Structure of the nonisothermal swirling gas-droplet flow behind an abrupt tube expansion

Пахомов, М. А.; Терехов, В. И.

doi:10.1134/s0015462816010087

Cited by 8 publications

(3 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The basic phenomena in the context of dispersed flows are spotted in the boundary layer. They lead to the increased intensity of metabolic processes, vortex shedding and turbulent wake formation [8] In order to correctly assess the physical processes in the dispersed boundary layer it is necessary to consider the velocity distribution, the temperatures (non-isothermal condition), and the particle concentration depending on the flow field around the surface and the surface type. The papers [2,9] classify the possible disperse flow field regimes using the Stokes number StK f for the mean motion, which characterizes the velocity relaxation for gasses and particles in the vicinity of the boundary/wall [2].…”

Section: The Theoretical Grounds and Research Metods Of Dispersed Flowsmentioning

confidence: 99%

Mathematical modeling and the study of exchange processes in disperse boundary layer control actions

Bondarenko

Kovalnogov

Fedorov

et al. 2019

Naučn. vestn. MGTU GA

View full text Add to dashboard Cite

A significant interest of researchers is attracted to the effective management and forecasting of exchange processes in the boundary layer, which are key for the implementation of effective and reliable equipment. Modeling of exchange processes occurring in a high-speed dispersed boundary layer with external influences is a very difficult task. Mathematical modeling allows us to develop reliable devices and engines for the fields of aircraft, energy, shipbuilding with minimal costs for its creation. Despite the interest of numerous groups of researchers around the scientific projects and a large number of works, the current theory of the boundary layer is imperfect. This may be due to several circumstances: firstly, the theory of single-phase turbulent flows of continuous media is far from being completed, secondly, turbulent flows with dispersed impurities in the form of particles greatly complicate the already intricate flow pattern. Interest in dispersed flows is particularly relevant due to the fact that almost all gas-dynamic flows contain a certain concentration of particles, and their impact can provoke significant changes in the structure of the boundary layer and affect the intensity of exchange processes. The article proposes a two-fluid mathematical model describing the motion of a high-speed dispersed boundary layer on a surface with hemispherical damping cavities. The use of hemispherical damping cavities allows to reduce turbulent exchange in the boundary layer, which makes it possible to control the intensity of metabolic processes. The possibility of a significant reduction of turbulent heat transfer and friction in the dispersed boundary layer is established. The proposed method of impact on the turbulent transport in the boundary layer will improve the equipment and installations, including GTU and GTE used in various industries of our country, such as energy, aircraft, shipbuilding.

show abstract

Section: The Theoretical Grounds and Research Metods Of Dispersed Flowsmentioning

confidence: 99%

Mathematical modeling and the study of exchange processes in disperse boundary layer control actions

Bondarenko

Kovalnogov

Fedorov

et al. 2019

Naučn. vestn. MGTU GA

View full text Add to dashboard Cite

show abstract

“…A two-phase second-moment turbulent model to numerically simulate the turbulent flow structure, the heat transfer of droplet-laden, gas–droplet, and gas-dispersed particle of separated/swirling flows in sudden expansion pipe was utilized. They found that the fine particle attenuates the gas turbulence up to 25%. , A unified second-order moment particle collision model to depict the anisotropic characteristics of particle, the redistributions of Reynolds stresses of two phases, and the mixing and separation behaviors was proposed . The RANS cannot effectively obtain the coherent structure of turbulent flows and instantaneous velocity information.…”

Section: Introductionmentioning

confidence: 99%

“…They found that the fine particle attenuates the gas turbulence up to 25%. 19,25 A unified secondorder moment particle collision model to depict the anisotropic characteristics of particle, the redistributions of Reynolds stresses of two phases, and the mixing and separation behaviors was proposed. 26 The RANS cannot effectively obtain the coherent structure of turbulent flows and instantaneous velocity information.…”

Section: ■ Introductionmentioning

confidence: 99%

Hydrodynamics of Irregular-Shaped Graphite Particles in Coaxial Two-Phase Jet Flow

Liu

Yong-ju

et al. 2021

ACS Omega

View full text Add to dashboard Cite

Expanded graphite particle is characterized by the low density in comparison with those of bead glass and copper particles. Hydrodynamics of the irregular-shaped graphite particle swirling flows in a coaxial chamber are investigated via an improved kinetic frictional stress model. A drag force coefficient considering the effects of irregular shapes based on the artificial neural network algorithm is adopted to describe the momentum transfer between nonspherical particles and gas phases. The proposed model, algorithm, and source code for modeling and simulation are validated by measurement using spherical glass beads, and acceptable agreement is obtained. Lower sphericity particles enhance the anisotropic particle dispersions and induces the redistributions of the Reynolds stresses of the two-phase flow. Irregular-shaped particles are more sensitive to the gas followability instead of own inertia, whereas spherical particles are easier to be affected by the inlet effects. The interlock force between nonspherical particles takes great effect on particle flow than the spherical particle. The axial–axial normal stresses of sphericities of 0.63 and 0.72 are approximately 3.4 times larger than those of shear stress of spherical particle, and their axial velocities locating at near central regions are 3.0 times larger than those of sphericities.

show abstract

Numerical investigation on mixture particle dispersion characteristics in swirling particle-laden combustion chamber

Liu

Zhang

Chen

et al. 2020

International Communications in Heat and Mass Transfer

View full text Add to dashboard Cite

Structure of the nonisothermal swirling gas-droplet flow behind an abrupt tube expansion

Cited by 8 publications

References 28 publications

Mathematical modeling and the study of exchange processes in disperse boundary layer control actions

Mathematical modeling and the study of exchange processes in disperse boundary layer control actions

Hydrodynamics of Irregular-Shaped Graphite Particles in Coaxial Two-Phase Jet Flow

Numerical investigation on mixture particle dispersion characteristics in swirling particle-laden combustion chamber

Contact Info

Product

Resources

About