V.A. Makrygina
Vinogradov Institute of Geochemistry, Siberian Branch of the Russian Academy of Sciences, ul. Favorskogo 1a, Irkutsk, 664033, Russia
Keywords: Geochronology, geochemistry, geophysics, metasedimentary and igneous rocks, frontal and oblique collision, subduction, strike-slip tectonics, melt interaction, Ol’khon-Khamar-Daban terrane
Analysis of geochemical, geochronological, and new geophysical data on metasedimentary and igneous rocks of the Ol’khon region has made it possible to substantiate: (1) the absence of products of the Caledonian suprasubduction magmatism from the adjacent part of the Siberian craton and (2) the presence of a product of this magmatism in the Anga-Talanchan island arc, namely, the Krestovsky massif with gabbrodiorite to granite phases. This suggests subduction of the Paleoasian oceanic crust under the island arc before the collision. The geophysical data showed a steep sinking of the Siberian craton margin. This sinking and the supposed contrary movement and rotation of the Siberian craton prevented the appearance of a subduction zone beneath the craton during the collision but caused the wide development of fault plates in the fold belt at the late collision stage. The residue of oceanic crust slab was pressed out along the fault planes near the surface and formed a row of gabbro-pyroxenite massifs of the Birkhin Complex in the fold belt, where syncollisional granitic melts (Sharanur Complex) formed at the same time. The interaction of two contrasting melts gave rise to the Tazheran and Budun alkaline syenite massifs and alkaline metasomatites of the Birkhin and Ulanganta gabbroid massifs.
I.S. Novikov1, D.A. Borisenko2 1V.S. Sobolev Institute of Geology and Mineralogy, Siberian Branch of the Russian Academy of Sciences, pr. Akademika Kopyuga 3, Novosibirsk, 630090, Russia 2Novosibirsk Geological Exploration Expedition, ul. Borovaya Partiya 12, Novosibirsk, 630116, Russia
Keywords: Planation surfaces, geomorphology, neotectonics, marine terraces, Crimean Mountains
The area of southwestern Crimea includes the ending of the Crimean Mountains that arose during the neotectonic activation at the place of the Cretaceous-Paleogene denudation plain and the adjacent shallow-water carbonate sedimentation basin. The Crimean Mountains are one of the links of the Alpine-Himalayan orogenic belt formed during the collision of the Eurasian, African, and Indo-Australian plates. Their area includes late Cenozoic marine terraces of the complete Mediterranean series and a staircase of Neogene, Paleogene and Cretaceous planation surfaces over them. The planation surfaces of different ages resulted from the successive lowering of the World Ocean level. Their subsequent deformations make it possible to outline the area of the neotectonic uplifting and determine its parameters. The main mechanism of the neotectonic activation was the thrust of the East Black Sea microplate under the Scythian one and the formation of a ramp fold structure. The amplitude of the neotectonic uplifting of southwestern Crimea for the past 2 Myr varies from 0 to 800 m, i.e., is up to 0.04 mm/year. The recent neotectonic structure of the area is formed by the northern flank of the ramp fold; it is a monocline of NW dip consisting of “keys” of NW strike separated by the latest faults with vertical displacements of 10 to 120 m. The uplifting of the area and the lowering of the World Ocean level led to a wide spread of denudation surfaces. Their good preservation makes it possible to refine the sequence of neotectonic events, whose first pulses reached the study area in the Oligocene, and the main activation phase began in the Pliocene.
E.I. Lastochkin1, G.S. Ripp1, D.S. Tsydenova1, V.F. Posokhov1, A.E. Murzintseva2 1Geological Institute, Siberian Branch of the Russian Academy of Sciences, ul. Sakh'yanovoi 6a, Ulan-Ude, 670047, Russia 2Buryat Scientific Center, Siberian Branch of the Russian Academy of Sciences, ul. Sakh'yanovoi 8, Ulan-Ude, 670047, Russia
Keywords: Fluorite, pyrite, barite, quartz, isotopy, fluid, Transbaikalia
We consider the isotope-geochemical features of epithermal fluorite deposits in Transbaikalia, including the REE compositions, Sr isotope ratios, Sm-Nd systems, and isotope compositions of oxygen, carbon, hydrogen, and sulfur. The 87Sr/86Sr values in fluorites are within 0.706-0.708, and the εNd values are negative. Oxygen in quartz, the main mineral of the deposits, has a light isotope composition (δ18O = -3.4 to +2.6 ‰), and the calculated isotope composition of oxygen in the fluid in equilibrium with quartz (δ18O = -9 to -16 ‰) indicates the presence of meteoric water. The latter is confirmed by analysis of the isotope compositions of oxygen and hydrogen in gas-liquid inclusions in fluorites from three deposits. These isotope compositions are due to recycling caused by the impact of shallow basic plutons. The isotope composition of sulfur indicates its deep source. During ascent, sulfur became enriched in its light isotope (δ34S = -1.8 to -7.7 ‰). We assess the association of fluorite ores with basaltoids widespread in the study area. The isotope and geochemical parameters suggest their spatial proximity. Probably, the basaltoids were responsible for the recycling of meteoric water. It is shown that the epithermal fluorite deposits formed by the same mechanism as fissure-vein thermal waters in western Transbaikalia.
