Zhukovskii Central Aerohydrodynamic Institute
Zhukovskii Central Aerohydrodynamic Institute
Bolshov M.A.,Russian Academy of Sciences |
Kuritsyn Y.A.,Russian Academy of Sciences |
Liger V.V.,Russian Academy of Sciences |
Mironenko V.R.,Russian Academy of Sciences |
Kolesnikov O.M.,Zhukovskii Central Aerohydrodynamic Institute
Optics and Spectroscopy (English translation of Optika i Spektroskopiya) | Year: 2017
We have developed a prototype of a diode-laser absorption spectrometer for noncontact determination of the temperature and concentration of water vapor in the combustion zone of mixed supersonic flows. The method is based on fast scanning of the radiation frequencies of two diode lasers in different spectral ranges containing several absorption lines of water molecules, determining the integral intensities of selected lines, and calculating the medium temperature from the intensity ratio of these lines. The described version of the spectrometer allows one to determine the parameters of the gas medium at high pressures (up to 3 atm) and temperatures (up to 2000 K). The criterion of selection of the spectral scanning ranges of the lasers is described, which is based on minimizing the error of determining the temperature at the expected experimental measurement accuracy of the integral intensities of lines. A program for selection of appropriate combinations of lines from spectroscopic databases has been developed. An algorithm for obtaining the temperature by fitting experimental spectra and theoretical spectra simulated using databases has been developed. Errors of determining the temperature for different fitting algorithms have been estimated. We show that, for the temperature estimation to be more accurate, it is necessary to take into account maximal possible number of lines lying in the scanning ranges of the two lasers. © 2017, Pleiades Publishing, Ltd.
Kashevarov A.V.,Zhukovskii Central Aerohydrodynamic Institute |
Stasenko A.L.,Zhukovskii Central Aerohydrodynamic Institute
Journal of Applied Mechanics and Technical Physics | Year: 2017
This paper presents a physicomathematical model for the effect of air flow containing ice crystals on a water film moving along the surface of a solid body. Numerical studies were carried out for the case of a cylinder in transverse flow. The influence of the effective viscosity of the suspension of crystals in the carrier water and the finite time of their melting on the hydro-thermodynamics of the solidifying film. In this case, the employed model is nonlocal. © 2017, Pleiades Publishing, Ltd.
Zaitsev M.Yu.,Zhukovskii Central Aerohydrodynamic Institute |
Belyaev I.V.,Zhukovskii Central Aerohydrodynamic Institute |
Kopiev V.F.,Zhukovskii Central Aerohydrodynamic Institute |
Mironov M.A.,Andreev Acoustical Institute
Acoustical Physics | Year: 2012
A new concept of reducing the noise of a slat by applying a chevron form to the bottom edge is experimentally verified. The results of parametric studies are presented, which have been carried out on a small-scale model of a part of the wing (a scale of 1 : 18) with deflected high-lift devices (the slat and the flap) in the landing configuration. As a result of acoustic measurements, a decrease (up to 4.5 dB) in narrowband noise for some chevron geometries is observed in comparison to a usual slat. The value of the decrease is a complex function of frequency, the wing and slat geometry, and the flow characteristics. © Pleiades Publishing, Ltd., 2012.
Trenisova A.L.,Mendeleev University of Chemical Technology |
Akhmatova O.V.,Mendeleev University of Chemical Technology |
Smotrova S.A.,Zhukovskii Central Aerohydrodynamic Institute |
Gorbunova I.Y.,Mendeleev University of Chemical Technology |
And 3 more authors.
International Polymer Science and Technology | Year: 2012
A study was made of the effect of montmorillonite on the curing of an epoxy oligomer with diaminophenylsulphone. It was shown that the introduction of the clay in all cases leads to an increase in the viscosity of the epoxy oligomer. It turned out that ultrasound has a considerable effect on the viscosity of a composite containing modified clay. © 2012 Smithers Rapra Technology.
Zaveryukha G.G.,Zhukovskii Central Aerohydrodynamic Institute
Russian Engineering Research | Year: 2010
The fatigue life of structural elements in multiaxial loading may be assessed on the basis of the balance of fatigue strength, taking account of the change in stress-strain state in multiaxial and uniaxial loading. © 2010 Allerton Press, Inc.
