Fluid Dynamics最新文献_第7页

Convective Flows of a Colloidal Suspension in a Hele-Shaw Cell under Vertical Vibrations 海尔-肖池内垂直振动下的胶体悬浮液对流

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2024-11-07 DOI: 10.1134/S0015462824602730

I. N. Cherepanov, B. L. Smorodin

引用次数: 0

On the Influence of the Effective Heat of Ablation on Modeling the Interaction of Meteoroids with the Atmosphere 论有效烧蚀热对流星体与大气相互作用建模的影响

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2024-11-07 DOI: 10.1134/S0015462824602742

I. G. Brykina, L. A. Egorova

{"title":"On the Influence of the Effective Heat of Ablation on Modeling the Interaction of Meteoroids with the Atmosphere","authors":"I. G. Brykina, L. A. Egorova","doi":"10.1134/S0015462824602742","DOIUrl":"10.1134/S0015462824602742","url":null,"abstract":"The problem of modeling the entry of a meteoroid into the atmosphere and its interaction with it is considered. The motion, ablation, and energy deposition of a meteoroid or its fragments moving as a single body are modeled within the framework of meteor physics equations. The main parameter of these equations is the ablation parameter, equal to the ratio of the heat transfer coefficient to the effective heat of mass loss. Due to the lack of data from theoretical and experimental studies on the determination of the effective heat of ablation at high meteor velocities, its constant value is usually used in the literature. In this paper, it is proposed to use the effective heat of ablation variable along the trajectory, interpolating its value between the heat of evaporation and the heat of melting (or spallation), depending on the flight velocity. By numerically solving the meteor physics equations, we study the influence of the way of setting the effective heat of ablation and its uncertainty on the simulated characteristics: the meteoroid velocity, as well as the change in its mass and energy deposition along the trajectory and on the trajectory itself; and the inaccuracy in determining these characteristics is evaluated.","PeriodicalId":560,"journal":{"name":"Fluid Dynamics","volume":"59 4","pages":"863 - 874"},"PeriodicalIF":1.0,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142595434","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Numerical Simulation of Vapor Bulk Condensation near the Interfacial Surface under Intensive Evaporation Conditions 密集蒸发条件下界面附近的蒸汽团凝结数值模拟

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2024-11-07 DOI: 10.1134/S0015462824602808

N. M. Kortsenshtein, L. V. Petrov, A. V. Rudov, A. K. Yastrebov

引用次数: 0

Results of Calculations of Detonation Wave Propagation in a Channel with a Hydrogen Gas Mixture 氢气混合物通道中引爆波传播的计算结果

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2024-11-07 DOI: 10.1134/S001546282460278X

A. V. Panasenko

引用次数: 0

Analysis of Two Methods for Estimating the Temperature Dependence of the Gas-Phase Chemical Reaction Rate Constants 气相化学反应速率常数随温度变化的两种估算方法分析

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2024-11-07 DOI: 10.1134/S0015462824602638

M. F. Danilov

{"title":"Analysis of Two Methods for Estimating the Temperature Dependence of the Gas-Phase Chemical Reaction Rate Constants","authors":"M. F. Danilov","doi":"10.1134/S0015462824602638","DOIUrl":"10.1134/S0015462824602638","url":null,"abstract":"In this paper, the issues of the structural-parametric identification of kinetic models intended for the mathematical modeling of physical and chemical processes in gas dynamics are discussed. Two methods to estimate the temperature dependence of the rate constants of gas-phase chemical reactions are analyzed: the standard model based on the well-known Arrhenius formula and a new one proposed relatively recently. The focus of the article is on the basic parameter of the temperature dependence of the rate constants, i.e., the activation energy. The values of activation energy for combustion reactions of a mixture of hydrogen and oxygen that are obtained by approximation of the experimental data based on the Arrhenius formula, calculations based on the theory of the transition state, and values of activation energy obtained using a new model are compared. According to this model, the activation energy for exothermic reactions is always zero, while the activation energy for endothermic reactions is determined by the difference between the potential energies of the final and initial states in the given reaction and is numerically equal to its absolute value. The application of this method for estimating the activation energy is shown to produce results that are in good agreement with the empirical data.","PeriodicalId":560,"journal":{"name":"Fluid Dynamics","volume":"59 4","pages":"875 - 886"},"PeriodicalIF":1.0,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142595351","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Formation of Three-Phase Cavitation Bubbles with Their Own Electric Field in a Hydrophobic Liquid 在疏水性液体中形成自带电场的三相空化气泡