A.Y. Barkov1, E.V. Sharkov2, A.A. Nikiforov1, V.N. Korolyuk3, S.A. Sil'yanov4, B.M. Lobastov4 1Cherepovets State University, pr. Lunacharskogo 5, Cherepovets, 162600, Russia 2Institute of Geology of Ore Deposits, Petrography, Mineralogy and Geochemistry, Russian Academy of Sciences, Staromonetnyi per. 35, Moscow, 119017, Russia 3V.S. Sobolev Institute of Geology and Mineralogy, Siberian Branch of the Russian Academy of Sciences, pr. Akademika Koptyuga 3, Novosibirsk, 630090, Russia 4Institute of Mining, Geology and Geotechnologies of Siberian Federal University, pr. Imeni Gazety Krasnoyarskii Rabochii 95, Krasnoyarsk, 660025, Russia
Keywords: Compositional variations of apatite, REE minerals, behavior of volatiles, mineralogical and geochemical crystallization trends, Monchepluton layered complex, layered intrusions, mafic-ultramafic complexes, Kola Peninsula, Fennoscandian Shield
We have investigated the compositional variations of apatite (Ap) and rare-earth element (REE) minerals in the Monchepluton layered complex on the Kola Peninsula. On the basis of large sets of pertinent analytical data, we have estimated geochemical trends involving major, minor, and trace elements and studied their relation with the compositions of rock-forming silicate and oxide minerals. The variations observed in Ap differ considerably from trends reported for other layered intrusions. The composition fields of Ap are not consistent with the variations in the chemical composition of the bulk rocks and their constituent minerals, as determined along the representative cross sections of the entire complex. The compositional variations of Ap are fairly similar in all units of the complex. Chlorapatite (>6 wt.% Cl) is invariably abundant. There is no relationship between the Cl content of Ap and the degree of magnesium enrichment of the coexisting early magmatic silicates. In the F-Cl-OH diagram, broad fields of ternary solid solution are observed. There are no compositions along the Cl-F axis. The compositions of Ap are notably poor in Cl in the marginal series (the Nyud massif) and correspond to hydroxylapatite with a high content of fluorapatite component. Two composition fields of Ap are recognized in the Monchepluton complex: ≤3 wt.% and >6 wt.% Cl; there are, however, extensive overlaps. Two generations of apatite are thus implied. The first nucleated at the early stage of crystallization of H2O-bearing intercumulus melt as a result of substantial increase in the contents of P, F, Cl, and other incompatible components. The following stage of degassing of the crystallizing melt caused a decoupling of Cl and F. Fluorine remained mostly in the melt; in contrast, Cl was partitioned efficiently into an H2O-bearing fluid phase. At the early stage, the apatite incorporated combinations of hydroxylapatite and fluorapatite, with a low content of Cl. At the late stage, chlorapatite crystallized from a Cl-rich fluid, and ferrochloropargasite (4.1 wt.% Cl) formed in the Poaz massif as a result of autometasomatic alteration via reactions of this fluid with plagioclase and pyroxene. The apatite has high Sr contents (up to 4.1 wt.% SrO) in the highly magnesian cumulates of the Dunite block and the massifs of mounts Kumuzh’ya, Nittis, and Travyanaya. This enrichment illustrates the accumulation of Sr in the intercumulus melt, in which Ap was the only Sr-bearing phase in the absence or scarcity of intercumulus plagioclase. The REE contents also increased in the intercumulus melt and led to the formation of monazite-(Ce), REE-bearing Ap, and allanite-(Ce) in the remaining microvolumes of melt. Loveringite and Ap crystallized as coexisting phases in Mt. Sopcha. For the first time in a layered intrusion, an extensive range of compositions is documented in the Ce-La-Nd diagram for the REE-bearing phosphates (monazite and REE-rich apatite), which display a predominant La ↔ Nd substitution at the constant contents of Ce.
