2304-9782, 2618-8686, 2405-7223
St. Petersburg Polytechnic University Journal. Physics and Mathematics
12
1
2019
1-170
RAR
RUS
11-27
Rodnyi
Petr
piotr_rodnyi@mail.ru
Garibin
Evgeniy A.
CJS "INCROM"
e.garibin@incrom.ru
St. Petersburg, Russian Federation
Venevtsev
Ivan D.
Peter the Great St. Petersburg Polytechnic University
Venevtsev.Ivan@gmail.com
St. Petersburg, Russian Federation
Davydov
Yuriy I.
Joint Institute for Nuclear Research
Davydov@jinr.ru
Dubna, Russian Federation
The application of barium fluoride luminescence: сhallenges and prospects
The problem of obtaining BaF2 crystals with a predominant sub-nanosecond luminescence component has been considered. A detailed analysis of methods for suppressing the slow component of the crystal luminescence was carried out. It was shown that the introduction of a number of dopants led to the suppression of the slow component, but, as a rule, the intensity of the sub-nanosecond component decreased, and the transparency and radiation hardness of the crystal also deteriorated. The results of spectral and kinetic measurements of BaF2:Tm and BaF2:Sc luminescence were presented. It was shown that the solution of the problem can be achieved by using an undoped BaF2 crystal in combination with a filter suppressing the slow luminescence component.
10.18721/JPM.12101
535.37
barium fluoride
core-valence luminescence
ultrafast scintillators
optical filters
https://physmath.spbstu.ru/article/2019.43.1/
1_11-27_12(1)2019.pdf
RAR
RUS
28-38
Politova
Galina
Baikov Institute of Metallurgy and Materials Science, RAS, Peter the Great St. Petersburg Polytechnic University
gpolitova@gmail.com
Moscow, Russian Federation, St. Petersburg, Russian Federation
Karpenkov
Aleksey
Tver State University
karpenkov_alex@mail.ru
Tver, Russian Federation
Kaminskaya
Tatiana
Lomonosov Moscow State University
ktp53@mail.ru
Moscow, Russian Federation
Ganin
Maksim
Baikov Institute of Metallurgy and Materials Science, RAS
ganmax_90@mail.ru
Moscow, Russian Federation
Kumar
Ravi
Indian Institute of Technology Madras
nvrk@iitm.ac.in
Chennai, India
Filimonov
Alexey
Peter the Great St. Petersburg Polytechnic University
filimonov@rphf.spbstu.ru
St. Petersburg, Russian Federation
High-magnetostriction Laves-phase alloy of the samarium-iron system: the structure and phase transformations
In this study, the SmFe2 alloy in a high-purity single-phase state has been prepared by the induction melting technique. The surface features of the alloy at room temperature were investigated using the atomic-force and magnetic-force microscopy. The forming of heterogeneous granular structure was revealed, the main structural elements were determined. The presence of the complex domain structure was shown, its description was presented and the domain sizes were found. The results of X-ray structural studies over the temperature range from 100 to 300 K were presented. The experimental data on the temperature dependences of magnetostriction in magnetic fields up to 1.2 T were obtained and analyzed in the region of the spin-reorientational phase transition. The existence of the “angular” phase was indirectly confirmed, its temperature boundaries were refined.
