A discussion on detonation

Abstract

The fundamental physical, chemical and mechanical processes which occur when a detonation wave passes through an explosive were imperfectly understood at the beginning of the recent war. As part of the scientific war effort in the British Common-wealth and in the United States of America, many theoretical and experimental studies were made of detonation processes. Much of the work has recently been declassified and some has been published. Several centres of research in this country and elsewhere are vigorously continuing with these studies. As later papers will show, the quality and general scientific interest of much of this work was considered sufficient to form the basis of a Discussion of the Royal Society. If one neglects the finite width of the zone in the detonation front where chemical reactions occur, a freely running steady plane detonation front can only advance through an explosive with the Chapman-Jouguet velocity defined by D = u+c. Once the explosive products are formed, their subsequent chemical reactions and motion in the detonation front may be considered as adiabatic. Although Chapman (1899) and Jouguet (1901) correctly stated their equation, neither attempted to discuss the reaction zone itself. It was therefore thought necessary that the recent views on the reaction zone should be described in a manner which throws new light on the Chapman-Jouguet equation. Professor J. von Neumann, Dr⋅ S. F. Boys and Dr A. F. Devonshire were the principal contributors on the theoretical side and von Neumann’s theory (1942) will be outlined later.