A.N. Berzina, A.P. Berzina, V.O. Gimon
V.S. Sobolev Institute of Geology and Mineralogy, Siberian Branch of the Russian Academy of Sciences, pr. Akademika Koptyuga 3, Novosibirsk, 630090, Russia
Keywords: Porphyry Cu-Mo deposits, ore-bearing magmatism, geochemistry and isotope geochemistry, Aksug, Tuva
Two stages are recognized in the evolution of the Aksug ore-magmatic system (OMS): (1) formation of the Aksug granitoid pluton and (2) emplacement of small ore-bearing intrusions. Intrusive bodies of the two stages are composed of rocks of the same type and bear copper mineralization: poor dispersed and large-scale veinlet-disseminated, respectively. The pluton and small intrusions are formed by gabbroid and granitoid rocks, with similar petrogeochemical characteristics of igneous rocks of the same type. The plutonic gabbroic association includes gabbro, gabbrodiorites, and pyroxene-amphibole diorites/quartz diorites. The small subvolcanic gabbroic intrusions are gabbrodiorite and diorite porphyrites. The trace element patterns of the gabbroids are similar to those of igneous rocks in subduction zones. The gabbroids are characterized by isotope parameters εNd(500) = +6.1 to +7.2 and (87Sr/86Sr)500 = 0.7022-0.7030 and model age TNd(DM) = 0.85-0.74 Ga. As follows from the geochemical parameters, the depleted mantle metasomatized by subduction fluids was the source of basaltic magma. The plutonic granitoid association includes tonalites, plagiogranites, and amphibole diorites/quartz diorites; the small subvolcanic granitoid intrusions are tonalite porphyry and quartz diorite porphyrites. The trace element patterns and Nd and Sr isotope compositions of the granitoids are much similar to those of the gabbroids. According to the geochemical parameters, tonalitic and plagiogranitic magmas formed through the melting of juvenile mafic crust, and dioritic magma resulted from the mixing of basaltic and tonalitic/plagiogranitic magmas. In the course of the OMS formation, metals and volatiles were introduced by basaltic and granitoid magmas from the metasomatized mantle and juvenile mafic crust. The compression setting during the pluton formation hampered the separation of ore-bearing fluids, which led to poor dispersed mineralization. The extension setting during the emplacement of small intrusions favored the intense separation of ore-bearing fluids. The interaction of magma and fluids of the small intrusions with rocks of the pluton was accompanied by the removal of metals from the latter and their involvement in the ore-forming process. This increased the ore potential of the magmatic system and favored the formation of rich mineralization at the final stage of its evolution.
The main factors controlling the bulk sedimentation in the region of the Siberian segment of the Lomonosov Ridge (axial part and western slope) and the Laptev Sea continental margin during the late Cenozoic were studied using a complex of geomorphological, lithological, and organic geochemical data. Samples for the study were collected during the cruises of R/V Akademik Fedorov in 2005 and 2007 and nuclear icebreaker Rossiya in 2007. Analysis of the group and molecular composition of the dispersed organic matter (DOM) in bottom sediments has shown that the input of terrigenous sediments enriched in the products of abrasion of lithified rocks determines sedimentation process on the continental slope of the Laptev Sea and in the Amundsen Basin. The individual characteristics of the DOM of the late Cenozoic sediments from the Lomonosov Ridge reflect the wide diversity of sedimentary sources and depositional environments. Subaqueous erosion of edaphogenic products and pre-Holocene sediments play an important part in sedimentation together with terrigenous flow and ice transport.
E.V. Pospeeva, V.V. Potapov
Trofimuk Institute of Petroleum Geology and Geophysics, Siberian Branch of the Russian Academy of Sciences, pr. Akademika Koptyuga 3, Novosibirsk, 630090, Russia
Keywords: Magnetotelluric studies, geoelectric horizons, neotectonic faults, conductive heterogeneous beds, electrical resistivity, Gorny Altai
Results of magnetotelluric studies (MTS) carried out along SW-NE and W-E profiles across the Chuya depression are used to demonstrate the deep geoelectric structure of its internal field and the transition zones to northern (Kurai Ridge) and southern (South Chuya Ridge) mountainous frames. The Chuya depression is an area with small-block structure, with its axial part comprised of the thinnest (450-650 m) sedimentary deposits. The key sites of the transition zones from this depression to the Kurai Ridge and the South Chuya Ridge manifest a complete geoelectric section of sedimentary deposits with a total thickness of 1000-1200 m. Subvertical conductive heterogeneous beds of abnormally low (<5 Ohm·m) specific resistivity are mapped in the section of the sedimentary cover and the Paleozoic basement. They mark neotectonic faults and the their intersection nodes with the Paleozoic and Mesozoic faults. The kinematic parameters of the faults determined from the magnetotelluric data are generally consistent with the data of morphotectonic and geological studies.
G.V. Reshetova1, A.V. Anchugov2 1Institute of Computational Mathematics and Mathematical Geophysics, Siberian Branch of the Russian Academy of Sciences, pr. Akademika Lavrentieva 6, Novosibirsk, 630090, Russia 2AO Geologika, ul. Musy Dzhalilya 23, Novosibirsk, 630055, Russia
Keywords: Core, rock mechanical tests, acoustic emission, simulation, time reversal mirror
Acoustic-emission events in core samples are detected from total wave energy by time reversal mirror (TRM) inversion using equations of the elastodynamic theory in polar coordinates. The acoustic emission parameters used in the modeling correspond to laboratory testing data on core samples. The simulation results for digital core have implications for the configuration of multichannel data acquisition, including the optimal number of receivers or channels and the placement of sensors. Testing with different numbers of receivers/channels and at different frequencies shows that the method can provide satisfactory resolution even at a relatively low frequency.