10.18721/JPM.12102
537.622: 539.378:620.186
rare-earth Laves phase
phase transition
magnetostriction
atomic force microscopy
structure
https://physmath.spbstu.ru/article/2019.43.2/
2_28-38_12(1)2019.pdf
RAR
RUS
39-49
Zaytsev
Dmitry
Peter the Great St. Petersburg Polytechnic University
zaitsev-aero@yandex.ru
E-5484-2014
56020596900
Smirnov
Evgeny
Peter the Great St. Petersburg Polytechnic University
aero@phmf.spbstu.ru
Russia, 195251, St.Petersburg, Polytechnicheskaya, 29
Method of calculation of turbulent Prandtl number for the SST turbulence model
We present a new model for turbulent Prandtl number that provides an improvement of prediction capabilities of the SST turbulence model in application to wall heat transfer problems. The model was calibrated using Kader’s empirical correlation for near-wall temperature profile. To get an initial assessment of the model we performed computations of the fully developed flow in a round tube and a flat channel with Prandtl number varying from 0.004 to 95; the simulation results were validated against benchmark DNS data and empirical correlations for the Nusselt number. According to the tests, applying the new model resulted in considerable reduction of the Nusselt number prediction error (by factor two and more) in the whole range of Prandtl number considered; the most pronounced effect was observed at Prandtl number values below 0.1.
10.18721/JPM.12103
532.517.4:536.24
turbulent flow
wall heat transfer
numerical simulation
turbulent Prandtl number
https://physmath.spbstu.ru/article/2019.43.3/
3_39-49_12(1)2019.pdf
RAR
RUS
50-60
Anikonov
Dmitriy
Sobolev Institute of Mathematics
anik@math.nsc.ru
Konovalova
Dina
Sobolev Institute of Mathematics
dsk@math.nsc.ru
Semi-bounded string’s vibrations initiated by the boundary regime
Transverse vibrations of a semi-bounded string consisting of different materials are considered. The homogeneous wave equation with piecewise constant coefficients stand duty as a mathematical model. As a first step, we have investigated the solution of this equation with zero Cauchy data. The existence and uniqueness of the generalized solution of the problem were proved and the properties of the solution were analyzed. The specificity of the obtained conclusions was discussed, in particular, the zones of oscillations’ propagation and of their absence were demonstrated. The obtained results are of a constructive character and can serve as a basis for the creation of a numerical algorithm. The importance of such problems is caused by their use in the theory of sensing inhomogeneous media by physical signals.
10.18721/JPM.12104
517.946
differential equation
discontinuous coefficient
sounding of unknown media
wave
https://physmath.spbstu.ru/article/2019.43.4/
4_50-60_12(1)2019.pdf
RAR
RUS
61-72
Onegin
Mikhail
NRC «Kurchatov Institute» – PNPI
onegin_ms@pnpi.nrcki.ru
Gatchina of Leningrad region, Russian Federation
Lyamkin
Vitaliy
NRC «Kurchatov Institute» – PNPI
lyamkin_va@pnpi.nrcki.ru
Gatchina of Leningrad region, Russian Federation
Serebrov
Anatolii
NRC «Kurchatov Institute» – PNPI
serebrov_ap@pnpi.nrcki.ru
Gatchina of Leningrad region, Russian Federation
The ultracold neutron supersource at the WWR-M reactor: a biological shielding design
In the paper, the biological shielding at the output of the ultracold neutron (UCN) supersource for the WWR-M reactor based on superfluid helium has been designed. The configuration of a casemate, i.e., a biological protection around the thermal column splitter, was calculated. The flux density, the spectrum and the angular divergence of the neutron beam at the exit of the intercanal part of the UCN source, as well as the materials’ geometry and composition inside the casemate were taken into account. The total thickness of the shielding made from steel, polyethylene and lead varied from 85 to 92 cm. The calculated maximum dose rate for neutrons and gammas on the casemate surface did not exceed 1 mrem p.h. Thus, the casemate design of the UCN supersource ensures the safe operation of the facility. The calculation was carried out by the Monte Carlo method within the SCALE-6.2 complex using the MAVRIC program.
