Fluid Flow and Transfer Processes, Computational Mechanics, Applied Mathematics, Mechanical Engineering
34
Scopus Publications
Scopus Publications
Numerical Study of Subsonic Hot and Near-Sonic Submerged Jets Based on a Two-Fluid Model Zafar Malikov, Farrukh Nazarov, Sardor Khaydarov Journal of Applied and Computational Mechanics, 2025 This paper discusses the hot subsonic and near-sonic axisymmetric submerged stationary jets flowing from a nozzle with a radius of 25.4 mm. The Mach number at the nozzle exit is 0.376 for a subsonic jet, and for a near-sonic jet, it is 0.985. The Reynolds number for both problems was equal to 5600. A two-fluid turbulence model was used to study these problems. The numerical results of this model were obtained for both the full elliptic and simplified parabolic systems of equations. The SIMPLE procedure was applied to the numerical implementation of the complete elliptic system of equations. In the parabolic system of equations, the marching method of integrating equations in the longitudinal direction is used. The results of the two-fluid model are compared with the results of other known RANS turbulence models, which were obtained using the COMSOL Multiphysics® package, as well as with the experimental data from the NASA database.
Modeling of Turbulent Two-Phase Flow based on a Two-Fluid Approach Z. Malikov, M. Madaliev Journal of Applied and Computational Mechanics, 2025 The paper presents the modeling of two-phase flow in turbulent flow. For this purpose, a two-fluid turbulence model is used. The work can be considered the development of a two-fluid approach to the problem of turbulence, which, unlike Reynolds' approach, leads to a closed system of equations. Therefore, the system of equations for a two-phase flow given in the work based on the two-fluid approach is also closed and no additional hypotheses are required. The resulting system of equations for a turbulent two-phase flow is implemented numerically for a two-phase flow in a cylindrical pipe and in a free jet. The obtained results are compared with known experimental data, as well as with the results of the Reynolds stress method (RSM). The results of the proposed model are in good agreement with experimental data. In addition, it is shown that the model adequately describes the phenomenon of “turbulent migration of particles,” resulting in the accumulation of inertial particles on the axis and wall of the pipe.
Validation of a two-fluid turbulence model in comsol multiphysics for the problem of flow around aerodynamic profiles Z. M. Malikov, M. E. Madaliev, S. L. Chernyshev, A. A. Ionov Scientific Reports, 2024 The article presents a study of a two-fluid turbulence model in the Comsol Multiphysics software package for the problem of a subsonic flow around the DSMA661 and NACA 4412 airfoils with angles of attack of 0 and 13.87 degrees, respectively. In this paper, the finite element method is used for the numerical implementation of the turbulence equations. To stabilize the discretized equations, stabilization by the Galerkin least squares method was used. The results obtained are compared with the results of other RANS, LES, DES models and experimental data. It is shown that in the case of continuous flow around the DSMA661 airfoil, the results of the two-fluid model are very close to the SST results and are in good agreement with the experimental data. When flowing around the NACA 4412 airfoil, flow separation occurs and a recirculation zone appears. It is shown that in such cases the two-fluid model gives more accurate results than other turbulence models. Implementation of the Comsol Multiphysics software package showed good convergence, stability, and high accuracy of the two-fluid turbulence model.
Comparative analysis of turbulence models for calculation of excess velocity and temperature for axisymmetric jet Zafar Malikov, Dilshod Navruzov, Yunus Hamrayev, Takhir Pulatov, Sanjar Juraev Aip Conference Proceedings, 2024 Turbulence models (the k-e Chen model and the two-fluid model) are investigated in the article. Turbulent models are used to study the turbulent heat propagation in a round jet. This problem is of great scientific and practical importance and it is of interest to use the proposed model to predict heat propagation in a round jet. For this, we assume that the pressure is constant. This assumption is well known and it greatly simplifies the calculation procedure. In this case, the system of equations acquires a parabolic type. Therefore, we can use the integration of equations in marching order. For numerical implementation, turbulent models are written in von Mises variables and an implicit scheme of the second order accuracy is used. The numerical results obtained are compared with experimental data from the NASA database. The results are compared for the axial flow velocity profile and temperature distribution. It is shown that the two-fluid model is in better agreement with the experimental data compared with the Chen model. Comparative analysis shows that the two-fluid model is less susceptible to the round jet "anomaly". It is known that many other RANS models give a very strong expansion for axisymmetric jets.