A.D. Bykov, B.A. Voronin, A.S. Dudaryonok, E.R. Polovtseva
V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, Tomsk, Russia
Keywords: isotopic shift of vibrational levels, Rayleigh-Schrodinger perturbation theory, summation of divergent series of perturbation theory
High-order Rayleigh-Schrodinger perturbation theory and series summation by the Pade-Hermit approximants are used to calculate the vibrational energy levels of isotopically substituted molecules. As an example, the levels of water isotopologues are calculated. It is found that the perturbation series diverge in the cases of both hydrogen by deuterium or tritium substitution and "heavy" oxygen atom (O16->O18) substitution. However, the use of the Pade-Hermit approximants makes it possible to calculate the isotopic level shifts quite accurately for any isotope substitution, both preserving the symmetry of the molecule and reducing it.
V.I. Starikov1, S.N. Mikhailenko2 1Tomsk State University of Control Systems and Radioelectronics, Tomsk, Russia 2V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, Tomsk, Russia
Keywords: ozone molecule, spectral line broadening, nonpolynomial representation
The parameters of a nonpolynomial analytical model γ (sur) are determined from the fitting of the known experimental data on the N2-, O2-, air-, and self-broadening coefficients of the ozone absorption lines. The model gives a finite value for the coefficients γ in asymptotic. The average accuracy of experimental data description is better than 3% for several thousand lines with quantum numbers up to J = 60. The results of the calculations based on the model suggested are compared to the results obtained using polynomial representations for the broadening coefficients.
L.A. Bolbasova, V.P. Lukin
V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, Tomsk, Russia
Keywords: adaptive optics, atmospheric optical turbulence, site testing, measurement methods
Adaptive optics (AO) systems are an essential part of large astronomical telescopes and laser complex operating through the atmosphere. Each AO system is individually designed; the requirements for the elements and the capabilities of an AO system are determined by the intensity and distribution of turbulent fluctuations of the air refractive index over the radiation propagation path. In this paper, we overview the techniques and means for measuring and forecasting atmospheric conditions for AO problems, including those developed at IAO SB RAS. The basic principles of atmospheric adaptive optics and the atmospheric parameters used are briefly described. Particular attention is paid to the parameter introduced for estimating usability of AO systems, i.e., the wind speed at a level of 200 hPa; the comparison with the data from foreign astronomical observatories is carried out. The need in atmospheric research for large Russian astronomical observatories is discussed.
I.D. Bryukhanov1,2, S.V. Zuev3, I.V. Samokhvalov1 1National Research Tomsk State University, Tomsk, Russia 2V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, Tomsk, Russia 3Institute of Monitoring of Climatic and Ecological Systems of the Siberian Branch of the Russian Academy of Sciences, Tomsk, Russia
Keywords: high-level clouds, anomalous backscattering, oriented ice crystals, polarization lidar, backscattering phase matrix, zenith pyranometer, diffuse solar radiation
The technique and results of a complex experiment on studying the effect of high-level clouds (HLCs) on the scattered solar radiation flux are described. The optical characteristics (scattering ratio, optical depth, and backscattering phase matrix) and geometric characteristics (the lower and upper boundary altitudes and vertical thickness) of clouds were estimated based on the lidar data, and the scattered solar radiation flux in the zenith direction was measured with a pyranometer. It is shown that specular HLCs, i.e., consisting of preferably horizontally oriented ice crystals, significantly reduce the fluxes of scattered solar radiation incident on the Earth’s surface in comparison with HLCs with approximately the same optical depth, but with chaotically orientated particles.
S. G. Mironov1,2, S. V. Kirilovskiy1,2, T. V. Poplavskaya1,2, I. S. Tsyryulnikov1,2 1Khristianovich Institute of Theoretical and Applied Mechanics, Siberian Branch, Russian Academy of Sciences, Novosibirsk, 630090 Russia 2Novosibirsk State University, Novosibirsk, 630090 Russia
Keywords: supersonic flows, flow control, porous gas-dynamic inserts, drag
Results of experimental and numerical investigations of a supersonic flow of cylindrical models aligned at a zero angle of attack with frontal inserts made of cellular-porous nickel are reported. The experiments are performed in a supersonic wind tunnel at Mach numbers M¥= 4.85 and 7.00 and unit Reynolds numbers Re1 = 2.7 x 106 and 1.5 x 106 m-1, respectively. Numerical simulations with the use of a ring-shaped skeleton model of the porous material are also performed. A possibility of drag control is studied for two thermal methods: external heating of the porous insert and internal heating of the insert by a glow discharge. The mechanisms of the thermal action and the efficiency of the thermal methods of drag control are analyzed.
Results of experimental and numerical investigations of walls reinforced with steel fibered concrete panels are reported. Eighteen walls produced by using hollow bricks and aerated concrete are studied in experiments; these walls are strengthened with concrete panels produced by using steel fibers at certain ratios. Six unreinforced reference specimens are also tested. Load-displacement curves are derived, the maximum stresses and displacements are determined, and the cracking process is studied. The experimental results are compared with those obtained from modeling.
