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= Parts =
 
= Parts =
 
[[Bild:Scaled-dscn9121.jpg|thumb|Overview of the rocket parts]]
 
[[Bild:Scaled-dscn9121.jpg|thumb|Overview of the rocket parts]]
All parts directly participating in the combustion would have to sustain at least 51 bar (vapor pressure of N<sub>2</sub>0 at 20°C) but for reasons of safety i assume 200bar as the minimum.
+
All parts directly participating in the combustion would have to sustain at least 51 bar  
 +
(vapor pressure of N<sub>2</sub>0 at 20°C) but for reasons of safety i assume 200bar as the minimum.
  
 
* [http://en.wikipedia.org/wiki/Pressure_vessel Run Tank]: A light-weight container for the oxydizer capable of sustaining enough pressure
 
* [http://en.wikipedia.org/wiki/Pressure_vessel Run Tank]: A light-weight container for the oxydizer capable of sustaining enough pressure

Version vom 30. Juli 2009, 05:52 Uhr

WTF?

Hybrid rocket propulsion system conceptual overview

Nomen est omen. Salami rocket is about building a hybrid rocket with a gaseous oxydizer (N20) and salami as propellants.


Oxydizer

I chose N2O over O2 because although N2O carries a lot of conjectural inert nitrogen (64%) oxygen is much harder to handle (tank filling, storage & injection). Additionally the nitrogen, though not participating in combustion, raises the fuel erosion rate and cooles the nozzle enough to reuse it many times. Since the alternatives i found are quite expensive, i use the nitrous oxyde of whipped-cream chargers. By the way, never search for "Sahnespender" at google.

Fuel

Salami: High efficency hydrocarbon based fuel ;)

Simulation

Im using RockSim to simulate the flight stability of the rocket. The behaviour of the N20/ hybrid motor is simulated by an external model programmed in C++.

Parts

Overview of the rocket parts

All parts directly participating in the combustion would have to sustain at least 51 bar (vapor pressure of N20 at 20°C) but for reasons of safety i assume 200bar as the minimum.

  • Run Tank: A light-weight container for the oxydizer capable of sustaining enough pressure
  • Throttle Valve: A valve to allow precise regulation of the oxydizer flow from the run tank to the combustion chamber.
  • Injector: Aids in vaporizing the (still) liquid oxydizery.
  • Combustion Chamber: Where the oxydizer/fuel mix burns. Additionally to pressure (same amount as for the run tank) it has to sustain heat.
  • Nozzle: An opening that dramatically accelerates the hot gas escaping the combustion chamber.
  • Ignitor: Preheating the fuel and initializing combustion.
  • Body tube: Enhances airodynamic properties of the rocket and encapsulates the motor.
  • Motor mount: Anchors the motor within the body tube
  • Fins: Enhances airodynamic/stability properties of the rocket.
  • Recovery System (parachute): Enables slow decent after burn-out for safety and reusability
  • Tail camera: It's all about the nice view
  • Altimeter: Measurement concludes the fate of the cat
  • Electric beacon: Transmits a signal to ease finding the landing site.
  • Filling system: Pipework to fill the run tank with nitrous oxyde from whipped cream chargers.

Run Tank

Run tank

Smart Parts C02 aluminium tank for paintball guns with on/off valve.

  • Capacity: 591ml (20 oz)
  • Connector: 1,27cm (1/2")
  • Max Pressure: 200bar

Throttle valve

Throttle valve

An adjustable throttle valve ([1]) intended for use in hydraulics.

  • Connector: 1,27cm (1/2")
  • Flow rate: 45 l/min
  • Working pressure: 350 bar



Injector

Injector

SKR-54UC

  • Diameter: 54mm




Combustion Chamber

Combustion chamber

C02 aluminium tank for paintball guns without on/off valve.

  • Capacity: 255ml (9 oz)
  • Connector: 1,27cm (1/2")
  • Max Pressure: 200bar

Nozzle

Nozzle

SKR-54NZL graphite nozzle

  • Diameter: 54mm




Ignitor

None selected yet.

Body tube

Body tube

Cardboard tube, intended for postal delivery.

  • Dimension: 1000 x 140 x 3 mm





Motor mount & Fins

Motor mount and fins

Wooden centering rings and perspex fins, precisely milled with a CNC machine.




Recover System

None specified/selected yet.

Testing

After a few backyard tests with a rather improvised device, we tested the actual motor at Lindabrunn. Special thanks to kyrah and marius for support, pyromantic inspiration and fuel sponsoring.

Links