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Project Description
The goal of this project is to design, build, test and optimize a very small
scale turbojet engine. A gas turbine engine has the ability to produce a
large amount of power relative to its weight, one reason why turbojets and
turbofans are the most common form of aircraft propulsion today. If a gas
turbine were made sufficiently small, say, the size of a rechargable power tool
battery, it might be used to efficiently power portable devices such as laptop
computers at a tremendous savings in weight. There are significant
challenges involved in building a small scale gas turbine, such as
 | Igniting and sustaining a flame is difficult at small scales. As the size
of the combustion chamber decreases, the walls of the chamber draw heat away
from the flame more quickly than than it can be produced by the burning of
the fuel. You can demonstrate this phenomonon by trying to get a flame to
pass through a piece of metal window screen held horizontally over a
lighter. You will observe that the flame stops at the plane of the
screen; the wire in the screen dissipates the heat of the flame, preventing
it from passing through. This effect was used with great success in
the creation of safety lamps for miners. |
| Keeping moving parts cool is also difficult at small scales. All parts in
and around the combution chamber become very hot as the turbine operates;
any oils used for lubrication are quickly burned off. Bearing life
tends to be short under these circumstances. |
| Precise fabrication of small-scale parts is always a challenge! The
microturbine runs at 40-70,000 rpm; all rotating parts must be balanced to
avoid catastrophe. |
As an initial effort students at Rowan are in the process of building and
benchmarking a small, RC airplane scale turbojet engine based on the book
"Blah Blah" by Kurt Schreckling. Follow the links at left to see
pictures and movies of the engine in action.
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