Zhukovskii, Nikolai Egorovich

Born Jan. 5 (17), 1847, in the village of Orekhovo, present-day Vladimir Oblast; died Mar. 17, 1921, in Moscow. Russian scientist in the field of mechanics; founder of modern hydrodynamics and aerodynamics. Son of a railroad engineer. Graduated from the department of physics and mathematics of Moscow University in 1868, specializing in applied mathematics. In 1870 he became a physics teacher at the Second Moscow Women’s Gymnasium. In 1872, Zhukovskii became a lecturer in mathematics and in 1874 an assistant professor in the sub-department of analytical mechanics of the Moscow Higher Technical School. In 1876 he defended his master’s thesis, Kinematics of Liquids. Zhukovskii received the degree of doctor of applied mathematics in 1882 for his work On the Stability of Motion. In 1885 he began to teach theoretical mechanics at Moscow University. He worked at Moscow University and the Moscow Higher Technical School until his death.

In 1894, Zhukovskii was elected corresponding member of the St. Petersburg Academy of Sciences. In 1900 he was presented as a candidate for election to full membership in the St. Petersburg Academy of Sciences but withdrew his candidacy, since he did not want to give up teaching at Moscow University and the Moscow Higher Technical School (election would have meant a move to St. Petersburg). In 1905 he was elected president of the Moscow Mathematical Society.

In 1902, Zhukovskii directed the construction of a wind tunnel for the Mechanics Laboratory of Moscow University; it was one of the first wind tunnels to be built in Europe. The first institute of aerodynamics in Europe was organized under his leadership in 1904 in the village of Kuchino, near Moscow. During the same year Zhukovskii organized the Aeronautics Section of the Society for the Advancement of Natural Sciences, Anthropology, and Ethnology. In 1910, Zhukovskii took an active part in the organization of an aerodynamics laboratory at the Moscow Higher Technical School. In 1910–12 he gave a series of lectures at the Moscow Higher Technical School entitled “The Theoretical Foundations of Aviation,” which contained a systematic presentation of the work done by Zhukovskii and by his student, S. A. Chaplygin, as well as experimental studies conducted in the aerodynamics laboratories of Moscow University and the Moscow Higher Technical School and in laboratories abroad. In 1913, Zhukovskii began to give lectures for air force pilots at the Moscow Higher Technical School, where a bureau for design and testing of aircraft was organized. Methods for aerodynamic calculations and for structural design of aircraft were developed at the bureau under Zhukovskii’s direction. During World War I (1914–18), Zhukovskii developed the theory of bombing, studied problems in the ballistics of artillery projectiles, and gave courses in ballistics, aviation, and special problems in hydromechanics; he also worked on various problems of theoretical mechanics.

After the October Revolution Zhukovskii, together with a group of scientists under his direction, immediately devoted himself to the task of creating a Soviet air force. In December 1918, at Zhukovskii’s suggestion, the Soviet government established the Central Aerodynamic and Hydrodynamic Institute, which was directed by Zhukovskii. The theoretical courses for air force pilots established by Zhukovskii were reorganized as the Moscow Aviation Technicum, which in turn served as the basis for the development of the Engineering Institute of the Red Air Force (since 1922 the N. E. Zhukovskii Air Force Engineering Academy).

Zhukovskii created a unified engineering discipline, experimental and theoretical aerodynamics, whose development was closely associated with progress in aircraft construction. His earliest research on the theory of flight was conducted in 1890. His papers On the Soaring of Birds (1891), in which the mechanism of soaring with concurrent ascent was studied and the possible evolutions in soaring (including the “normal loop”) were examined, and On the Optimum Angle of Inclination of an Airplane (1897) were the basis of aerodynamic calculations for aircraft design. In the articles “On the Theory of Flight” (1890), “On Alate Propellers” (1898), and “On the Payload Lifted by a Helicopter” (1904) he dealt with problems of propeller thrust. In the works On the Fall in Air of Light, Elongated Bodies Rotating About Their Longitudinal Axes (1906) and On Bound Vortices (1907), Zhukovskii stated the principle of generation of the lift of an aircraft wing, which he discovered in 1904, and formulated a theorem that makes possible the determination of the magnitude of the lifting force. Zhukovskii’s theorem, which establishes the link between circulation and the lift of an airfoil, is the basis of aerodynamics. A hypothesis about the escape of the slipstream from the trailing edge, which yielded a method for the determination of circulation and confirmed the fundamental significance of Zhukovskii’s theorem for aviation, was proposed in the group of works by Zhukovskii On the Contours of Airfoils in Airplanes (1910) and Geometric Research on Kutta’s Flow (1911–12), as well as in a number of works by S. A. Chaplygin. These works evolved a mathematical model for solving problems of flow over an airfoil and presented a method for designing theoretical Zhukovskii wing profiles. From 1912 to 1918, Zhukovskii published four articles under the common title Vortex Theory of a Propeller, in which, based on the airfoil theory he had developed, he determined the laws of velocity distribution on propeller blades, which were the theoretical foundation of propeller design.

In his works An Elementary Treatment of Aircraft Dynamics ( 1913–16), Aerodynamic Design of Aircraft (1917), Study of the Stability of Aircraft Designs (1918), On the Question of Structural Strength of Aircraft (1918), and Elementary Theory of Aircraft Stability (1920), Zhukovskii created the foundation for aerodynamic design of aircraft and for calculations of the dynamic longitudinal stability and structural strength of airplanes.

Zhukovskii was the author of numerous original research works on mechanics of rigid bodies, astronomy, mathematics, hydrodynamics and hydraulics, applied mechanics, and machine control theory. His work is characterized by the combination of in-depth theoretical research with an engineering approach to the solution of technical problems. He also was the author of theoretical mechanics textbooks that have become classics and are used in universities and technical institutions of higher learning.

To celebrate 50 years of Zhukovskii’s scientific work and his services as the “father of Russian aviation,” a decree was promulgated by the Council of People’s Commissars and signed by V. I. Lenin in 1920 establishing the N. E. Zhukovskii Prize for the best works in mathematics and mechanics and providing for the publication of Zhukovskii’s works and for the award of a number of privileges to Zhukovskii himself. In January 1947, on the 100th anniversary of Zhukovskii’s birth, the Council of Ministers of the USSR established two annual N. E. Zhukovskii prizes and N. E. Zhukovskii scholarships for senior students at Moscow University, the Moscow Aviation Institute, and the N. E. Bauman Moscow Higher Technical School. Memorials have been erected in Moscow and in the city of Zhukovskii in Moscow Oblast. A Zhukovskii memorial museum has been established in Moscow, and a museum in Zhukovskii’s native region has been renovated.