Project
Steam Rocket
Construction
- This rocket was constructed out of 2" type L copper pipe. The lower section contained the water that would be heated into steam. The middle section contained nitrogen and a release mechanism to deploy the parachute in the top section. The nose cone was a turned piece of wood which was purchased from an outside source. A portable generator supplied 120 volts to a immersion heating element in the lower section which turned the water to high pressure, high temperature steam. Attached to the bottom of the rocket was a 1/2" dielectric union with a disc of .002 brass shim stock inserted in the union. Tests proved that this thickness of shim stock would rupture at 250 PSI in a 1/2" union. Also tested was .003 brass shim stock which ruptured at 500 PSI and .004 brass shim stock which ruptured at 1000 PSI. It took about one hour to bring the water temperature and pressure up to the point where it would blow the rupture disc.
Pros
- Steam is an inexpensive, reliable propellent.
Cons
- Materials needed to contain high temperature steam are going to be heavy in nature.
- A substantial amount of energy is required to phase water into high pressure steam.
- There is no way of knowing when the rupture disc will burst. However, a small explosive charge could be installed on the downside of the disc to force a rupture.
- Threaded fittings fit progressively poorer every time the engine is heated and cooled.
- If a leak develops while the engine is heating it will not reach enough pressure to burst the rupture disc and will need to be shut down. It may take over an hour for the engine casing to cool down enough to be handled.
- Thrust duration is relatively short.
Pictures
Video
CAD Drawings
