29TH RUSSIAN CONFERENCE ON MATHEMATICAL MODELLING IN NATURAL SCIENCES最新文献

{"title":"Mathematical models of active acoustic impact on diffusion in reservoirs with oil hierarchic inclusions","authors":"A. Khachay","doi":"10.1063/5.0060442","DOIUrl":"https://doi.org/10.1063/5.0060442","url":null,"abstract":"The work is devoted to the study of the influence of turbulent fluid movement in a vertical well passing through a reservoir with oil hierarchical inclusions. The processes of development of oil and gas fields are associated with the movement of multiphase multicomponent media, which are characterized by noneqiulibrium and nonlinear rheological properties. The actual behavior of reservoir systems is determined by complexity of moving fluids rheology and the morphological structure of the porous medium, as well as the variety of interaction processes between the fluid and the porous medium. Taking these factors into account it is necessary for a meaningful description of filtration processes due to nonlinearity, noneqiulibrium and heterogeneity inherent in real systems. At the same time, new synergetic effects are revealed (loss of stability with the onset of oscillations, the formation of ordered structures). This allows us to propose new methods for monitoring and managing complex natural systems that are tuned to account for these phenomena. In this case, the reservoir system from which it is necessary to extract oil is a complex dynamic hierarchical system. An algorithm for mathematical modeling of the propagation of a longitudinal acoustic wave in a layered block medium with a plastic layer above a reservoir with different-scale oil hierarchical inclusions, taking into account the effect of fluid turbulence in the reservoir, has been developed. The iterative algorithm uses integro-differential equations, which was previously tested for solving direct problems of acoustic wave propagation in a layered-block medium with hierarchical inclusions. Turbulent motion in the well creates, due to a set of vortices of different scales, a set of additional frequencies to the main frequency of acoustic excitation of the reservoir medium, which sets in motion both large and smaller hierarchical inclusions. Energy transfer occurs from larger eddies to smaller ones, depending on the viscosity of the reservoir medium. This effect can be controlled to enhance oil recovery from the reservoir.","PeriodicalId":177478,"journal":{"name":"29TH RUSSIAN CONFERENCE ON MATHEMATICAL MODELLING IN NATURAL SCIENCES","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132957008","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}

{"title":"Finite element model of bending plate with considering shear deformations","authors":"Yu Ya Tyukalov","doi":"10.1063/5.0059516","DOIUrl":"https://doi.org/10.1063/5.0059516","url":null,"abstract":"The arbitrary quadrangular finite element of plate is proposed. Finite element is based on piecewise constant approximations of moments and shear forces. The values of moments and shear forces at the finite element mesh nodes are used as unknown parameters. To construct the solution, the minimum additional energy principle is used. Using the possible displacements principle, algebraic equilibrium equations are formed for the finite element mesh nodes. The vertical displacement and rotation angles along the coordinate axes are considered as possible. The resulting equilibrium equations are included in the additional energy functional using Lagrange multipliers. Lagrange multipliers are vertical displacements and rotation angles values of the finite element mesh nodes. The use of piecewise constant approximations of moments and shear forces allows one to obtain a block-diagonal structure of the flexibility matrix. The solution is reduced to linear algebraic equations system for Lagrange multipliers. The proposed finite element allows one to consider shear deformations regardless of the plate thickness ratio to its dimensions. There is no “locking” effect when thin plates are calculating. Comparison of the calculating oblique plate results with the results of calculations using other programs is performed. It is shown that when the finite element mesh is refined, the displacements values tend to exact values from above.","PeriodicalId":177478,"journal":{"name":"29TH RUSSIAN CONFERENCE ON MATHEMATICAL MODELLING IN NATURAL SCIENCES","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133298533","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}

{"title":"Modeling of elastoplastic deformation of low-carbon steel along multi-link plane strain trajectories","authors":"A. Alekseev, V. Zubchaninov, V. Gultiaev, E. Alekseeva","doi":"10.1063/5.0059630","DOIUrl":"https://doi.org/10.1063/5.0059630","url":null,"abstract":"To verify the mathematical model of the theory of processes, numerical calculations of the complex elastoplastic deformation of low-carbon steel 45 along multi-link strain trajectories with different corner angles under combined tension-compression with torsion were carried out. The numerical calculations are compared with the experimental data obtained by the authors on the SN-EVM testing machine on thin-walled tubular specimen. It is shown that the used mathematical model qualitatively and quantitatively satisfactorily describes the main effects of complex plastic deformation for the class of plane multi-link broken strain trajectories.","PeriodicalId":177478,"journal":{"name":"29TH RUSSIAN CONFERENCE ON MATHEMATICAL MODELLING IN NATURAL SCIENCES","volume":"160 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123026344","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}

