Professor John H. S. Lee: The Detonation Phenomenon

Abstract

The book “The Detonation Phenomenon” by Professor John H. S. Lee is intended for engineers and graduate students with backgrounds in thermodynamics and fluid dynamics. It fulfills that mission perfectly. The book is an excellent, thorough review of the basic experimental and theoretical aspects of gas phase detonation. Gas phase detonation has frequently been studied, because its three-dimensional shock wave structure can be photographed, the pressure it produces is not extreme, as opposed to that of a solid or liquid explosive, and the chemical reaction rates that control its propagation can be measured in shock tubes. Professor Lee has assembled a wonderful combination of fantastic photographs from all over the world plus basic theoretical explanations of the various phenomena involved in gas phase detonation. The book has a mechanical engineering slant, emphasizing the structures of shock and detonation waves and their interactions with surrounding materials. The book covers the discovery of detonation with pictures of the scientists who uncovered the basic properties of detonation waves. The first three chapters and part of Chapter 4 contain necessary experimental and theoretical background found in other books, but this information is presented in a very clear concise manner. Each chapter ends with closing remarks, which often contain a list of unsolved problems. The bibliographies at the end of each chapter contain most of the relevant references. The remaining chapters of “The Detonation Phenomena” are unique and brilliantly presented. Chapter 5 is a numerical analysis of unstable detonation that provides an excellent summary of several complex topics. Professor Lee systematically discusses: linear stability analysis; asymptotic modeling; direct computer simulations; and chemical effects on the stability of detonation waves. He ends Chapter 5 with its main message that theory and numerical modeling support that the experimental fact that all detonation waves are unstable and exhibit multi-dimensional wave structures. Chapter 6 is entitled “Unstable Detonations: Experimental Observations.” It begins with the 1926 discovery of “spinning detonation” and presents photographs and explanations of all of the detonation flows discovered thus far. This chapter is by far the best collection of famous photographs from many authors of detonation wave structures. Many cases of multi-headed detonation waves and the triple shock intersection points that control their propagation are illustrated. The effects of various geometries on the “cellular structures” produced by the interactions of these “triple points” are covered more completely than in other books on gaseous detonation. Chapter 6 ends with a basic discussion of how chemical energy release controls detonation wave cell size. Chapter 7 discusses the influence of boundary conditions on gaseous detonation wave propagation. The influences of rough versus smooth walls (turbulent flow) on detonation velocity and cellular structures are important engineering concerns that are covered very well in Chapter 7. An imaginative experiment developed by Professor Lee’s group was to pass a detonation wave over an acoustically absorbing material. When the triple shock intersection points of a detonation waves interacted with this material, the cellular structure of the detonation was destroyed. The detonation wave exited that section of tube as a planar shock wave followed by a deflagration wave. This experiment proved that the cellular structure was essential to gas phase detonation