10.18721/JPM.12105
621.039.539.7
WWR-M reactor
ultracold neutron source
biological shielding
nuclear safety
https://physmath.spbstu.ru/article/2019.43.5/
5_61-72_12(1)2019.pdf
RAR
RUS
73-86
Serebrov
Anatolii
NRC «Kurchatov Institute» – PNPI
serebrov_ap@pnpi.nrcki.ru
Gatchina of Leningrad region, Russian Federation
Lyamkin
Vitaliy
NRC «Kurchatov Institute» – PNPI
lyamkin_va@pnpi.nrcki.ru
Gatchina of Leningrad region, Russian Federation
Koptyuhov
Artem
NRC «Kurchatov Institute» – PNPI
t44h@yandex.ru
Gatchina of Leningrad region, Russian Federation
Onegin
Mikhail
NRC «Kurchatov Institute» – PNPI
onegin_ms@pnpi.nrcki.ru
Gatchina of Leningrad region, Russian Federation
Prudnikov
Dmitriy
NRC «Kurchatov Institute» – PNPI
dpvbox@mail.ru
Gatchina of Leningrad region, Russian Federation
Samodurov
Oleg
NRC «Kurchatov Institute» – PNPI
samodurov.o@yandex.ru
Gatchina of Leningrad region, Russian Federation
The low-temperature sub-system of the ultracold neutron supersource at the WWR-M reactor: A heat-hydraulic design study
Heat-hydraulic design studies of the low-temperature sub-system of the ultracold neutron (UCN) supersource at the WWR-M reactor have been presented in the paper. The studies were directed toward selection of the optimal working modes of the aggregate technological complex of this source. According to the calculation data, the Linde TCF-50 standard refrigerator was able to maintain the operating temperature of the thermal screens and the condensation of 50 liters of the deuterium pre-moderator in the chamber. Calculation results for the temperature field of the thermal shield placed in the low-temperature sub-system were used to select the location of the support structures for a superfluid helium vessel. Based on these calculations, an estimate of the total heat penetration at the UCN source chamber was made; it was equal to 35W. The capacity of the vacuum system for pumping the helium vapor and helium liquefier was established to be sufficient to maintain 35 liters of the superfluid UCN converter.
10.18721/JPM.12106
536.24
ultracold neutron source
superfluid helium
WWR-M reactor
https://physmath.spbstu.ru/article/2019.43.6/
6-73-86_12(1)2019.pdf
RAR
RUS
87-95
Savin
Vladislav
Ryazan State University named for S.A. Esenin
savin-vladislav@mail.ru
Ryazan, Russian Federation
Stepanov
Vladimir
Ryazan State University named for S.A.Yesenin
vl.stepanov@365.rsu.edu.ru
Shadrin
Maxim
Ryazan State University named for S.A.Yesenin
m.shadrin@russia.ru
Human visual model-based technology: measuring the geometric parameters of microinstrument
In the paper, a scheme of an optical microscope which includes a special bitelecentric optical system for the formation of a diode support and a telecentric objective for capturing the image has been designed and implemented. The use of such system makes it possible to reduce the diffraction effects at the edges of the shadow structure and to measure (using the microscope) the main parameters of a cutting microinstrument: its protrusion and diameter. An algorithm for modeling the two main visual channels of the human eye was developed. It allowed rapid detection of spatial-temporal processes and noise, and provided measuring the cutting edge contour of the instrument with a subpixel error (up to 0.01 pixel) and determining the dimensions of the cutting tool with an error of 0.5 μm.
10.18721/JPM.12107
621.391:681.142
telecentric objective
human visual model
microinstrument
subpixel accuracy
https://physmath.spbstu.ru/article/2019.43.7/
7_87-95_12(1)2019.pdf
RAR
RUS
96-104
0000-0003-3514-8577
Solovyev
Konstantin
Peter the Great St. Petersburg Polytechnic University
k-solovyev@mail.ru
Russia, 195251, St.Petersburg, Polytechnicheskaya, 29
Vinogradova
Maria
Peter the Great St. Petersburg Polytechnic University
vinogradova_39@mail.ru
St. Petersburg, Russian Federation
Two-electrode design for electrostatic ion trap integrable in polar coordinates
An electrostatic field with a square additive dependence on one of coordinates, also providing integrability of charged particle motion equations has been studied in the paper. The conditions of ion-motion finiteness were found for this field and in doing so it was shown the ion trap constructability. Potential parameter values providing a presence of sufficient workspace between two field-defining electrodes were revealed. An algorithm of optimal matching in beam characteristics and electrodes’ configuration was synthesized. To test the operability of the designed algorithm, three-dimensional equipotentials and a trajectory inside the ion-trap workspace were constructed. The ion trap designed in our studies can be put to experimental use as a mass spectrometer, extending the class of electrostatic ion traps presented by well-known Orbitrap and Cassini trap.