{"title":"Residual stresses in plate material due to a moving heat source","authors":"A. Tkacheva, E. Abashkin","doi":"10.1063/5.0059503","DOIUrl":"https://doi.org/10.1063/5.0059503","url":null,"abstract":"The paper presents a study of temperature stresses in a plate from steel 0818X10HT with a heat source passing its surface in a straight line with a certain speed. A mathematical model is made based on the Prandtl-Reuss model where Hooke’s law is replaced with Duhamel-Neumann’s law. Von Mises condition is taken as plastic flow condition where creep limit parabolically depends on temperature. Residual stress fields are considered, based on the heat source speed. Residual stress values obtained as the result of calculations are compared to the experimental stresses obtained from the plate, using residual stress analyzer RIGAKU MSF-3M.","PeriodicalId":177478,"journal":{"name":"29TH RUSSIAN CONFERENCE ON MATHEMATICAL MODELLING IN NATURAL SCIENCES","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128583723","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}

{"title":"Mathematical model of antitumor immune response of organism regulation","authors":"V. Chigvintsev, P. Trusov, N. Zaitseva","doi":"10.1063/5.0059532","DOIUrl":"https://doi.org/10.1063/5.0059532","url":null,"abstract":"A predictive mathematical model capable to describe a complex multicomponent process of interaction of the immune system elements under occurring of the abnormal tissue cells that is reasoned by its synthetic function violation is demonstrated by this work. The model has been developed within the concept of the multi-level model of the human organism and is targeted to describe the different-scale processes occurring during the development of cancer. The structural chart of the model includes the following elements: tissue cells, characterized by a set of parameters, and a set of interrelated components of the immune system, which are the most important components in the body's response to the formation of cancer cells. Modelling takes into account the functional state of the studied organs. As the factors, having impact on the state changes, natural aging and the negative effects of diverse chemicals entering from the environment can be distinguished. Building on the created interaction scheme, the ordinary differential equations are written, which are described by the First Order ODE’s with lags of the argument. A number of computational experiments on tumor growth have been performed. The obtained calculated data on the dynamics of changes in the characteristics of the cell populations of the tissue under consideration in individual points and in the entire volume as a whole have been analyzed.","PeriodicalId":177478,"journal":{"name":"29TH RUSSIAN CONFERENCE ON MATHEMATICAL MODELLING IN NATURAL SCIENCES","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115499246","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}

{"title":"Stress-deformable state research and strength estimation of a composite smart rotor blade with variable geometry","authors":"P. Pisarev, A. Anoshkin, E. Barkanov, E. G. Kungurtseva","doi":"10.1063/5.0059533","DOIUrl":"https://doi.org/10.1063/5.0059533","url":null,"abstract":"In this work, the research results are presented highlighting the influence of the spar structure on a helicopter SMART rotor blade stress-strain state, taking into account the operational and control loads, geometry features, reinforcement scheme and the composite material structure. To describe the mechanical behavior of a model SMART blade, it was proposed to use a coupled piezoelectroelastic setting that takes into account the forward and reverse piezoelectric effect occurring in piezoelectric actuators. Evaluation of a SMART controlled blade strength with a C- and D-shaped spars was carried out.","PeriodicalId":177478,"journal":{"name":"29TH RUSSIAN CONFERENCE ON MATHEMATICAL MODELLING IN NATURAL SCIENCES","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114401393","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}

{"title":"The analysis of mechanisms of inelastic strain of composites in the concentrator areas with respect to structural parameters","authors":"E. Strungar, D. Lobanov, V. Wildemann","doi":"10.1063/5.0060203","DOIUrl":"https://doi.org/10.1063/5.0060203","url":null,"abstract":"The paper provides experimental studies of mechanical behavior of composites in concentrators areas with respect to structural parameters. The authors obtained the results of assessment of the effect of stress concentrator size with respect to the parameters of fiber-laminated composite material structure in the study of processes of inelastic strain and destruction. The authors obtained experimental data about the impact of large-scale effect on the processes of initiation and development of defects in the stress concentrators areas in structurally non-homogeneous material under quasi-static loading. The authors have analyzed the evolution of non-homogeneous strain fields on the surface of composite samples of the studied structure.","PeriodicalId":177478,"journal":{"name":"29TH RUSSIAN CONFERENCE ON MATHEMATICAL MODELLING IN NATURAL SCIENCES","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124743364","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}

