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Every so often, my hobby and my day job intersect.
I was doing some research for a project and came across a paper by the Air Force Research Lab from 2001 about development work on a pulse detonation engine (PDE). Yes, that's an outgrowth of the German V1 "buzz bomb" pulse jet engines from WWII.
In this case, AFRL was trying to build a very low cost engine for disposable use, such as in drones or missiles. They tried to adapt an existing automotive cylinder head as the basis for this PDE demo. The cylinder head selected was none other that one from a Quad 4. This demo engine had four tubes, each firing at up to 100 times a second. They succeeded in a successful firing on their first attempt, using propane and air. Later tests used hydrogen and air. Yes, the stock spark plug was used to fire the mixture.
Every so often, my hobby and my day job intersect.
I was doing some research for a project and came across a paper by the Air Force Research Lab from 2001 about development work on a pulse detonation engine (PDE). Yes, that's an outgrowth of the German V1 "buzz bomb" pulse jet engines from WWII.
In this case, AFRL was trying to build a very low cost engine for disposable use, such as in drones or missiles. They tried to adapt an existing automotive cylinder head as the basis for this PDE demo. The cylinder head selected was none other that one from a Quad 4. This demo engine had four tubes, each firing at up to 100 times a second. They succeeded in a successful firing on their first attempt, using propane and air. Later tests used hydrogen and air. Yes, the stock spark plug was used to fire the mixture.
The spark plug is in the middle, is that considered a "Hemi"?
The spark plug is in the middle, is that considered a "Hemi"?
Spark plug in the middle does not make it a Hemi. Hemi stands for hemispherical combustion chamber. In this case, that's tough to do with four valves. It's actually more of a pent roof chamber, since the intake valve stems are parallel, as are the exhaust valve stems. To be a true hemispherical chamber, all valve stems would need to be on a radius from the center of the chamber. That's possible but not practical with four valves.
Every so often, my hobby and my day job intersect.
I was doing some research for a project and came across a paper by the Air Force Research Lab from 2001 about development work on a pulse detonation engine (PDE). Yes, that's an outgrowth of the German V1 "buzz bomb" pulse jet engines from WWII.
In this case, AFRL was trying to build a very low cost engine for disposable use, such as in drones or missiles. They tried to adapt an existing automotive cylinder head as the basis for this PDE demo. The cylinder head selected was none other that one from a Quad 4. This demo engine had four tubes, each firing at up to 100 times a second. They succeeded in a successful firing on their first attempt, using propane and air. Later tests used hydrogen and air. Yes, the stock spark plug was used to fire the mixture.
