Como Construir, Diseñar Y Probar Pequeños Cohetes

HOW to DESIGN, BUILD and TEST SMALL LIQUID-FUEL ROCKET ENGINES

ROCKETLAB /

CHINA LAKE, CALIFORNIA

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NOTICE
ROCKETLAB cannot assume responsibility, in any manner whatsoever, for the use readers make of the information presented herein or the devices resulting therefrom.

CORRESPONDENCE
Comments regarding this booklet should be sent to:

Note: The following address has not beenverified and may not be current, since it was the address listed in the original text from 1967.
ROCKETLAB Post Office Box 1139 Florence, Oregon 97439

COVER PHOTOGRAPH
Exhaust plume from small 75-lb thrust water cooled liquidfuel rocket engine. Propellants are gaseous oxygen and methyl alcohol. Official U. S. Navy photograph.

Note: Photograph mentioned was not included in this PDF versiondue to it’s poor quality (my copy of the book is pretty ragged) and it appears to be the quality of a Xerox copy to start.

Copyright „ 1967 by Leroy J. Krzycki Printed in the United States of America First printing: March 1967
Second printing: March 1971 ISBN 9600-1980-4 PDF version created by Tim Patterson, http://www.rocketry.org/~tim/

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HOW to DESIGN, BUILD and TEST SMALL LIQUID-FUELROCKET ENGINES CONTENTS

5 7 12 13 13 17 18 19 20 21 23 26 33 34 39 39 39 48 51 53 55 60 61 63 70 71

INTRODUCTION PROPELLANT CHOICE PROPELLANT PROPERTIES DESIGN EQUATIONS Nozzle Combustion Chamber Chamber Wall Thickness Engine Cooling Heat Transfer Materials Injectors EXAMPLE DESIGN CALCULATION Design FABRICATION TESTING EQUIPMENT Feed System Feed System Components TEST STAND SAFETY EQUIPMENTENGINE CHECK-OUT AND CALIBRATION IGNITION AND OPERATION THE LAW BIBLIOGRAPHY LIST OF SUPPLIERS CONVERSION FACTORS ADDITIONAL ONLINE RESOURCES (Added 03/2003)
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FOREWORD
The rocket engine is a relatively simple device in which the propellants are burned and the resulting high pressure gases are expanded through a specially shaped nozzle to produce thrust. Gas pressurized propellant tanks andsimple propellant flow controls make operation of a small liquid-fuel rocket engine about as simple as operating an automobile engine. When then do so many amateur rocket engines fail or cause injury? The reason, usually and simply, is that the amateur is not accustomed to high pressure devices operating near material temperature limits. His normal every day life is, instead, filled with devicesand gadgets operating at low pressures and at low thermal energy levels. With proper design, careful workmanship, and good test equipment operating in a safe manner, the amateur can build small liquid-fuel rocket engines which will have hours of safe operating life. The purpose of this publication is to provide the serious amateur builder with design information, fabrication procedures, testequipment requirements, and safe operating procedures for small liquid-fuel rocket engines.
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HOW to DESIGN, BUILD and TEST SMALL LIQUID-FUEL ROCKTET ENGINES

INTRODUCTION
A liquid rocket engine employs liquid propellants which are fed under pressure from tanks into a combustion chamber. The propellants usually consist of a liquid oxidizer and a liquid fuel. In the combustion chamber thepropellants chemically react (burn) to form hot gases which are then accelerated and ejected at high velocity through a nozzle, thereby imparting momentum to the engine. Momentum is the product of mass and velocity. The thrust force of a rocket motor is the reaction experienced by the motor structure due to the ejection of the high velocity matter. This is the same phenomenon which pushes a garden hosebackward as water squirts from the nozzle or makes a gun recoil when fired. A typical rocket motor consists of the combustion chamber, the nozzle, and the injector, as shown in Figure 1. The combustion chamber is where the burning of propellants takes place at high pressure.

Figure 1 Typical Rocket Motor
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The chamber must be strong enough to contain the high pressure generated by, and...