10.18721/JPM.12108
537.534.3:621.384.8 (075.8)
mass spectrometry
ion trap
ideal focusing
https://physmath.spbstu.ru/article/2019.43.8/
8_96-104_12(1)2019.pdf
RAR
RUS
105-116
Kapustin
Valentin
Peter the Great St. Petersburg Polytechnic University
Valentin.Kapustin.2014@yandex.ru
St. Petersburg, Russian Federation
Pashkevich
Dmitrii
Peter the Great St. Petersburg Polytechnic University
pashkevich-ds@yandex.ru
St. Petersburg, Russian Federation
Mukhortov
Dmitrii
FSUE RSC "Applied Chemistry"
St. Petersburg, Russian Federation
Petrov
Valentin
FSUE RSC "Applied Chemistry"
valentinpetrov46@mail.ru
St. Petersburg, Russian Federation
Alexeev
Yury
«New Chemical Products» Ltd.
alexeev-588@yandex.ru
St. Petersburg, Russian Federation
The water vapor conversion during the interaction between an evaporated hydrogen fluoride solution and carbon in the filtration combustion mode
The results of laboratory studies of the water vapor conversion when an evaporized aqueous solution (EAS) of HF and oxygen is being fed into a stationary layer of granular graphite have been presented. It was established that the characteristic time for the water vapor conversion upon the contact of the EAS of HF with carbon at a temperature of about 1500 K was 10 s. Comparison of the experimental results with the literature data on high-temperature interaction of water vapor and carbon showed that HF had little or no effect on the rate of this interaction at a temperature of about 1500 K. Our method derived from the high-temperature interaction of the EAS of HF with carbon can serve as the basis of an industrial technology for the dehydration of an aqueous solution of HF, including azeotropic one.
10.18721/JPM.12109
662.612.3:661.487.1
hydrogen fluoride
hydrofluoric acid
water gas
filtration combustion
https://physmath.spbstu.ru/article/2019.43.9/
9_105-116_12(1)2019.pdf
RAR
RUS
117-127
Chupin
Vladimir
chupin@poi.dvo.ru
Dolgikh
Grigoriy
dolgikh@poi.dvo.ru
Gusev
Egor
V.I. Il'ichev Pacific Oceanological Institute
gusev.e.s.95@gmail.com
Vladivostok, Russian Federation
Recording typhoons’ infrasonic disturbances by laser strainmeters
In the paper, the field studies of powerful infrasonic disturbances in the range of "voice of the sea" (7 – 9 Hz) caused by tropical cyclones (typhoons) in the southeastern region of the Far Eastern Federal District (Russia) and the water area of the Sea of Japan have been presented. Event monitoring was carried out using the laser-interference measuring complex located permanently in the South of Primorski Krai. The dynamic spectrograms of the observable events were analyzed and their connection with various meteorological phenomena, such as wind and sea waves, was followed. Using the satellite data, a connection between the distribution of the area of typhoons influence in the region and the observed infrasound excitation was found. The conclusions were drawn regarding the correlation between the exhibition of the "voice of the sea" microseisms and the initiation of primary and secondary microseisms, as well as the one between the "voice of the sea" microseisms’ disappearance and the corresponding end of primary microseisms. No dependence of the signal level on the wind speed in the area of the measuring range location was established.