Yu. V. Pivovarov
Lavrent'ev Institute of Hydrodynamics, Siberian Branch, Russian Academy of Sciences, Novosibirsk, 630090 Russia
Keywords: incompressible fluid, Navier-Stokes equations, slip condition, weak boundary layer, vorticity, stream function
A problem related to the plane-parallel steady motion of a low-viscosity incompressible fluid that fills half a rotating cylindrical cavity is under consideration. The Navier slip condition is imposed on the fluid - solid wall interface, and the condition for the absence of tangential stresses is imposed on the free boundary. The equation of the boundary layer considered on the entire boundary of the semicircle as a whole is reduced to a heat conduction equation by changing the variable. The solution to the problem is constructed in the form of a series, while the corner boundary layers are ignored. Calculations and comparisons with the solution built earlier using the finite difference method are performed.
S. A. Kinelovskii
Lavrent'ev Institute of Hydrodynamics Siberian Branch, Russian Academy of Sciences, Novosibirsk, 630090 Russia
Keywords: polymorphism, shock wave, quartz, coesite, stishovite, phase transition
This paper presents a model that links the polymorphic transformation of a crystalline substance under shock-wave loading with a change in its elastic energy. The complete and partial transformation of the substance in the shock front and the conditions for the occurrence of this transformation are determined. The model was tested by describing polymorphic transition in non-porous pyrolytic graphite and transitions in the silicon dioxide system. It is shown that the model satisfactorily describes available experimental results.
E. M. Nurullaev
Perm National Research Polytechnic University, Perm, 614990 Russia
Keywords: polymer composite material, permittivity, dielectric loss tangent, heating temperature, microwave radiation, absorbed thermal energy density
This paper presents the results of experimental determination of electrophysical characteristics such as the permittivity and dielectric loss tangent of plasticized three-dimensionally cross-linked and filled with solid dispersed fillers of polymer composite material on based on low molecular weight rubbers. The measurement technique is described and the experimental results are analyzed. The dependence of the thermal energy density absorbed by the investigated material on the time of exposure to ultrahigh-frequency radiation is calculated.
S. Syahrul, M. Mirmanto, S. Sukmawaty, G. Putra, S. As'ary
Mataram University, 83125, Mataram, Indonesia
Keywords: paddy mass, drying rate, efficiency, vertical dryer
An experimental study of a novel dryer is performed. In this current study, paddy drying is carried out using a vertical dryer. The paddy mass is varied as 10, 20, and 30 kg at the air temperature and velocity of 60oC and 5 m/s, respectively. The results indicate that an increase in the paddy mass raises the drying rate and efficiency. However, the large masses of paddy need a long time to reach the required 14% moisture content. The highest efficiency achieved is 3.27% at the paddy mass of 30 kg.
S. D. Algazin1, I. A. Selivanov2 1Ishlinsky Institute for Problems in Mechanics, Russian Academy of Sciences, Moscow, 119526, Russia 2Moscow State University, Moscow, 119991, Russia
Keywords: biharmonic equation, free vibrations of a plate, method Bubnova-Galerkina, computational experiment
Natural vibrations of a rectangular plate with two pinched and two freely supported edges. The Bubnov method - Galerkin methods are used to obtain the first eigenvalues, and one of the test functions has its first eigenvalue calculated with an error smaller than 1%. Comparison with known results is carried out, with eigenforms given.
A. S. Vereshchagin1,2,3 1Khristianovich Institute of Theoretical and Applied Mechanics, Siberian Branch, Russian Academy of Sciences, Novosibirsk, 630090 Russia 2Novosibirsk National Research State University, Novosibirsk, 630090 Russia 3Novosibirsk State Technical University, Novosibirsk, 630073 Russia
Keywords: composite sorbent, helium, water vapor, microspheres, membrane sorption method
Within the framework of multiphase media mechanics, a mathematical model of gas mixture dynamics is obtained, including helium and water vapor, in a layer of resting composite sorbent based on microspheres and a porous matrix of moisture absorber made of aluminum oxide. The study is carried out with account for the law of conservation of momentum with account for the force of resistance to the layer, described by the Forchheimer filtration relations, and the law of conservation of energy within the framework of a single-temperature non-heat-conducting models.
G. Yu. Evtushok1, A. V. Boiko1, S. N. Yakovenko1, E. E. Yakovenko1, K. C. Chang2 1Khristianovich Institute of Theoretical and Applied Mechanics, Siberian Branch, Russian Academy of Sciences, Novosibirsk, 630090 Russia 2National Cheng Kung University, Tainan, 70101 Taiwan
Keywords: dam-break flow, water column, wave front, free surface, volume fraction, surface tension, turbulence models, computational fluid dynamics
Numerical simulation of dam-break water flow over a horizontal dry bottom was performed. Computational technologies including methods for determining the position of the interface and the continual model of the surface tension force implemented in PIFI code, and OpenFOAM software package with interFoam solver and various versions of the two-parameter (κ-ε)-model with adjustments made taking into account the behavior of flows in areas with small Reynolds numbers were modified and verified. Calculated integral characteristics of dam-break flow were analyzed and compared with measured data. It is shown that taking into account the surface tension and using an adequate turbulence model leads to deceleration of water movement and hence to a decrease in the speed of the wave front, resulting in better agreement between the results of calculations and laboratory experiments.
