Jet Pulse DroneTEAM 59-PULS

John Hamburg (PM)Kyle Goetzelmann Michael Godinho Eileen SchweissDavid MorrisMatt Benes

ME -ME -ME -ME - ME -ECE -

Faculty Technical Advisor: Dr. Kanchan Mondal

Executive Summary

 

Pulse jet engines differ from traditional jet engines in that they do not make use of any turbines or

compressors. Instead they rely on inertia of moving gases to achieve their relatively small compression ratios. The

lack of turbines and compressors makes the design of pulse jet engines relatively simplistic, with few or no moving

parts.

The proposed new pulse jet engine will feature a valve less design utilizing rear-facing air intakes. Having the

intakes face the same direction as the exhaust means that any expanding gases that escape through the intakes during

combustion will add to the total thrust produced by the engine. This allows the engine to forgo the use of reed valves

which struggle to hold up to the conditions inside the combustion chamber and end up severely shortening the useful

life of the engine. The engine will achieve greater efficiency through the use of a throttling device which will allow

the engine to use less fuel when performance is not as essential. Research and possibly simulations will be used to

allow the engine to run as smoothly and efficiently as possible. The proposed engine will also utilize temperature

and flow sensors used in conjunction with a telemetry system to provide real time feedback on engine and plane

performance.

The project is expected to be complete by March 31, 2014, allowing for several weeks of testing and tuning

after completion. The total cost of the project is expected to be no more $1,000.00. This cost depends on the prices of

components such as the material cost of stainless steel for the engine body, which is subject to change.

Contents• Overview• Engine Materials Discussion• Subsystem Technical Discussions• Deliverables

OverviewThe design team will design and construct a pulse jet engine that will be fitted to a RC plane constructed by an Aviation Technologies student

How it works• A pulse jet is a simple engine

that operates on a pressure differential• After all combustion gases

exhaust, a low pressure zone is created, which draws in fresh air• This air is mixed with fuel and

then ignited by the existing fireball• This is one “pulse” the cycle

repeats hundreds of time every second to keep a steady thrust

Engine Material• OnlineMetals.com• McMaster-Carr.com• Combination of 304 Stainless Steel tubing and sheet

metal• Thinnest tubing and sheet metal will be chosen to optimize design• Size will be based upon FLUENT analysis

• Coated in 100% 316 Stainless Steel pure pigment

Subsystems• Intake• Fuel System• Ignition• Combustion Chamber• Exhaust/Augmenter• Telemetry

Ignition System• Necessary to get engine started• A spark plug mounted in the front of the combustion

chamber will be utilized

Intake• A reverse style intake will be utilized to maximize the

usefulness of combustion gasses• FLUENT analysis will be used to determine the proper

size and shape of the inlets• The flow of air into the engine is critical to sustaining

combustion

Combustion Chamber• Part of engine where combustion originates• Must cause air and fuel to mix together• Must force expanding gases to travel through the back

of the engine

L. Cottrill. “Original 2D Schematic” Internet: http://grabcad.com/library/valveless-pulse-jet-engine,[11/26/13]

Types of Fuel• Factors• Flash Point• Ease of Ignition

• Auto Ignition• Prevent Spontaneous Combustion

• Internal Energy• Max amount of energy provided

• Chemical Composition• Corrosive property and residue

• Burn Rate and Temperature• Flight time and effect on engine

Types of Fuel (cont.)• Several different Fuels can be used• Design Based on JP-8• Testing will include gasoline, aviation fuels, and different

combinations of Kerosene and Hydrocarbon based fuels• Hydrocarbon based fuels can be easily mixed together

• Static testing will be used to determine which will give max efficiency based on requirements• Corrosive properties of the different mixtures can be

seen through static testing as well

Fuel System

• Non pressurized fuel tank with fuel pump• Different fuel types/mixtures• Easy refueling• Pump gives consistent flow (voltage regulated)• Throttling• Fuel Efficiency

• Fuel Nozzle• Evenly dispersed into the airstream• Upstream of ignition

Exhaust/Augmenter• Can significantly increase the

thrust of the engine without any additional fuel consumption• Proper size and shape must be

determined to maximize thrust while minimizing drag• Fluent Analysis will be used to

determine optimal exhaust design

Telemetry System• Measure Engine Temperature and Airspeed• K-type Thermocouple• Pitot tube airspeed sensor

• Store measured data locally and at ground station• Local SD card• Ground based hard drive

• Transmit live data to ground station• RF transmitter with 1 mile range

• View data in real time using graphical interface• MatLab analysis• Data can be used to monitor engine vitals and performance

Deliverables• FLUENT analyses of intake and exhaust areas• CAD drawings• Engine• Airplane