Model High-Lift Airfoils with Two Constant-Velocity Segments on Their Contours

The problem of designing a symmetrical airfoil with a piecewise-constant velocity distribution on its contour is considered. A range of governing parameters corresponding to physically realizable airfoils is determined. The optimal properties of the airfoils constructed are studied.     

Design of an airfoil with a flap of finite dimensions

A method of designing mechanized profiles is proposed. This method preserves the advantages of inverse boundary-value problems for simply connected domains and makes it possible to use quasi-solutions for satisfying the conditions of solvability. The problems of designing a profile with an infinitely thin flap of finite length and an airfoil with a flap of finite thickness are considered.Kazan'. Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 1, pp. 173–180, January–February, 1995.     

Design of airfoil with flap simulated by a point vortex

The method of quasisolutions of inverse boundary-value problems (see [4]) is used to solve the problem of designing an airfoil with a flap, replaced by a fixed vortex, from given velocity distribution along the contour of the wing main part. Profiles are constructed and the effect of the flap (vortex) on the shape and aerodynamic properties of the mechanized wing is examined.Translated from Izvestiya Rossiiskoi Akademii Nauk, Mekhanika Zhidkosti i Gaza, No. 1, pp. 3–9, January–February, 1992.     

Airfoil design using quasisolutions of inverse boundary-value problems

A mathematically rigorous approach to the solution of inverse boundary-value problems of aerohydrodynamics — problems in which the airfoil contour is found from the given distribution of the velocity as a function of the arc abscissa – is proposed. The approach is based on the notion of a quasisolution in the theory of improperly posed problems and involves a controlled modification of the initial data for the purpose of obtaining a unique solution in a given class of contours. The approach is explained with reference to the problem of designing an isolated airfoil in a plane steady ideal incompressible flow and is extended to the cases of subsonic gas flow and viscous incompressible flow. Some numerical results illustrating the possibilities of the method are also presented.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 3, pp. 5–13, May–June, 1988.The authors wish to thank G. Yu. Stepanov for frequent useful discussions and valuable advice.     

Pole model for nonlepton and radiative hyperon decay

Nonlepton and weak radiative decays of hyperons are analyzed on the basis of the pole model. In contrast with other analyses, the contributions from both baryon and meson poles are taken into account. Experimental information on these decays is used to find the parameters of the effective weak two-baryon interaction.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii Fizika, No. 8, pp. 17–22, August, 1969.The author thanks V. A. Filimonov and G. M. Radutskii for stimulating discission of this study.     

Setup for studying quasi-free neutron-neutron scattering in the energy range of 20–60 MeV

A setup installed on the RADEX neutron beam channel (Institute for Nuclear Research, Russian Academy of Sciences) and designed to study quasi-free nn scattering in the n + d → p + n + n reaction is described. The setup is a two-arm time-of-flight spectrometer composed of scintillation neutron hodoscope (in the left arm), a scintillation neutron detector (in the right arm), and an active scintillation deuterated target for detecting protons. Secondary neutrons are detected at angles corresponding to the kinematic conditions of quasi-free nn scattering. Events are selected at low energies of the outgoing proton spectator. It is shown that data on neutron-neutron quasi-free scattering can be obtained in a wide range of primary-neutron energies.     

Description of small-angle neutron scattering data for nickel–chromium–aluminum alloy within quantum mechanics and classic polydisperse sphere model

The modified Yukawa potential is used to fit the nucleus model parameters to the data on small-angle neutron scattering on nickel—chromium—aluminum alloy for the product of the transferred momentum Q and the effective nucleus radius R, satisfying the condition QR ≤ ?. The analytical polydisperse sphere model is used to calculate the neutron scattering intensity and to determine the most probable macroscopic sphere radius R ₀ at QR ₀ ≥ 3?.     

Plasma channel formation in nitrogen upon electron beam injection

A theoretical study is performed of plasma channel formation and current neutralization upon injection of a high current electron beam into nitrogen under high pressure (p 70 torr). The complex ion formation and recombination mechanism is considered together with its effect on the parameters of the plasma formed and the dynamics of beam current neutralization. Analytical expressions are obtained for the densities of simple and complex ions in the limiting cases and numerical calculations are carried out by computer for a more general case. It is shown that in nitrogen at a pressure of 70 torr when complex ions are considered the plasma channel conductivity decreases by approximately 35–40%.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 12, pp. 59–65, December, 1990.     

Data Correction Method for Improving the Spatial Resolution of a Position-Sensitive 10B Neutron Detector

Physics of Atomic Nuclei - A technique for correcting experimental data from a position-sensitive neutron detector with an active layer of solid boron-10, where the charge division method is used...     

Data on Neutron–Neutron Scattering Length from the Reaction $$\boldsymbol{n+^{2}\textrm{H}\to n+n+p}$$ at $$\boldsymbol{E_{n}=60}$$ MeV

Physics of Atomic Nuclei - The $${}^{1}S_{0}$$ neutron–neutron ( $$nn$$ ) scattering length was measured in the neutron–deuteron ( $$nd$$ ) breakup reaction at an energy of 60 MeV. The...