Theory of Solid-Propellant Nonsteady Combustion

Boris V. Novozhilov, Vasily B. Novozhilov

• Publisher: Wiley-ASME Press Series
• Year: 2020
• Print ISBN:
  9781119525707
• eBook ISBN:
  9781119525585
• Edition: 1
• Topic: Tecnologia e ingegneria
• Subtopic: Ingegneria aerospaziale

Despite significant developments and widespread theoretical and practical interest in the area of Solid-Propellant Nonsteady Combustion for the last fifty years, a comprehensive and authoritative text on the subject has not been available. Theory of Solid-Propellant Nonsteady Combustion fills this gap by summarizing theoretical approaches to the problem within the framework of the Zeldovich-Novozhilov (ZN-) theory. This book contains equations governing unsteady combustion and applies them systematically to a wide range of problems of practical interest. Theory conclusions are validated, as much as possible, against available experimental data. Theory of Solid-Propellant Nonsteady Combustion provides an accurate up-to-date account and perspectives on the subject and is also accompanied by a website hosting solutions to problems in the book.

1
Steady‐state Combustion

1.1 General Characteristics of Solid Propellants

There are two types of propellants used in rocket motors: homogeneous and heterogeneous. They differ in both chemical composition and physical structure.

Homogeneous propellants have the fuel and oxidizer bound chemically at the molecular level. The basic component of this type of propellant is nitrocellulose, an ester obtained by nitration of cellulose in nitric acid. Nitrocellulose can gelatinize in various solvents, of which nitroglycerin is the most frequently used. Since such propellants invariably contain two basic components (nitrocellulose and nitroglycerin), they are often called double‐base propellants. Sometimes they are also referred to as smokeless propellants (as they replaced black, or smoke, powder at the end of the nineteenth century) or ballistites.

Before World War II, priority was given to ballistites. Composite (heterogeneous) propellants found wide application in the post‐war period. It should be noted, however, that the first solid propellant was of the composite type; it was the above‐mentioned black powder, which is a mechanical mixture of charcoal, potassium nitrate, and sulphur.

The composite propellant is a mechanical mixture of two or more components. The fuel and oxidizer are not mixed at the molecular level and are separated from each other, therefore such compositions are called heterogeneous propellants. The components of a composite propellant are microscopic particles measuring from a few micrometres to tenths of a millimetre. Sometimes, however, particles of one component are interspersed in the body of the other.

One example of a homogeneous propellant is the American ballistite JPN. By weight, it contains 51.5% nitrocellulose, 43.0% nitroglycerin, 1% centralite, and 4.5% other additives. The centralite is added to improve the chemical stability of the propellant. Such materials are called stabilizers. Centralite reacts with the products of the spontaneous decomposition of a propellant in storage and thus prevents its autocatalytic decomposition. The density of the propellant JPN is 1.62 g/cm³; other double‐base propellants have about t...

Table of contents

• Cover
• Table of Contents
• About the Authors
• Preface
• Important Notation and Abbreviations
• About the Companion Website
• 1 Steady‐state Combustion
• 2 Equations of the Theory of Nonsteady Combustion
• 3 Combustion Under Constant Pressure
• 4 Combustion Under Harmonically Oscillating Pressure
• 5 Nonsteady Erosive Combustion
• 6 Nonsteady Combustion Under External Radiation
• 7 Nonacoustic Combustion Regimes
• 8 Modelling Nonsteady Combustion in a Solid Rocket Motor
• 9 Influence of Gas‐phase Inertia on Nonsteady Combustion
• References
• Theory of Solid‐Propellant Nonsteady Combustion
• Theory of Solid‐Propellant Nonsteady Combustion
• Index
• End User License Agreement