Lecture 18 Flashcards
What is thrust?
Forward-directed force from a
rearward acceleration of a mass
of air or fluid
What are the two methods for producing thrust?*
Aerodynamic Action
Jet Reaction Engines
Describe aerodynamic action
Utilizes propellers
Lift produced along a horizontal plane
Large mass of air through small change in velocity
What was the first item to demonstrate jet propulsion?
When?
Who created it?
“Aeolipile”
First century A.D.
Heron of Alexandria in Egypt
When did the Chinese begin using rockets as weapons?
1232
When was the first true gas turbine engine designed?
Who designed it?
What was the problem with it?
1872
Dr. F. Stolze
This engine never ran under its own power
When was the first flight of a gas turbine jet?
What was the jet called?
What company flew it?
1939
HE178
Ernst Heinkel Aircraft
When was the first successful turbojet airplane designed?
What was it called?
Who designed it?
What happened to the design in 1982?
1941
Gloster Meteor
Sir Frank Whittle
Engine prototype shipped to General Electric in the United States
What was the world’s first operational jet fighter?
When was it developed?
Messerschmitt Me 262
1942
How does Bernoulli’s Principle apply to jet engines?*
Jet engines use divergent and convergent ducts to speed up and slow down the inlet air
Bernoulli’s Principle causes increase/decrease in velocity, pressure, and temperature
Compare the Brayton Cycle and the Otto Cycle*
In both the Brayton cycle and the Otto cycle there is intake, compression, combustion, exhaust
However, in the Otto cycle, each cylinder undergoes each of those events whereas in the Brayton cycle those events are always occurring simultaneously but in different parts of the engine
What happens in a convergent duct with airflow at subsonic speeds?*
Velocity increases
Pressure and density decrease
What happens in a divergent duct with airflow at subsonic speeds?*
Velocity decreases
Pressure and temperature increase
