Compressibility is a property inherent in any material, but it does not always manifest itself. Experience suggests that it affects the medium motion only at velocities comparable to the speed of sound.
Why do we study compressibility? It turns out that in order to calculate the aircraft streamlining or the internal flow in its engine, or the shell muzzle velocity, or the dynamic load of a shock wave from an accidental blast on a structural element, and in many other cases it is necessary to know and understand the laws of the Dynamics of Compressible Media (DCM) and be able to apply them in practice. This textbook is designed to help readers achieve this goal and learn the basics of DCM.
This field of knowledge is high-tech and always focuses on the future: modern developments of hypersonic aircraft, designing more advanced structural elements for airplanes and helicopters, calculating the car aerodynamics, etc.
Paradoxes have always given impetus to the search for new technological devices. Unusual effects in DCM include the flow chocking in supersonic outflow from reservoirs (Sect.2.2); the shock wave formation inside an initially smooth flow (Sect.5.3); the generation of a "spallation saucer" of armor inside a tank when a shell hits it (Sect.5.5); the dog-leg of a plane discontinuity surface at shockwave reflection from a rigid wall (Sec.8.1).
The way to understand these and other effects is through the creation of quantitative models of a moving compressible fluid.
About the Author: Oleksandr Georgiyevich Girin was born on 1st of February, 1951, in the city of Zhytomir, Ukraine.
Educational background: O. G. Girin graduated from the Novosibirsk State University (Department of Hydrodynamics) in 1973 with a degree in Mechanics, Applied Mathematics. He worked on his specialist diploma and defended it in the Lavrent'ev Institute of Hydrodynamics. Being a graduate student, he worked as a laboratory assistant in the Research Laboratory of Explosive Processes at the Lavrentiev Institute of Hydrodynamics. After graduating university, he worked at Altay Research Institute, Biysk, Altay Region, Russia, as an engineer and junior researcher. From 1976 to 1979, he was a postgraduate student at Odessa State University, Odessa, Ukraine. In 1979-1984, he worked in the Department of Theoretical Mechanics as an assistant and junior lecturer. He received his Ph.D. Diploma in Theoretical Physics from Odessa State University in 1984. He was then hired as a lecturer and an associate professor at Odessa State University. For the next 24 years, he worked as an associate professor in the Department of Theoretical Mechanics, lecturing the following courses: theoretical mechanics, fluid dynamics, gas dynamics, dynamics of viscous fluids, dynamics of heterogeneous media, numerical methods in gas dynamics, special chapters of computational fluid dynamics, theory of combustion and detonation. He gave lecture courses, conducted practical classes and laboratory works, supervised diploma works. From 1989 to 1998, he was deputy dean of the Faculty of Mathematics and Mechanics for scientific work. He is an author of lecture courses "Gas Dynamics" (in Ukrainian, 2007) and "Numerical Methods in Gas Dynamics" (in Ukrainian, 2006). Both courses were approved by the Ministry of Education and Science of Ukraine as textbooks for mechanics departments of universities and published by "Astroprint" Publishing House at the Odesa National University with the stamp of the Ministry. Later in 2012, these courses were published by Palmarium Academic Publishing, Deutschland, as a combined textbook "Fundamentals and Numerical Methods of Gas Dynamics" (in Russian). In 2010, he worked at Odesa State Environmental University, Odesa, Ukraine, as an associate professor at Department of General and Theoretical Physics. He taught lecture courses, practical studying and laboratory works.
Scientific interests of him lie in theoretical gas dynamics; hydrodynamic instability of gas-liquid interface; modelling and investigation of the mechanics of liquid atomization; theory of heterogeneous media motion, in particular--detonation wave structure and its self-sustainability; investigation of the combustible mixture formation and process of explosion at detonation wave development in two-phase media; mechanisms of meteoroid ablation. He has the academic title of associate professor; he is also the author of 70 peer-reviewed articles in 15 different journals. At present, he is retired, on pension.
