Pub Date : 2022-09-01DOI: 10.33257/phchgd.21.1.893
V. N. Emel’yanov, I. Teterina, K. Volkov
Development of tools for modeling the motion of agglomerated particles with a complex composition and shape in a flow of combustion products is of interest for problems related to the description of the motion of the condensed phase in the internal channels of solid rocket motors. An approach is developed to simulate unsteady processes that occur when a viscous incompressible fluid flows around a particle consisting of an aluminum droplet and a condensed oxide particle attached to it. Methods for taking into account the sliding of the attached oxide particle over the surface of the aluminum droplet are proposed. The computational results are used to find the drag and heat transfer coefficients of a non-spherical particle at flow velocities corresponding to the formation of separation zones. The developed model is one of the components of a more general mathematical model designed for calculating two-phase flows of combustion products and created with a multi-scale approach to simulation of two-phase flows.
{"title":"Drag and heat transfer of metal and oxide agglomerates in flow of combustion products of solid propellant","authors":"V. N. Emel’yanov, I. Teterina, K. Volkov","doi":"10.33257/phchgd.21.1.893","DOIUrl":"https://doi.org/10.33257/phchgd.21.1.893","url":null,"abstract":"Development of tools for modeling the motion of agglomerated particles with a complex composition and shape in a flow of combustion products is of interest for problems related to the description of the motion of the condensed phase in the internal channels of solid rocket motors. An approach is developed to simulate unsteady processes that occur when a viscous incompressible fluid flows around a particle consisting of an aluminum droplet and a condensed oxide particle attached to it. Methods for taking into account the sliding of the attached oxide particle over the surface of the aluminum droplet are proposed. The computational results are used to find the drag and heat transfer coefficients of a non-spherical particle at flow velocities corresponding to the formation of separation zones. The developed model is one of the components of a more general mathematical model designed for calculating two-phase flows of combustion products and created with a multi-scale approach to simulation of two-phase flows.","PeriodicalId":309290,"journal":{"name":"Physical-Chemical Kinetics in Gas Dynamics","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123686314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-11-25DOI: 10.33257/phchgd.20.2.832
A. Reshmin, V. Trifonov, V. G. Lushchik, M. S. Makarova
Using the differential turbulence model, a numerical study of the possibility of relaminarization of the flow in a pipe is carried out for three variants of input devices with different velocity profiles and small-scale turbulence. The most promising is the experimentally investigated option with the organization of a two-zone flow with a slowed flow in the central region of the pipe and accelerated flow in the wall region. In this variant, the Reynolds number of relaminarization Re* is 16000. It is shown that a further increase in the number of Re* can be obtained by decreasing the turbulence intensity and turbulence scale at the inlet.
{"title":"On the Possibility of Reducing Friction due to Relaminarization of the Flow in the Pipe","authors":"A. Reshmin, V. Trifonov, V. G. Lushchik, M. S. Makarova","doi":"10.33257/phchgd.20.2.832","DOIUrl":"https://doi.org/10.33257/phchgd.20.2.832","url":null,"abstract":"Using the differential turbulence model, a numerical study of the possibility of relaminarization of the flow in a pipe is carried out for three variants of input devices with different velocity profiles and small-scale turbulence. The most promising is the experimentally investigated option with the organization of a two-zone flow with a slowed flow in the central region of the pipe and accelerated flow in the wall region. In this variant, the Reynolds number of relaminarization Re* is 16000. It is shown that a further increase in the number of Re* can be obtained by decreasing the turbulence intensity and turbulence scale at the inlet.","PeriodicalId":309290,"journal":{"name":"Physical-Chemical Kinetics in Gas Dynamics","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129233443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-11-06DOI: 10.33257/phchgd.20.2.822
I. Brykina, M. Bragin, L. Egorova
Different approaches are developed to modelling the destruction of cosmic bodies in the atmosphere into a large number of fragments. It is assumed that they first move with a common shock wave as a single body deformed by pressure forces. Four models of meteoroid disruption into a cloud of fragments are considered: two developed by the authors, and two generally accepted. The main differences between the models are showed. Using these models, numerical solutions of the meteor physics equations taking into account ablation are obtained to simulate the interaction of the Chelyabinsk meteoroid with the atmosphere. Solutions for different models are compared with each other and with observational data. After meteoroid’s fragments diverge over a long distance, their independent movement is considered. Formulas for the probability and cumulative distribution of fragments by mass are obtained using the results of experiments on the destruction of bodies under high-speed impact. The cumulative distribution is compared with the experimental data and also with the mass distributions of the recovered meteorites in the cases of a significant number of fragments found. The mass and luminosity of the disrupted meteoroid are determined by integration over all fragments using the probabilistic mass distribution as the initial one. The mass and velocity of each fragment are determined from the meteor physics equations.