Manuilovich S.V.,Zhukovskii Central Aerohydrodynamic Institute
Doklady Physics | Year: 2014
The main cause of the turbulent flow character in the boundary layer on a wing of a modern airplane is the wing sweep. The flow acceleration in the vicinity of the leading edge and the sliding effect lead to the formation of cross flow in the boundary layer, namely the air motion along the wing surface in the direction perpendicular to the external flow velocity. The optimal configuration of the force effect can be used when designing the system of actuators for cross flow cancellation in the boundary layer on a swept wing. The solid and dashed lines denote the cases of the force effect and its absence, respectively. In the absence of the effect, the thickness of the boundary layer increases monotonically. The applied force leads to considerable thickening of the boundary layer in the vicinity of the attachment line. Then the thickness of the boundary layer decreases and turns out to be almost equal to the thickness in the absence of the effect.
Molleson G.V.,Zhukovskii Central Aerohydrodynamic Institute |
Stasenko A.L.,Moscow Institute of Physics and Technology
High Temperature | Year: 2015
In continuing studies [1–4] in which optics and electrification of particles colliding with a body around which a high-speed two-phase jet flows are considered, there was an attempt to explain the experimentally observed luminescence  of a conducting body, bombarded by microparticles, by the presence of a reverse unipolar current (from rebounded particles) exciting carrier-gas molecules. The process of charge acquisition by a particle in collision with a solid is complex: not only the value of the charge but even its sign are unknown in many cases . A simple model is proposed for estimating the characteristic values of the reverse current density and the spatial distribution of the gas luminescence energy. © 2015, Pleiades Publishing, Ltd.
Laricheva V.V.,Zhukovskii Central Aerohydrodynamic Institute
Doklady Physics | Year: 2011
A study was conducted to demonstrate analytical solutions and singularities of evolution equations of the orbit of a spacecraft under the action of small forces. Adequate asymptotic forms were proposed for solutions entering into the composition, leading to a sufficient accuracy of the analytic representation of the general solution describing that a multiturn spacecraft (SC) trajectory was reached. The practical application of an algorithm showed that the satisfactory accuracy was reached in the second approximation when n + 1 = 2. The possibility of the obtainment of the analytical representation that was sufficiently accurate at the change of φ in the interval of the order of 1/ε in the whole smallness region of perturbation terms and single for values of eccentricity less than unity up to zero was shown for the general solution as a result.
Kucherov A.N.,Zhukovskii Central Aerohydrodynamic Institute
Technical Physics | Year: 2015
A crisis caused by an external force (deceleration of the flow down to the radial Mach number equal to unity) is studied in the regime of vortex source flowing into vacuum. The dependences of the critical characteristics (critical radius, temperature, and velocity) on the gas circulation Γ is studied in two situations: at a constant external force distribution function and at a constant pressure in the zone of action of the force. It is shown that the adiabatic relation between the pressure, temperature, and density is valid. Explicit analytic solutions inside the zone for Γ = 0 and implicit solutions for Γ > 0 are obtained. In the case of a uniform distribution of the external force, it is found that the effect of the integral of force (work) on the critical characteristics dominates and is independent of the initial parameters (zone coordinate, temperature at the inlet, etc.). In the case of constant pressure, the regions of realization of the crisis in the space of the similarity numbers (force, circulation, and initial coordinate and temperature) are plotted. © 2015, Pleiades Publishing, Ltd.
Bashkin V.A.,Zhukovskii Central Aerohydrodynamic Institute |
Egorov I.V.,Zhukovskii Central Aerohydrodynamic Institute |
Ezhov I.V.,Zhukovskii Central Aerohydrodynamic Institute
High Temperature | Year: 2016
The results of numerical simulation of transonic cross flow of a perfect gas around a circular cylinder at high Reynolds numbers are used to solve the thermal problem. The temperature distributions along the central line and the influence of Reynolds and Mach numbers on them are presented. The temperature fields and the transition of the near-wake solution to the far-wake solution are studied. © 2016, Pleiades Publishing, Ltd.