J. Ma1, Z. H. Chen2, D. W. Xue3, X. H. Sun4, R. Liu1 1Nanjing Tech University, Nanjing, Jiangsu, 211816, China 2Nanjing University of Science and Technology, Nanjing, Jiangsu 210094, China 3Zhejiang Ocean University, Zhoushan, Zhejiang, 316022 China 4Shanghai Aerospace Control Technology Institute, Shanghai, 201109 China
Keywords: aerodynamics, microvortex generator jet, flow separation control, spinning projectile
The possibility of using microvortex generator jets to improve the flight stability and firing accuracy of the M549 projectile by regulating the vortex distribution on the surface is studied in this paper. The microvortex generator jet is inserted in front of the projectile shoulder, and the flow field structure around the projectile is simulated by the detached eddy simulation method. The numerical results show that microvortex generator jets can eliminate irregular vibrations induced by aerodynamics forces by inhibiting vortex shedding.
I. N. Soldatov1,2, N. V. Klyueva1,2 1Institute of Applied Physics, Russian Academy of Sciences, Nizhny Novgorod, 603950, Russia 2Lobachevsky Nizhny Novgorod State University, Nizhny Novgorod, 603022, Russia
Keywords: floating viscous fluid, azimuthal inertial (gyroscopic) waves in a centrifuge, dispersion equation
Azimuthal gyroscopic waves in a floating liquid forming a centrifuged layer on the solid wall of a cylindrical rotor cavity are studied. The exact solution of the linearized hydrodynamic problem with a nonclassical boundary condition on the free surface is obtained. The dispersion equation is derived. The influence of the inertial surface of the liquid on stability of quasi-solid rotation of the centrifuged layer is studied.
According to the dynamic model of the vehicle starting process and the theory of heat transfer, a clutch temperature field model under different starting conditions is established based on the time-varying characteristics of the convective heat transfer coefficient of the flow field. The effects of the engine target speed, clutch engagement pressure change rate, and road gradient on the temperature field distribution are revealed. The results of the study are compared with those obtained earlier by the finite element method.
M. Sajid, M. Rooman, N. Ali, M. N. Sadiq
International Islamic University, Islamabad, 4400 Pakistan
Keywords: Ellis fluid, renal tubule, creeping flow, axisymmetric flow
The flow of the Ellis fluid in the renal tubule is investigated in this paper. The fluid absorption at the wall is influenced by the pressure gradient across the wall and by the permeability of the wall. The governing equations are considerably simplified if the tubule radius is assumed to be much smaller than its length. Important quantities of interest are computed numerically. The results are compared with available data and are found to be in good agreement.
P. V. Krauzin, M. T. Krauzina
Perm State National Research University, Perm, 614990, Russia
Keywords: colloidal solution, spherical cavity, concentration distribution
A problem of sedimentation-induced concentration convection in a spherical cavity is considered. It is shown, that the flow is formed due to concentration inhomogeneity near the surface and has the form of two tori, and the convection leads to acceleration separation of the mixture.
A. V. Voevodin, A. A. Kornyakov, A. S. Petrov, D. A. Petrov, G. G. Soudakov
Central Aerohydrodynamic Institute named after Prof. N. E. Zhukovsky, Zhukovsky, 140180, Russia
Keywords: rectangular wing, transonic buffet, separated flow, ejector, spectral analysis
A problem of the flow around a rectangular wing under the transonic buffer conditions in a wind tunnel is investigated numerically and experimentally. It is shown that a three-dimensional flow with a “mushroom” structure of the surface streamlines on the wing surface is formed instead of a close-to-two-dimensional flow in the case with self-excited oscillations along the streamwise coordinate (buffet). For the purpose of buffet control, an ejector is proposed, which provides boundary layer suction from the upper surface of the wing and jet ejection at the trailing edge of the wing. The spectral analysis of the experimental pressure oscillations on the upper surface of the wing shows that the proposed device effectively suppresses pressure oscillations at the buffet frequency.
R. F. Sharafutdinov, F. F. Davletshin
Bashkir State University, Ufa, 450076 Russia
Keywords: thermometry, hydraulic fracture crack, Joule-Thomson effect, adiabatic effect, well, formation
The paper considers the results of calculating non-stationary pressure and temperature fields in a low-permeable reservoir with a hydraulic fracturing crack, taking into account the thermodynamic (Joule-Thomson and adiabatic) effects. The influence of the crack parameters (width and permeability) on the nature of the time variation in the temperature of the fluid flowing into the well is analyzed. It is shown that an increase in the pressure gradient in the crack with decreasing crack width and permeability enhances the Joule-Thomson effect. As a consequence, the temperature of the flowing liquid increase over time and the adiabatic cooling effect begins to prevail with increasing width and permeability of the crack, resulting in decrease in the temperature of the supplied fluid. The obtained features of the temperature field can be used in the diagnostics of hydraulic fracture parameters.