{"title":"On Models of Meteoroids Fragmentation in the Atmosphere","authors":"I. Brykina, M. Bragin, L. Egorova","doi":"10.33257/phchgd.20.2.822","DOIUrl":"https://doi.org/10.33257/phchgd.20.2.822","url":null,"abstract":"Different approaches are developed to modelling the destruction of cosmic bodies in the atmosphere into a large number of fragments. It is assumed that they first move with a common shock wave as a single body deformed by pressure forces. Four models of meteoroid disruption into a cloud of fragments are considered: two developed by the authors, and two generally accepted. The main differences between the models are showed. Using these models, numerical solutions of the meteor physics equations taking into account ablation are obtained to simulate the interaction of the Chelyabinsk meteoroid with the atmosphere. Solutions for different models are compared with each other and with observational data. After meteoroid’s fragments diverge over a long distance, their independent movement is considered. Formulas for the probability and cumulative distribution of fragments by mass are obtained using the results of experiments on the destruction of bodies under high-speed impact. The cumulative distribution is compared with the experimental data and also with the mass distributions of the recovered meteorites in the cases of a significant number of fragments found. The mass and luminosity of the disrupted meteoroid are determined by integration over all fragments using the probabilistic mass distribution as the initial one. The mass and velocity of each fragment are determined from the meteor physics equations.","PeriodicalId":309290,"journal":{"name":"Physical-Chemical Kinetics in Gas Dynamics","volume":"120 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128108728","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-11-06DOI: 10.33257/phchgd.20.2.828
S. Maslov, V. Natyaganov
Basing on electrohydrodynamics equations system, the article researches the role of electromagnetic factors with trigger nature in generating tornadoes: atmospheric electric field perturbations under thundercloud and giant dielectric permittivity effect of cloud as water droplets suspension with thin surface double electric layer. The work considers the influence of tripole cloud charge structure and effect of giant electric permittivity on forming tornado funnels and appearing num-ber of accompanying specific phenomena: a “collar” in the funnel base, “devil horns” and growth of dust or water hill (cascade) toward the descending tornado funnel. Other factors (same or different direction of thundercloud rotation, distinguish of oxygen and nitrogen magnetic properties etc.) usually play secondary role in tornado-like vortices formation.
{"title":"Role of giant dielectric permittivity effect during tornado generation process","authors":"S. Maslov, V. Natyaganov","doi":"10.33257/phchgd.20.2.828","DOIUrl":"https://doi.org/10.33257/phchgd.20.2.828","url":null,"abstract":"Basing on electrohydrodynamics equations system, the article researches the role of electromagnetic factors with trigger nature in generating tornadoes: atmospheric electric field perturbations under thundercloud and giant dielectric permittivity effect of cloud as water droplets suspension with thin surface double electric layer. The work considers the influence of tripole cloud charge structure and effect of giant electric permittivity on forming tornado funnels and appearing num-ber of accompanying specific phenomena: a “collar” in the funnel base, “devil horns” and growth of dust or water hill (cascade) toward the descending tornado funnel. Other factors (same or different direction of thundercloud rotation, distinguish of oxygen and nitrogen magnetic properties etc.) usually play secondary role in tornado-like vortices formation.","PeriodicalId":309290,"journal":{"name":"Physical-Chemical Kinetics in Gas Dynamics","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122151763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-11-06DOI: 10.33257/phchgd.20.2.838
Y. Golubev, E. Melkumova
We consider the problem of brittle cylinder grasping by the manipulator fingers. Each finger contacts the cylinder in a single supporting point. Using numerical simulations and analytically, possible locations of the contact points on the cylinder, for which there is a kinetostatics problem solution when the cylinder is moved by three fingers, are received. There is an analogy of the equilibrium of a three-legged robot on a cylinder for the problem of transfer by a manipulator with a three-finger grasp of a cylinder.