10.18721/JPM.12110
534.2
infrasonic wave
laser strainmeter
typhoon
voise of sea
https://physmath.spbstu.ru/article/2019.43.10/
10_117-127_12(1)2019.pdf
RAR
RUS
128-141
Kiselev
Kirill
Peter the Great St. Petersburg Polytechnic University
kvladimirovich10@gmail.com
St. Petersburg, Russian Federation
Frolov
Maxim
Peter the Great St. Petersburg Polytechnic University
frolov_me@spbstu.ru
St. Petersburg, Russian Federation
Chistiakova
Olga
Peter the Great St. Petersburg Polytechnic University
Chistiakova.Olga@gmail.com
St. Petersburg, Russian Federation
A posteriori error estimate for Reissner – Mindlin plates: verification of implementations and numerical testing
A posteriori error estimate for accuracy control of approximate solutions for the problem of Reissner – Mindlin plates bending has been analyzed in the paper. The estimate was constructed using the functional approach based on rigorous mathematical grounds, in particular, on methods of functional analysis. It is valid for all conforming approximations of exact solutions, and therefore, it is robust. The estimate is guaranteed in practical implementations due to reliability of the respective inequality. The above-mentioned properties of the method of error control are very desirable for engineering analysis, where some details of computations might be hidden. Our paper investigated two independent implementations of the estimate. Using specially constructed numerical tests, correctness of both implementation algorithms and similarity of the obtained results for all examples were shown. An overestimation of the true error was established to remain acceptable for a wide range of plate thickness values.
10.18721/JPM.12111
519.63
a posteriori error estimate
finite element method
Reissner – Mindlin plate
https://physmath.spbstu.ru/article/2019.43.11/
11_128-141_12(1)2019.pdf
RAR
RUS
142-155
Fedotov
Aleksandr
Institute for Problems of Mechanical Engineering, RAS
alvafed@yandex.ru
St. Petersburg, Russian Federation
The damping of the distributed system vibrations using piezoelectric transducers: simulation
The present paper continues the author’s studies where the problem of the control of forced bending vibrations of a metal beam using piezoelectric sensors and actuators has been investigated. In those studies, all the control results were obtained experimentally. However, in order to make the design of the control systems the most effective, it was necessary to develop a numerical model, which would allow one to get the results for different variants of such systems, and that was the objective of the present study. In this study, the main experimental data were reproduced numerically on a basis of the finite element model of the object. In addition, new modal control systems were designed, providing a more efficient reduction of the amplitude of resonance vibrations of a beam compared to the systems considered experimentally.
10.18721/JPM.12112
531.391+681.5.01
active vibration control
mechatronics
modal control
piezoelectric transducer
finite element model
https://physmath.spbstu.ru/article/2019.43.12/
12_142-155_12(1)2019.pdf
RAR
RUS
156-166
Polyanskiy
Sergey
Institute for Problems in Mechanical Engineering of the RAS
svpolyanskiy@gmail.com
St. Petersburg, Russian Federation
Belyaev
Alexander
Institute for Problems of Mechanical Engineering of RAS
13augen@mail.ru
A quasistatic approach to the thermoelasticity problem of rotating bodies
The non-stationary problem of thermoelasticity for rotating bodies has been solved through determining the optimal temperature and stress fields in the rolling mills of hot rolling systems, this determination being an issue of the day. The Eulerian approach was applied, it allowed us to reduce the number of independent variables and consider these fields as quasistatic ones. The heavy temperature gradients and stresses bound up with them, as well as the rotating nature of these fields are typical for the processes taking place in the roll core. To solve the problem of simulation of these processes, we proposed to use Fourier series, which allowed us to obtain a solution with a sufficient accuracy for the large number of terms of the series being considered. The peculiarity of the solution obtained is that the stress maximum locates at an insignificant depth beneath the roll surface.
10.18721/JPM.12113
539.3
temperature stress
mill roll
rotating system
Fourier series
https://physmath.spbstu.ru/article/2019.43.13/
13_156-166_12(1)2019.pdf