M. Pang, C. W. Jin, Y. Q. Zhang
Zhejiang University, Hangzhou, 310058, China
Keywords: thick-walled cylindrical vessel, burst failure, plastic anisotropy, strain hardening
The analysis of the burst failure of a thick-walled cylindrical pressure vessel with plastic anisotropy under the action of internal and external pressures is carried out. Theoretical solutions for the burst pressure and the corresponding equivalent strain for the thick-walled cylindrical pressure vessel with ends closed are derived. The effects of plastic anisotropy, strain hardening, and external pressure on burst failure are discussed. The results show that the burst pressures for close-ended thick-walled cylindrical pressure vessels are dependent upon plastic anisotropy and external pressure, while the corresponding equivalent strains are only dependent upon plastic anisotropy, and the degree of the dependence is related to the strain hardening exponent of the material and on the ratio of the outer radius to inner radius of the vessel.
S. V. Pogudalina, N. N. Fedorova
Khristianovich Institute of Theoretical and Applied Mechanics, Siberian Branch, Russian Academy of Sciences, Novosibirsk, 630090, Russia
Keywords: aeroelasticity, conjugate problems, interaction of flows with structures, wind effects, numerical modeling, flow structure, vortex Karman track, resonance
This study touches upon a numerical simulation of vibrations of an elastic rod whose height is significantly greater than the transverse dimension and which is installed perpendicular to the external flow and rigidly fixed to the substrate. Modeling is performed in the ANSYS software complex using bi-directional technology pairing. Eigen-frequencies and vibrations modes of the rod are calculated. The structure is analyzed and the features of the flow are described. The process of excitation of vibrations of an elastic rod under the action of an external flow is investigated and its stress-strain state is determined. The vibration modes in the direction of the incident flow and in the transverse direction are determined. It is shown that at close values of the first natural frequency and the frequency of vortices descent, the amplitude of the rod oscillations in the transverse direction sharply increases to a value approximately equal to 0.06 of the rod height, after which a self-oscillating mode is established with a constant amplitude in the transverse direction and variable amplitude in the direction of the incident flow.
A. A. Kozhemyachenko1,2, I. B. Petrov1,2, A. V. Favorskaya1,2 1Moscow Institute of Physics and Technology, Dolgoprudny, 141701, Russia 2Research Institute of System Analysis, Russian Academy of Sciences, Moscow, 117218, Russia
Keywords: grid-characteristic method, numerical modeling, wheel-rail system, wave phenomena, railway track
The damage to a railway during high-speed movement of heavy trains in its various sections is modeled using a grid-characteristic method in the case of structured grids the damage process. The separation of sleepers from the ballast layer is studied. Computer simulation provided various wave patterns and patterns of dynamic distributions of the Cauchy stress tensor (pressure) components during train movement on a railway track. The cracking process is described.
On the basis of the analysis of a large array of experimental data on average heat transfer and hydraulic resistance, calculations of the dynamic velocity on the wall in deep rows of in-line and staggered tube bundles transversely streamlined by the turbulent flow of the coolant are performed. In addition, energy consumption is calculated based on experimental data on the hydraulic resistance of rod assemblies. The obtained results serve to determine the coefficient of proportionality between the dynamic velocity and the energy consumption for pumping the coolant. The proposed calculation formulas for the proportionality coefficient allow computing the average heat transfer coefficient in transversely streamlined in-line and staggered tube bundles in a wide range of rod packing spacings and Reynolds numbers, using the universal dependence of heat transfer on dynamic velocity.
The article presents the results of studies of the coolant flow in fuel assemblies behind the intensifier grids of FA-Square reactors of the PWR type. The aim of this work is to evaluate the effectiveness of using various designs of the intensifier grid for the flow mixing. To achieve this goal, a number of experimental studies are carried out on an aerodynamic stand with scale models of fragments of fuel assemblies with intensifier grids of various designs. Adjacent cells of the guide channel, the design feature of which is different spatial orientation of turbulators installed on the intensifier grids, are selected as a representative area of research. The general flow pattern is represented by vector fields of tangential velocities, as well as by graphical dependences of the distribution of transverse velocities in the gaps between the rods of the research area. To evaluate the efficiency of using various intensifier grids’ designs for the coolant flow mixing, the parameters of intracellular vortex formation and intercellular mixing are analyzed. Analysis of the spatial distribution of tangential flow velocities allows studying and detailing the coolant flow pattern behind the mixing grids with various designs of deflectors. The accumulated database on the coolant flow in the FA-KVADRAT is the basis for engineering justification of the PWR reactor core designs. The results of experimental studies are used to verify CFD codes of both foreign and domestic development, as well as programs for detailed cell-based calculation of active zones in order to reduce conservatism in justifying thermal reliability.