{"title":"Brittle Cylinder Transfering by a Manipulator with Three Fingers","authors":"Y. Golubev, E. Melkumova","doi":"10.33257/phchgd.20.2.838","DOIUrl":"https://doi.org/10.33257/phchgd.20.2.838","url":null,"abstract":"We consider the problem of brittle cylinder grasping by the manipulator fingers. Each finger contacts the cylinder in a single supporting point. Using numerical simulations and analytically, possible locations of the contact points on the cylinder, for which there is a kinetostatics problem solution when the cylinder is moved by three fingers, are received. There is an analogy of the equilibrium of a three-legged robot on a cylinder for the problem of transfer by a manipulator with a three-finger grasp of a cylinder.","PeriodicalId":309290,"journal":{"name":"Physical-Chemical Kinetics in Gas Dynamics","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124877370","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-11-06DOI: 10.33257/phchgd.20.2.826
B. Kert, V. A. Chubasov, E. Znamensky, V. Kravtsov, Y. O. Pavlov, A. .. Panchenko, Yu. V. Genkin, Voenmeh
Based on the analysis of existing technical solutions, promising structural designs of ammunition with rocket ramjet of 130, 152, and 203 mm caliber have been developed. Mathematical models of the ballistic functioning of artillery projectiles are implemented in software, which allow us to analyze the influence of design parameters on the ballistic functioning of active, active-reactive ammunition and ammunition with rocket ramjet. For ammunition of a promising scheme, a calculation was made of the support parameters and characteristic periods of the rocket ramjet, providing the possibility of increasing the firing range to 60 km or more. The carried out studies allow us to conclude that it is possible and advisable to develop long range projectiles equipped with an out-barrel dispersal system including rocket ramjet on paste fuel with or without solid propellant ramjet.
{"title":"Ballistic opportunities' evaluation of artillery projectile with a rocket ramjet","authors":"B. Kert, V. A. Chubasov, E. Znamensky, V. Kravtsov, Y. O. Pavlov, A. .. Panchenko, Yu. V. Genkin, Voenmeh","doi":"10.33257/phchgd.20.2.826","DOIUrl":"https://doi.org/10.33257/phchgd.20.2.826","url":null,"abstract":"Based on the analysis of existing technical solutions, promising structural designs of ammunition with rocket ramjet of 130, 152, and 203 mm caliber have been developed. Mathematical models of the ballistic functioning of artillery projectiles are implemented in software, which allow us to analyze the influence of design parameters on the ballistic functioning of active, active-reactive ammunition and ammunition with rocket ramjet. For ammunition of a promising scheme, a calculation was made of the support parameters and characteristic periods of the rocket ramjet, providing the possibility of increasing the firing range to 60 km or more. The carried out studies allow us to conclude that it is possible and advisable to develop long range projectiles equipped with an out-barrel dispersal system including rocket ramjet on paste fuel with or without solid propellant ramjet.","PeriodicalId":309290,"journal":{"name":"Physical-Chemical Kinetics in Gas Dynamics","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116760124","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-11-06DOI: 10.33257/phchgd.20.2.819
V. Sakharov, I. Senyuev, B. Zhestkov
Using the calculation and experimental methods, the catalytic activity of samples from super high-temperature ceramics based on hafnium diboride was determined at TsAGI VAT-104 hypersonic wind tunnel equipped with a high-frequency induction gas heater was used to study the overflow and heating of ceramic disks at surface temperatures up to 3500 K. A significant effect of the catalytic properties of materials at ultrahigh flow rates on the heat flow was demonstrated. At the same time, for the conditions of experiments at the VAT-104 facility, in the framework of the Navier ‒ Stokes equations, a numerical simulation of the flow of chemically nonequilibrium air plasma over these models was carried out. By comparing of the calculated and experimental values of the heat fluxes to the surface of the disk, the catalytic activity of the ceramic material is determined.
{"title":"Numerical and experimental study of catalytic activity of super high-temperature ceramics","authors":"V. Sakharov, I. Senyuev, B. Zhestkov","doi":"10.33257/phchgd.20.2.819","DOIUrl":"https://doi.org/10.33257/phchgd.20.2.819","url":null,"abstract":"Using the calculation and experimental methods, the catalytic activity of samples from super high-temperature ceramics based on hafnium diboride was determined at TsAGI VAT-104 hypersonic wind tunnel equipped with a high-frequency induction gas heater was used to study the overflow and heating of ceramic disks at surface temperatures up to 3500 K. A significant effect of the catalytic properties of materials at ultrahigh flow rates on the heat flow was demonstrated. At the same time, for the conditions of experiments at the VAT-104 facility, in the framework of the Navier ‒ Stokes equations, a numerical simulation of the flow of chemically nonequilibrium air plasma over these models was carried out. By comparing of the calculated and experimental values of the heat fluxes to the surface of the disk, the catalytic activity of the ceramic material is determined.","PeriodicalId":309290,"journal":{"name":"Physical-Chemical Kinetics in Gas Dynamics","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125338512","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-11-06DOI: 10.33257/phchgd.20.2.791
E. Volkov, A. Fedyushkin
{"title":"Symmetry of the flow of Newtonian and non-Newtonian fluid in a flat diffuser and confusor","authors":"E. Volkov, A. Fedyushkin","doi":"10.33257/phchgd.20.2.791","DOIUrl":"https://doi.org/10.33257/phchgd.20.2.791","url":null,"abstract":"","PeriodicalId":309290,"journal":{"name":"Physical-Chemical Kinetics in Gas Dynamics","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128476532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-04-05DOI: 10.33257/PHCHGD.20.1.799
N. Bystrov, A. Emelianov, A. Eremin, P. Yatsenko
This paper presents new data on the time profiles of the concentration of atomic oxygen obtained during high-temperature oxidation of n-butanol behind reflected shock waves in the temperature range of 1600–2600 K at pressures of 2–3 bar. The kinetics of the reaction of nC4H9OH with atomic oxygen has been studied. As a source of oxygen atoms, a small amount of nitrous oxide N2O was added to the mixture. Quantitative measurements of the concentration profiles of oxygen atoms were carried out using atomic resonance absorption spectroscopy (ARAS) on the resonance line of the O atom (λ = 130.5 nm). Kinetic analysis of the obtained data was carried out using the Chemkin package. The experimental results obtained are compared with actual kinetic combustion schemes of n-butanol. It is shown that the kinetic schemes of n-butanol combustion available in the literature in some cases do not exactly agree with the experimental results. An analysis of possible additions to the existing kinetic schemes was carried out. As a result, it was suggested possible improvement to the existing kinetic schemes for the combustion of n-butanol at high temperatures.
