Rockets and how they work By Jan-Erik Rønningen Norwegian Rocket Technology [ contact@rocketconsult.no ] [ www.rocketconsult.no ] Version: 1.30 2008

Contents Rocket history Rocket Principle Fundamental Rocket Elements The Solid Propellant Rocket The Liquid Propellant Rocket The Hybrid Rocket Motor

Rocket History 1 The Chinese is claimed by many to be the inventor of the black powder (about 200 B.C) and thus the rockets Newer findings indicate that it is India that should be honored instead However, old Chinese documents describe long tradition in making various black powder charges for use in firecrackers and rockets mostly for frighten bad spirits during religious happenings and during various festivals and celebrations. The Chinese also developed rockets and flame torches to be used in combat against their main enemy, the Mongols.

Rocket History 2 The Arabs learned the art of rocketry from the Mongols and the Europeans from the Arabs. The Europeans developed the rocket technology further, i.e. between the 14th and 16th century: A English munch named Roger Beacon improved the black powder prescription for use as rocket propellant, fire crackers and for use in canons. A French man improved the hit accuracy of his artillery rockets by launching them from tubes. An Italian (Fontana) experimented with rocket powered surface torpedoes which could ran into the cavalry or set ships on fire. One successfully did!!

Rocket History 3 The interest of the rocket as a weapon went into a hibernation during the 17th century, mainly because of the poor accuracy compare to the more accurate and destructive canon. Further improvements were necessary. A new dawn of rocketry appeared during the 18th century and especially some hundred years after Sir Isacc Newton had published his famous three laws. During the 19th and 20th century many men were to become well know: Ziolkowsky, Hermann Oberth, Robert H. Goddard, Eugen Sänger, Werner von Braun, Korolev and many more

Rocket History 4 Apollo 11 and Neil Armstrong – First man on the Moon 20. July 1969 After the WWII the race for space between USA and former Soviet escalated and accelerated the development of rocket technology to what we know and use today. Vostok 1 and Yuri A, Gagarin – First man in space 12. April 1961 Sputnik I – World first artificial satellite launched 4. October 1957

The Rocket Principle 1 Newtons 2. law: Newtons 3. law: force = opposite force

The Rocket Principle 2 A chemical rocket is a reaction device that brings with itself the oxygen needed for combustion and thus for generating thrust for positive propulsion

Rocket Elements – Main Parts Vc i t e F Vt Ve Convergent Divergent section section c : chamber i : entrance t : throat e : exit V: velocity

Rocket Elements - Thrust Ambient Pressure Ambient Pressure Exit Pressure F Ambient Pressure

Rocket Elements - Nozzle Flow

Rocket Elements - Nozzle Flow Entrance Throat Exit Pe>Pa (under expansion) Pe=Pa (optimum expantion) Pe<Pa (over expansion) M~0 M=1 M>3 P=Pk Ph~0.5Pk Pe Subsonic Transonic Supersonic

Rocket Elements - Nozzle Flow

Rocket Elements - Total Impulse

Static Firing a Rocket Motor NSR 30kN Hybrid Rocket Motor, 20s test

Rocket Elements - Specific Impulse

The Solid Propellant Rocket Construction: Thermal Insulation Motor Case Nozzle Propellant Igniter

Solid Propellant Rocket PARAMETER CHARACTERISTIC VALUE RANGE Specific Impulse [m/s] 2000-2600 Burn rate [mm/s] 1-15 Chamber Pressure [MPa] 7-20 Combustion Efficiency [-] 0.95-0.98 Thrust to Weight Ratio High Throttle? Difficult Stop and Restart? Not Practical Lifetime? Long (7 to 15 years)

The Solid Propellant Rocket Propellant Mixing: 300 gallon  approx. 1200kg of propellant

The Solid Propellant Rocket Propellant Grain Geometry:

Advanced Grain Burn Evolution

The Solid Propellant Rocket Ariane 5 Solid Rocket Booster: DATA for one SRB Propellant: HTPB Propellant Mass: 237T (158 cars) Motor Mass: 273T (182 cars) Thrust: 5400kN (about 550T!!!!) Burn Time: 130s (2.16min) Mass Consumption: 1.82T/s TVC: +/-6deg vectorable nozzle

The Liquid Propellant Rocket Constructions:

The Liquid Propellant Rocket PARAMETER CHARACTERISTIC VALUE RANGE Specific Impulse [m/s] 2500-3800 Burn Rate [mm/s] N.A Chamber Pressure [MPa] 2-10 Combustion Efficiency [-] 0.95-0.98 Thrust to Weight Ratio Low Throttle? Easy Stop and Restart? Lifetime? Very Long (> 10 years)

The Liquid Propellant Rocket

The Liquid Propellant Rocket

The Liquid Propellant Rocket

Pressurized Nitrogen or Helium The Hybrid Rocket Pressurized Nitrogen or Helium Start/stop Valve and pressure regulator Valve Electronics Check Valve Injector “Mixing” Zone Solid Grain Flow Valve and Regulator with control electronics Liquid Nozzle Combustion Chamber

The Hybrid Rocket PARAMETER CHARACTERISTIC VALUE RANGE Specific Impulse [m/s] 2100-3200 Regression rate [mm/s] 0.2-5 Chamber Pressure [MPa] 2-5 Combustion Efficiency [-] 0.90-0.95 Thrust to Weight Ratio Medium Throttle? Easy Stop and Restart? Lifetime? Very Long (>10 years)

The Hybrid Rocket Combustion Principle – The Candle Light Gas (H, C) Liquid Air Air Paraffin Wax

The Hybrid Rocket

The Hybrid Rocket

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