article/pii/
https://www.scientificamerican.com/article/applications-
of-the-giffard-injecto/
https://en.wikipedia.org/wiki/Injector
https://www.youtube.com/watch?v=4wsiXPgfdlI

12. Thank You