{"title":"Experimental study of reaction of n-butanol with oxygen behind shock waves using ARAS method","authors":"N. Bystrov, A. Emelianov, A. Eremin, P. Yatsenko","doi":"10.33257/PHCHGD.20.1.799","DOIUrl":"https://doi.org/10.33257/PHCHGD.20.1.799","url":null,"abstract":"This paper presents new data on the time profiles of the concentration of atomic oxygen obtained during high-temperature oxidation of n-butanol behind reflected shock waves in the temperature range of 1600–2600 K at pressures of 2–3 bar. The kinetics of the reaction of nC4H9OH with atomic oxygen has been studied. As a source of oxygen atoms, a small amount of nitrous oxide N2O was added to the mixture. Quantitative measurements of the concentration profiles of oxygen atoms were carried out using atomic resonance absorption spectroscopy (ARAS) on the resonance line of the O atom (λ = 130.5 nm). Kinetic analysis of the obtained data was carried out using the Chemkin package. The experimental results obtained are compared with actual kinetic combustion schemes of n-butanol. It is shown that the kinetic schemes of n-butanol combustion available in the literature in some cases do not exactly agree with the experimental results. An analysis of possible additions to the existing kinetic schemes was carried out. As a result, it was suggested possible improvement to the existing kinetic schemes for the combustion of n-butanol at high temperatures.","PeriodicalId":309290,"journal":{"name":"Physical-Chemical Kinetics in Gas Dynamics","volume":"273 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124548128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-04-05DOI: 10.33257/phchgd.20.1.764
Vladimir A Frost
The results of a numerical calculating of the propagation of plane wave of reaction described by the equations of one-dimensional unsteady heat conduction and diffusion are presented. To describe the rates of energy supply and the change in mixture composition, macrokinetic equations are used. The set of dimensionless variables used is such that, in the simplest case (when thermal parameters and density are constant), only the igniter temperature, the initial temperature of the mixture and the ratio of activation energy to calorific value of a fuel, have a decisive influence on the propagation process. The reaction rate constant enters only in the recount of results into physical variables and does not affect the stability limits. In the range of Lewis numbers from 0 to 1, stationary, oscillatory, and pulsating modes of reaction wave propagation are obtained. The boundaries that determine the types of the propagating thermal waves are constructed.
{"title":"The influence of the Lewis number on the propagation of a plane thermal wave","authors":"Vladimir A Frost","doi":"10.33257/phchgd.20.1.764","DOIUrl":"https://doi.org/10.33257/phchgd.20.1.764","url":null,"abstract":"The results of a numerical calculating of the propagation of plane wave of reaction described by the equations of one-dimensional unsteady heat conduction and diffusion are presented. To describe the rates of energy supply and the change in mixture composition, macrokinetic equations are used. The set of dimensionless variables used is such that, in the simplest case (when thermal parameters and density are constant), only the igniter temperature, the initial temperature of the mixture and the ratio of activation energy to calorific value of a fuel, have a decisive influence on the propagation process. The reaction rate constant enters only in the recount of results into physical variables and does not affect the stability limits. In the range of Lewis numbers from 0 to 1, stationary, oscillatory, and pulsating modes of reaction wave propagation are obtained. The boundaries that determine the types of the propagating thermal waves are constructed.","PeriodicalId":309290,"journal":{"name":"Physical-Chemical Kinetics in Gas Dynamics","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125247542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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