Felix Isidorovich Frankl
(to the 120th birthday)
Felix Isidorovich Frankl (1905-1961) – outstanding scholar in the field of mathematics, mechanics, mathematical and theoretical physics, doctor of physics and mathematics and technical sciences, professor, author of more than 90 scientific papers dedicated to various branches of aerogasdynamics, issues of continuum mechanics, topology, which have great theoretical and applied significance.
F. I. Frankl was born on March 12, 1905 in Vienna. In 1927 he graduated from the University of Vienna, and in 1929 – emigrated to the USSR, where in the same year he entered the Communist Academy under the Central Executive Committee of the USSR as a research fellow. In 1927-1931, the first works of F. I. Frankl were published, in which he laid out a number of important studies obtained for topology science.
From 1931 to 1944 is the main period of scientific activity when F. I. Frankl works as a research fellow and scientific director, first in the physics and mathematics department, and then in other departments of the Central Aerodynamic Institute (CAI). Most of his fundamental research on various issues of hydroaerodynamics, gas dynamics and related branches of applied mathematics and mathematical physics belong to these years. Among those works, the most famous were on gas dynamics and, above all, on supersonic flow around bodies and on transonic flows.
F. I. Frankl was the first to conduct research on the theory of laminar and turbulent boundary layers in high-speed gas flows. Moreover, jointly with M. V. Keldysh, he proposed a nonlinear blade propeller theory with an infinite number of blades through which incompressible fluid flows, and subsequently the foundations for the theory of flat profiles cascades and a blade propeller with an infinite number of blades in a gas flow.
F. I. Frankl formulated and solved a number of new boundary value problems for equations of mixed elliptic-hyperbolic type and made the first attempt to construct a local subsonic zone in supersonic jets without a closing shock. The monograph “Fundamentals of Gas Dynamics”, published in collaboration with S. A. Khristianovich and R. N. Alekseeva, played a major role in the development of the gas-dynamic study.
Felix Isidorovich was one of the most enthusiastic founders of the special physic and aerodynamic sector in the Central Aerodynamic Institute (CAI), which immediately became and retained its significance for a long time as a center for Soviet theoretical and experimental research in gas dynamics, boundary layer theory, turbulence and thermal processes in gas flows. The most important joint researches were carried out then, involving numerous talented scientists and young researchers.
In the years of the Great Patriotic War F. I. Frankl continued his scientific activity: using the source method, he obtained a solution to the problem of incompressible fluid flow around bodies that are close to axisymmetric, both for solid bodies and bodies with fluid passing through them. In 1944, Felix Isidorovich was appointed to the Felix Dzerzhinsky Artillery Academy, where he continued working on supersonic flow around elongated bodies of revolution, flows in nozzles and the outflow of supersonic jets. The famous monograph (co-authored with E. A. Karpovich) “Gas Dynamics of Subtle Bodies” also dates back to this period and received wide recognition both here and abroad.
In 1950, due to his political views, Felix Isidorovich was forced to move to the city of Frunze. Head of the department of theoretical physics at the Kyrgyz State Pedagogical Institute (since 24.05.1951 – Kyrgyz State University (KGU)), F. I. Frankl created a scientific school of relativistic gas dynamics. In less than 8 years at KSU, F. I. Frankl prepared more than 20 candidates of science. Currently, the F. I. Frankl Center operates at the Kyrgyz National University named after Zhusup Balasagyn.
F. I. Frankl paid great attention to the development of ideas of the general theory of relativity. Being an excellent mathematician, he published a number of interesting papers on the formulation of the Cauchy problem in solving the equations of general relativity. His polemics with V. A. Fock showed the full complexity of the problem, which could not be solved in a general way. Only for a special case, with the introduction of so-called harmonic coordinates, was the Cauchy problem solved correctly.
In 1957, F. I. Frankl invited by then rector of Kabardino-Balkarian State University (KBSU) Kh.M.Berbekov moved to Nalchik. Here passed Felix Isidorovich’s last years full of creativity and activity in science popularization among the youth. During this time, new scientific papers on gas dynamics continued to be published, mainly in the field of transonic flows. The last publications include works on semi-classical representations of the equations of quantum mechanics, study of hydraulic engineering and dynamic meteorology (the theory of sediments and sand waves in the desert, the movement of water in the bed of small fast rivers, the thermohydrodynamic model of the Bora and many others).
Adam Maremovich Nakhushev, an outstanding scientist, Doctor of Physics and Mathematics, Professor, noted that first he knew about elements of fractional calculus and its application at F. I. Frankl’s seminars. Later he used this knowledge in the research on the gas dynamics of transonic flows. A. M. Nakhushev was convinced that “Felix Isidorovich lit the torch of great science at KBSU” and meeting this remarkable scientist considered a great fortune in his life.
F. I. Frankl made a significant contribution to the training of scientific personnel. Many Soviet physicists-mechanics were, to some extent, his students. Under the leadership of F. I. Frankl and in collaboration with him, numerous studies were carried out. The scientific and pedagogical activity of F. I. Frankl reached its peak in the Kyrgyz and Kabardino-Balkarian State Universities, where, under his leadership, dozens of candidate dissertations were prepared and defended in a relatively short period of time.
Felix Isidorovich Frankl – Doctor of Philosophy (Philosophiс Doctor) in the field of Mathematics (University of Vienna, 1927), Doctor of Technical Sciences (1934), Doctor of Physical and Mathematical Sciences (1936). In 1946 he was elected a Corresponding Member (since its establishment, 1946) of the Academy of Artillery Sciences (currently: Russian Academy of Rocket and Artillery Sciences (RARAS)), in 1956 – became a member (since its establishment, 1956) of the USSR National Committee on Theoretical and Applied Mechanics. For outstanding achievements in mathematics and physics, Frankl Felix Isidorovich was awarded the Euler Gold Medal of the USSR Academy of Sciences in 1957.
The name of Felix Isidorovich Frankl has firmly established in the history of development of the theory of mixed-type equations, mechanics of liquids and gases in Russia and abroad. The bright memory of him will remain for a long time in the hearts of his students and followers.