Turbulent reactive flows are of common occurrance in combustion engineering, chemical reactor technology and various types of engines producing power and thrust utilizing chemical and nuclear fuels. Pollutant formation and dispersion in the atmospheric environment and in rivers, lakes and ocean also involve interactions between turbulence, chemical reactivity and heat and mass transfer processes. Considerable advances have occurred over the past twenty years in the understanding, analysis, measurement, prediction and control of turbulent reactive flows. Two main contributors to such advances are improvements in instrumentation and spectacular growth in computation: hardware, sciences and skills and data processing software, each leading to developments in others. Turbulence presents several features that are situation-specific. Both for that reason and a number of others, it is yet difficult to visualize a so-called solution of the turbulence problem or even a generalized approach to the problem. It appears that recognition of patterns and structures in turbulent flow and their study based on considerations of stability, interactions, chaos and fractal character may be opening up an avenue of research that may be leading to a generalized approach to classification and analysis and, possibly, prediction of specific processes in the flowfield. Predictions for engineering use, on the other hand, can be foreseen for sometime to come to depend upon modeling of selected features of turbulence at various levels of sophistication dictated by perceived need and available capability.

Supersonic combustion ramjet (SCRJ) engine research and development begun some 40 years ago is the key to airbreathing hypersonic flight. Many unexpected complexities of SCRJ engine combustion and combustor-inlet interaction have been continuing challenges. However, valuable progress has been made in several aspects. In the next few years, it would appear that significant flight testing will take place in several countries and this should lead to further understanding of SCRJ processes in engine design for cruise and accelerator vehicle applications. This volume - the third and final in a mini-series on hypersonic propulsion along with High Speed Flight Propulsion Systems, volume 137, and Developments in High Speed Flight Propulsion Systems, volume 165 - presents a comprehensive and detailed exposition of the gradual maturing of scramjet technologies. Developments in several parts of the world are described by those intimately involved in the main stream of SCRJ activities. It is clear that fresh opportunities exist to improve the robustness of high-speed-fight propulsion, and this book offers a timely lead to a new entrant to this technology as well as new insights to specialists.

There have been impressive achievements in the last few years in the technologies associated with turboramjets and other combined cycle engines. These technologies, including their thermal management and integration with the vehicle, are the principal concerns of this volume. Drawing on the expertise of international engineers and researchers in the field of high-speed vehicle propulsion systems, these articles, written by experts from the United States, Russia, Germany, Japan, Belgium, and Israel, highlight developments in the industry.