In the present study, a numerical investigation was conducted to enhance the film cooling efficiency by using anti-vortex designs. Four configurations are considered in this paper, which are the configuration with the streamwise cylindrical injection, the case with an upstream Barchan dune shape ramp (BDSR), the case with sister holes and the configuration that combine the Barchan dune shape with sister holes. The effects of a blowing ration (M = 0.5, 0.85, 1.0 and 1.5) on the film cooling effectiveness are considered. The validation shows good agreement and almost all flow structures are well reproduced by the RANS computation. Results show that the Barchan dune shapes with sister holes have an influence on thermal and flow structures, this configuration substantially augments the film cooling efficiency.
N.A. Dvornikov, V.V. Lukashov, R.Kh. Abdrakhmanov
Kutateladze Institute of Thermophysics SB RAS, Novosibirsk, Russia
Keywords: vortex chamber, centrifugal fluidized bed, particle entrainment from the chamber
The conclusions about the nature of bed fluidization and the rate of polyfractional material entrainment in the cylindrical vortex chamber with the air supply through the lower and upper end swirlers were drawn, based on visual observation of the fluidized bed, determination of entrainment of the bed dispersed material by weighing the material after a given time of vortex chamber operation, and also by means of numerical simulation of dynamics of the fluidized bed of particles.
The results of an experimental study of a bubble diameters variation with a distance from the gas injection point in an upward bubbly flow in an inclined flat channel are presented. The measurements were carried out for a superficial liquid velocity of 0.51 m/s (Re = 12400) and various volumetric gas flow rate ratios. It is shown that at low values of volumetric gas flow rate ratio ( β < 2 %) there is almost no bubble coalescence; therefore, the channel inclination angle and distance from the point of gas injection into the liquid flow do not affect the average diameter of gas bubbles.
V.V. Datsenko, Yu.A. Zeigarnik, E.O. Kalashnikova, A.A. Kosoy, A.S. Kosoy, M.V. Sinkevich
Joint Institute for High Temperatures RAS, Moscow, Russia
Keywords: power plant, combined cycle plant without compressor, thermal efficiency, capturing of СО in liquid state, combined production of power and heat
The energy security of Russia is at threat due to recent trends of dependency of national power industry on imported technologies, equipment, spare parts and materials. The next challenge is a tendency of more strict environmental standards and restrictions for power generation equipment. The paper considers one option to meet those challenges - using technologies based on compressorless combined cycle plant with complete capturing of СО2 in liquid state (developed by JIHT in cooperation with NPO Almaz). This technology offers efficient production of heat and power from hydrocarbon fuel with a minimal environmental impact. This plant can be incorporated into a power-engineering complex with chemical products outcome. According to the developed scheme, the hydrocarbon fuel is burnt in a mixture of oxygen, provided by an air-separation setup (or another source), steam and carbon dioxide. The components are compressed in the liquid phase. The heat from exhaust gas is recuperated in a developed heat recovery system. The steam condensation takes place, and the heat of condensation is utilized for district water heating in water utility grids and for capturing of СО2 in liquid phase. Through varying of proportions between Н2О and СО2 inputs, the proportions in generation of electric power and heat can be varied in a wide range. Our estimates demonstrate that this new plant has a thermal efficiency higher than for the best CCGT plants and close to the efficiency for the best worldwide analogs.
A.S. Surtaev1,2, V.S. Serdyukov1,2, I.P. Malakhov1,2, M.V. Timoshevskiy1,2, A.S. Safarov1,3 1Novosibirsk State University, Novosibirsk, Russia 2Kutateladze Institute of Thermophysics SB RAS, Novosibirsk, Russia 3Melentiev Energy Systems Institute SB RAS, Irkutsk, Russia
Keywords: pulsed heating, boiling, subcooled liquid, bubble evolution, high-speed visualization, microheater
The paper deals with the experimental study of the process of subcooled liquid boiling on a transparent microheater with pulsed heat release. Dependences of the maximum bubble diameter, rates of their growth and times of boiling incipience on the heat flux density and degree of liquid subcooling in the ranges of 11-32 MW/m2 and 50 - 75 K, respectively, were obtained. The nucleation temperature was calculated for the studied regimes using the COMSOL Multiphysics software.
A.P. Zavyalov1, D.V. Sergachev2, I.P. Gulyaev2, O.O. Shichalin1,3, E.K. Papynov1,3 1Far Eastern Federal University, Vladivostok, Russia 2Khristianovich Institute of Theoretical and Applied Mechanics SB RAS, Novosibirsk, Russia 3Institute of Chemistry FEB RAS, Vladivostok, Russia
Keywords: refractory ceramic, spark plasma reaction-based sintering, hafnium carbide, hafnium nitride, system hafnium carbide-hafnium nitride
The paper presents a study in stability of ceramics of hafnium carbide-nitride subjected to impact of a nitrogen plasma jet in air atmosphere. The best thermal resistance was demonstrated for ceramics with N/C » 0.698, which is determined by the maximum of surface temperature and minimum mass loss in the series of HfC- HfN solid solutions.
