| From : |
Bruno Ogorelec |
| Date : |
2003-05-22 15:55:25 |
| Subject : |
Re:pulsejet project in school |
Alexander,
If it’s a school project, I would suggest that you approach it as a research project and include a number of other pupils in it.
You pose a problem – if you have a cylindrical can, and two unequal length pipes sticking out, and if you feed flammable gas into it, chances are that pulsating combustion and pulsating gas flows will be established and that the pulsations will generate thrust. What conditions must be satisfied?
Put together what you know about the chemistry of combustion of a simple gas like propane in air, what you know of fluid flows and what you know about acoustics and try to predict conditions under which the thing will pulsate.
At the same time, try to get the engine to pulsate by varying the pipe lengths and the rate of fuel supply. At some point, it will start working as an engine. Compare the successful layout with predictions.
As I said, you don’t need anything fancy – just a steel can and two tube stubs welded to one end. Cut screw thread to the stub ends. Prepare a collection of tubes of various lengths that can simply be screwed onto the stubs. To supply gas to the engine, modify parts of a Bunsen burner. Use kitchen gas igniter for ignition.
Keep the tubes vertical and mount the engine on bathroom scales to measure thrust. Put a ceramic tile underneath to prevent the scales from heat.
Keep the fire extinguisher ready and always wear protective mask. Ear protectors are also a very good idea.
Bruno
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Re:pulsejet project in school
( 2003-05-22 15:55:25)