1. “PULSEJET–ROTOR ENGINE”
Report of the 8th Semester Project Work
SUBMITTED BY:
NAVEEN. S (3VC09ME060)
K.V.MANJUNATHA (3VC10ME037)
SUNDEEP KUMAR.T (3VC09ME102)
RAVI TEJ REDDY.H (3VC09ME085)
Under the guidance of
MANJUNATH SWAMY
Assistant Professor
Department of Mechanical Engineering

2. Introduction
 A pulse jet engine (or pulsejet) is a type of jet engine in
which combustion occurs in pulses.
 Pulsejet engines are characterized by simplicity, low cost
of construction, high noise levels and thrust-to-weight
ratio is excellent.
 They are mechanically very simple and have very less
moving parts.
 Theoretically the pulsejet engine has higher efficiency
than the normal jet engine.
 Another key factor is that, as the combustion occurs in
pulses, constant combustion of fuel is achieved.

3. Literature Survey
• The experiments conducted by THE HILLER AIRCRAFT
CORPORATION is specifically important to the current study.
• Hiller worked on scaling down the valveless pulsejets. The
smallest pulsejet they were able to operate, had a
combustion chamber of dia 19cm & an overall length of
31cm
• This configuration was quite temperamental & hard to
operate on consistent basis.
• It operated more as pulsed rocket rather than a pulsed jet.
• However this study was very beneficial in having a base line
with which to compare.

4. • MICHAEL SCHOEN’s research was directed
towards the miniaturization of valveless
pulsejets.
• His efforts were to understand the physical
effects on engine performance subject to the
changes in jet geometry.
• ADAM KIKER’s work focused on the development
of micro-scale pulsejets.
• He was able to design and operate a record 8cm
long, air breathing, hydrogen fueled pulsejet.

5. • ODON contributed for the development of 5cm
pulsejet by the application of platinum coating on
the combustion chamber walls.
• Odon was able to run it in both valved and valve
less configurations.
• Odon made a formulation of an analytical model
to predict the operating frequency of any valve
less pulsejet.
• DANIEL PAXON at NASA Glenn research center used
a 50 cm hobby scale pulsejet similar to that used
by Odon.

6. Fig: 8cm & 5cm
pulsejets
Fig: 50cm
pulsejet

7.  Our pulsejet resembles to the pulsejet of Daniel Paxon but
differs in the dimensions of tail pipe.
 Out of various types of pulsejets, the pulsejet we used fall
under the class of the SIDEWINDERS.

8. Reasons for developing this idea
Efficiency of pulsejet is high compared to IC engines.
It has simple and low cost construction and can be
scaled to any size.
They have very less moving parts, and hence
mechanical efficiency is high.
So the basic concept of “pulse jet rotary engine” is
to combine the effectiveness of pulse jet with
purpose and practicality of IC engine.

9. Working:
 The LENOIR CYCLE is an idealized thermodynamic
cycle often used to model a pulsejet engine.
 In this cycle, an ideal gas undergoes
1-2: Constant volume heat addition
2-3: Isentropic expansion
3-1: Constant pressure heat rejection.
 The expansion process is isentropic and hence
involves no heat interaction. Energy is absorbed as
heat during the isochoric heating and rejected as
work during the isentropic expansion. Waste heat
is rejected during the isobaric cooling.

10. Lenoir cycle:

11. Working:

12. The working is based on KADENACY EFFECT
 The expanding gas out of the engine all the way until the
pressure in the chamber falls below atmospheric. The
opposite thing happens in the next part of the cycle, when
the outside air pushes its way in to fill the vacuum. The
combined momentum of the gases rushing in through the
two opposed ports causes the chamber briefly to be
pressurized above atmospheric before ignition.
 Thus there is an oscillation of pressure in the engine
caused by inertia. The gases involved in the process are
stretched and compressed between the inside and outside
pressures like an elastic medium. This kind of effect is
called the KADENACY EFFECT.

13. Specifications of Pulsejet

14. Construction
As shown below, 3 pulse jets are arranged in a
circular fashion (120 degrees apart)
Due to the impulse of pulse output from pulsejets
tangential force is impacted on cups. Due to this
tangential force couple is formed thus rotary motion is
obtained.
Thrust from the pulses are thus converted to
rotary motion.

17. Spark plug connected to ignition coil

18. Pulse Jet Testing

19. Materials used
 Stainless Steel (commercial name-SS 304) for
pulsejet body.
 1 cm copper tubes for fuel supply.
 Mild steel cover plates.
 20 mm hollow MS shaft.
 22 mm Bosch bearings with its housing.
 Two wheeler sparkplug.
 1” square pipes for engine mount.

20. Engine fabrication
 Stainless steel tubes of 1”,12 and 8 mm dia are
cut according to requirement and welded.
 Blades are shaped and modified based on
requirement. They are mounted on a circular
frame which in turn welded onto bearings.

21. Fuel Used
 Liquid petroleum gas (C3H8) is used as
pulsejet fuel but pulse jets works on
variety of fuels such as gasoline,
kerosene, liquid propane , natural gas
etc..,

22. Plan of action proposed
1.Final assembly
All the sub-assembly parts are assembled
and engine will be enclosed by cover
plates.
2.Testing
The pulsejet is tested for its functionality.

23. Progress done in the project
so far
 As per the plan of action we have successfully
developed and fabricated a complete working
model of pulse jet.
 This helped us understand the fabrication
difficulties and the design considerations that
we will have to make in the final model. Further
we tested this model by considering various
aspects of design as to develop more efficient
final model.

24. Results
 By directing the output thrust from 3 pulsejets on to the
rotary blades, it is possible to convert the thrust energy to
rotary motion.
 As 3 pulsejets have to be synchronized to have optimum
power, computer controlled fuel supply is required.
 This also requires cooling system to cool down the pulsejets
since its working temperature is generally well above 800oc.
 It is simple and attractive, but it also has its disadvantages.
The promise of pulsejets on its own, outside a turbojet, is
less significant.
 The average pressure in working cycle is low.

25. Conclusion
 As it is generally known that pulsejets are more efficient
than any other jet engines, they can be used to derive
power from the fuel more efficiently.
 Thus it is possible to replace the current combustion
chamber of an IC engine to a pulsejets because of design
simplicity, no moving parts and power to weight ratio.
 Finally, a simple light weight pulsejet seems much
appropriate for both flying and general purpose engines.

26. References
 "A historical review of valve less pulsejet"
designs by Bruno Ogorelec
 http://www.frenchgeek.com/pulsejet.php - A
detailed guide documenting all the steps
required to build one's own Pulsejet.
 PETA (Pulse-Ejector-Thrust-Augmentors) article
 www.becktechnologies.com
 www.xjet/pulsejet-argusV1.com
 Aviastar information on Hiller rotor-tips
 “Dave Brill” has give us a lot of information
about the pulsejet theory

27. “
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Thank you all!