Khristianovich, Sergei Alekeyevich

Russian specialist in fluid mechanics. His work at TsAGI was important in the early design of ballistic missiles up to 1953. From 1953 he worked at the Institute of Theoretical and Applied Mechanics in Novosibirsk.

Biography: S. A. Khristianovich was born October 27, 1908. In 1930 he graduated from the Leningrad Institute and then worked in the State Hydrological Institute in Leningrad. From 1937 to 1953, he was at the Central Aerohydrodynamic Institute. He was a Member of the Presidium of the USSR Academy of Sciences in 1946 to 1956. In 1956 he started working in the Institute of Chemical Physics of the USSR Academy of Sciences. Khristianovich became a member of the Communist Party of the Soviet Union in 1949. He was elected a Corresponding member of the USSR Academy of Sciences in 1939, and in 1943 an Academician. In 1942, 1946, and 1952 he was awarded Stalin Prizes.

Khristianovich's field of work was mechanics of liquids and gases. In his monograph, "Irregular Movement in Canals and Rivers" (1938) he solved the problem of spreading and reflection of waves and applied these results to hydrotechnical structures. In plasticity, he solved the surface problem of the determination of the tension arising in a plastic medium in terms of the forces set in a closed contour. On the theory of filtration, Khristianovich wrote in 1940 "The Movement of Subsoil Waters, Not Following the Darcy Law" and in 1941 "On the Movement of Aerated Liquids in Porous Rocks." In aerodynamics, he studied the flow of gas at high subsonic speeds around a profile in the presence of lifting force, and worked out a method of calculating the effect of compressibility on the characteristics of wing profiles. He carried out important studies on the flow of gas at supersonic speed, and also in aviation technology.

As of 1961, Khristianovich was a Vice President of the Siberian Department of the U.S.S.R. Academy of Sciences, Director of the Institute of Theoretical and Applied Mechanics (Novosibirsk), and a Member of the Presidium of the USSR Academy of Sciences.