Numerical study of Taylor - Cuetta turbulent flow Zafar M Malikov, Farrux Kholiyorovich Nazarov, Murodil Erkinjan son Madaliev Computer Research and Modeling, 2024 В настоящей работе исследован турбулентный поток Тейлора – Куэтта с помощью двухмерного моделирования на базе осредненных уравнений Навье – Стокса (RANS) и нового двухжидкостного подхода к турбулентности при числах Рейнольдса в диапазоне от 1000 до 8000. Исследуется течение, обусловленное вращающимся внутренним и неподвижным внешним цилиндрами. Рассмотрен случай соотношения диаметров цилиндров 1:2. Известно, что возникающее круговое течение характеризуется анизотропной турбулентностью и математическое моделирование таких потоков является сложной задачей. Для описания таких потоков используются либо методы прямого моделирования, которые требуют больших вычислительных затрат, либо достаточно трудоемкие методырейно льдсовых напряжений или же линейные RANS-модели со специальными поправками на вращение, которые способны описывать анизотропную турбулентность. В работе для сравнения различных подходов к моделированию турбулентности представленычисленны е результатылинейны х RANS-моделей SARC, SST-RC, метода рейнольдсовых напряжений SSG/LRR-RSM-w2012, прямого моделирования турбулентности DNS, а также новой двухжидкостной модели. Показано, что недавно разработанная двухжидкостная модель адекватно описывает рассматриваемый поток. Помимо этого, двухжидкостная модель проста для численной реализации и имеет хорошую сходимость.
NUMERICAL STUDY OF TURBULENT SEPARATED FLOWS IN AXISYMMETRIC DIFFUSERS BASED ON A TWO-FLUID MODEL Bokhodir Kholboev, Zafar M Malikov, Murodil E Madaliev, Mardon Shoev, Sirojiddin Masharipov International Journal of Applied Mechanics and Engineering, 2024 This paper discusses a numerical study of turbulent flow at Re = 1.56×104 in an axisymmetric diffuser with half-angle expansion α=14°, 18° и 90°. The results obtained are compared with known experimental data. The flow at the diffuser inlet is fully developed turbulent. To simulate the flow, a relatively recently developed two-fluid turbulence model in the Comsol Multiphysics software package was used. The paper also presents numerical results of the well-known SST and SA turbulence models, which are included in the Comsol Multiphysics software package. It is shown that the two-fluid turbulence model in the Comsol Multiphysics software package is capable of producing more accurate results than known models. In addition, it demonstrated good convergence and stability.
Bench-scale study of centrifugal fan parameters Anvar Rizaev, Zafar Malikov, Abdurakhim Yuldashev, Davronbek Kuldoshev, Djamaliddin Temirov, Atkham Borotov Iop Conference Series Materials Science and Engineering, 2021
Mathematical modeling of a turbulent flow in a centrifugal separator Academy of Sciences of the Republic of Uzbekistan Institute of Mechanics, Seismic Stability of Structures named after M.T. Urazbayev (Tashkent, Republic of Uzbekistan), Z.M. Malikov, M.E. Madaliev, Fergana Polytechnic Institute (Fergana, Republic of Uzbekistan) Vestnik Tomskogo Gosudarstvennogo Universiteta Matematika I Mekhanika, 2021
NUMERICAL STUDY OF A SWIRLING TURBULENT FLOW THROUGH A CHANNEL WITH AN ABRUBT EXPANSION Institute of Mechanics, Seismic Stability of Structures named after M.T. Urazbayev (Tashkent, Republic of Uzbekistan), Z.M. Malikov, M.E. Madaliev, Fergana Polytechnic Institute (Fergana, Republic of Uzbekistan) Vestnik Tomskogo Gosudarstvennogo Universiteta Matematika I Mekhanika, 2021