{"title":"Effective elastic moduli of a plain wave ceramic textile composite with local processing defects in the flexible graphite matrix","authors":"D. Dedkov, A. Zaitsev, Vitaliy Koksharov, A. Tashkinov","doi":"10.1063/5.0059559","DOIUrl":"https://doi.org/10.1063/5.0059559","url":null,"abstract":"Effective elastic moduli of a plain woven textile composite with a flexible graphite based matrix (made by rolling of foil layers) and ceramic fibers were predicted. We examined the layer of a textile composite of 2,5D thickness with the reinforcement plain woven fabric formed by ceramic fibers round in their cross-sections with diameter D . The warp and weft cloth fiber curvature was set by the segment of a circle with the central angle α = π/4 and a straight line section. Due to a small amount of strain angles, α were assumed as invariable under layer loading. We investigated the most typical local technological defects, i.e. caverns that are formed as a result of a random warp or weft breakage and occur by the prick stitch of textile layers, but can also be contained in the source textile before the prick. The dimensions of examined defects were commensurable with the characteristic scale of heterogeneity; they did not considerably change integral reinforcement coefficients of the composite or were partly or completely filled by the matrix material. The influence of the length scale and presence of local technological defects on the values of the effective Young moduli and Poisson ration were determined. The obtained results demonstrate that the concentration (i.e. the number of breakages and pinched fibers) of the separate local technological defects located at least at the distance of two or three length scales of meshes (caused by the fiber weaves of a reinforcement plain woven fabric) in a structure element made of a textile composite is not a crucial factor that significantly influences the values of elastic moduli. However the local defect concentration predetermines the scenario of the damage evolution.","PeriodicalId":177478,"journal":{"name":"29TH RUSSIAN CONFERENCE ON MATHEMATICAL MODELLING IN NATURAL SCIENCES","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124474127","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}

{"title":"Influence of gradient distribution of boron carbide particles in aluminum bronze-based composite on its mechanical properties","authors":"A. Smolin, G. Eremina","doi":"10.1063/5.0059575","DOIUrl":"https://doi.org/10.1063/5.0059575","url":null,"abstract":"To enhance the functional properties of aluminum bronze, different reinforcing inclusions may be used to produce metal matrix composite. In this study, we proposed a numerical model to investigate the influence of different spatial distributions of boron carbide particles in the bronze matrix on such mechanical properties as tensile strength and hardness. The model is based on the method of movable cellular automata, which is a representative of computational particle mechanics and allows considering the composite structure explicitly. The simulation results show that introducing boron carbide inclusions into aluminum bronze matrix leads to enhancing the hardness and tensile strength but reducing the ultimate strain in tension. The gradient distribution of the inclusion fraction with the maximum value on the surface allows getting higher hardness than the uniform distribution. The size of the reinforcing particles has no great influence, while the volume fraction and type of spatial distribution are of great importance for the mechanical properties considered in this study. It is also shown that boron carbide inclusions serve as a source of crack initiation under mechanical loading.","PeriodicalId":177478,"journal":{"name":"29TH RUSSIAN CONFERENCE ON MATHEMATICAL MODELLING IN NATURAL SCIENCES","volume":"325 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131147662","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}

{"title":"Residual strength estimation of composite three-stringer panel subjected to low-velocity impact","authors":"A. Fedorenko, B. Fedulov, S. Dubinskii, E. Lomakin","doi":"10.1063/5.0059858","DOIUrl":"https://doi.org/10.1063/5.0059858","url":null,"abstract":"The presented research proposes a computational method for conservative residual strength estimation without direct modelling of impact, based on “reversed” topology optimization. To demonstrate basic steps of the method and evaluate its efficiency, the real example of compression after impact (CAI) test of aircraft three-stringer composite panel with quasi-isotropic lay-up is considered. Impact on the skin from the outer side of epy panel leads to damage in all three components of the structure: skin, stringers and noodle. Nondestructive inspection and optical microscopy is used to evaluate dimensions and damage distribution of formed defect after impact for selection of optimization volume in the model. Visually observed damaged zone on stringer and skin dent geometry also used for a conservative selection of optimization volume for the search of the “worst case” damage distribution. Topology optimization procedure shows that the most critical matrix damage distribution is the relatively uniform stiffness reduction of the ±45° layers in a composite layup. Fiber-dominant damage modes appear in 0°-oriented plies next to the noodle. Both matrix and fiber damages are enhanced in the area of stringer noodle due to stress concentration.","PeriodicalId":177478,"journal":{"name":"29TH RUSSIAN CONFERENCE ON MATHEMATICAL MODELLING IN NATURAL SCIENCES","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134084815","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}