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2024-11-07 DOI: 10.1134/S0015462824603243

A. A. Monakhov

引用次数: 0

Measuring Heat Flux Using Calorimetric Sensors 使用量热传感器测量热通量

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2024-11-07 DOI: 10.1134/S0015462824602754

L. B. Ruleva, S. I. Solodovnikov

引用次数: 0

Modelling of the Process of Volume Annihilation in the Gravitational Self-Field 引力自场中的体积湮灭过程建模

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2024-11-07 DOI: 10.1134/S0015462824603334

A. N. Golubyatnikov, S. A. Zakharov

引用次数: 0

Dynamic Analysis of Deformation of a Droplet on a Uniform Jet Surface 均匀射流表面液滴变形的动态分析

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2024-10-01 DOI: 10.1134/S0015462824600238

H. Zhang, T. F. Zhao

{"title":"Dynamic Analysis of Deformation of a Droplet on a Uniform Jet Surface","authors":"H. Zhang, T. F. Zhao","doi":"10.1134/S0015462824600238","DOIUrl":"10.1134/S0015462824600238","url":null,"abstract":"To address the scientific inquiry regarding the dynamic mechanism of deformation of droplets on the jet surface, this study establishes a stochastic differential equation describing deformation of a droplet on a uniform jet surface, considering the affine deformation of a semi-ellipsoidal droplet driven by the pulsation velocity of the jet. The results indicate that the equilibrium point set of the model conforms to an inverse proportional function concerning the major and minor axes of the droplet. Additionally, the assumption of the physical model is satisfied only when the droplet position parameter (theta in left( {left. {frac{{{pi }}}{2},{{pi }}} right]} right.). The solution process, initialized with the equilibrium point set, tends to reach the state of mean square instability within a very short duration. For dimensionless initial semi-minor axes of the droplet below 0.1 and within the constraint of the equilibrium point set, the probability of the droplet being in a stretched state during the later stages of deformation ranges between 60 and 65%. In this model, during the late stage of droplet deformation, the dimensionless semi-minor axis of the droplet approaches zero. Thus, when the droplet is in the stretched state, it is close to breaking. During retraction, the length of semi-major axis of the droplet fluctuates and gradually decreases. However, in the stretched state, the length of semi-major axis of the droplet increases rapidly, with its growth rate accelerating with time.","PeriodicalId":560,"journal":{"name":"Fluid Dynamics","volume":"59 4","pages":"843 - 857"},"PeriodicalIF":1.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142595382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Wetting and Spreading Characteristics of the Impact of Molten Aluminum Droplets on Surfaces 熔融铝滴冲击表面时的润湿和扩散特性

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2024-10-01 DOI: 10.1134/S0015462824602080

H. M. Sun, Z. Y. Rui, X. Lyu, H. B. Sun, D. Y. He, J. T. Zhuo, Y. Dong

{"title":"Wetting and Spreading Characteristics of the Impact of Molten Aluminum Droplets on Surfaces","authors":"H. M. Sun, Z. Y. Rui, X. Lyu, H. B. Sun, D. Y. He, J. T. Zhuo, Y. Dong","doi":"10.1134/S0015462824602080","DOIUrl":"10.1134/S0015462824602080","url":null,"abstract":"The impact of molten aluminum droplets on a solid surface at a temperature of 1173 K is numerically simulated using the volume of fluid model. The spreading patterns of droplets with various initial velocities and diameters on surfaces with various wettability are investigated, and the velocity distribution, the spreading factor, the height factor, the spreading time, and other parameters of the molten droplets in the impact process are analyzed. The simulation results show that the larger the contact angle, the smaller the wetting radius; the smaller the static contact angle, the smaller the surface and the stronger the droplet adhesion. As the initial velocity of droplet increases, the maximum spreading factor also increases and a jet is generated at the center of droplet. However, change in the initial velocity has a negligible effect on reaching the maximum spreading state. The amplitude and frequency of droplet oscillations increase significantly with the droplet diameter, the smaller droplets deforming faster and stabilizing more easily. Moreover, α is the revised factor in Pasandideh–Fard model based on the energy conservation law. This study aims to provide a theoretical basis for the wetting and spreading adhesion of aluminum liquids in production of electrolytic aluminum.","PeriodicalId":560,"journal":{"name":"Fluid Dynamics","volume":"59 4","pages":"816 - 831"},"PeriodicalIF":1.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142595315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0