Thermophysics and Aeromechanics最新文献_第3页

Engineering a loop thermosyphon with 3D-printed developed microstructured surface of the evaporator

IF 0.5 4区工程技术

Thermophysics and Aeromechanics Pub Date : 2025-03-12 DOI: 10.1134/S0869864324040085

Yu. V. Lyulin, M. M. Afonin, D. G. Firsov, S. A. Evlashin, A. V. Dedov

引用次数: 0

Analytical and numerical modeling of the composite “hydrocarbon – water” drop heating

IF 0.5 4区工程技术

Thermophysics and Aeromechanics Pub Date : 2025-03-12 DOI: 10.1134/S0869864324040103

I. V. Derevich, D. I. Matyukhina

{"title":"Analytical and numerical modeling of the composite “hydrocarbon – water” drop heating","authors":"I. V. Derevich, D. I. Matyukhina","doi":"10.1134/S0869864324040103","DOIUrl":"10.1134/S0869864324040103","url":null,"abstract":"<div><p>Analytical and numerical solutions for the heating of a composite “hydrocarbon–water” drop with a water micro-droplet located in the center of a spherical drop of hydrocarbon are compared. The conjugation conditions are fulfilled at the interface: continuity of temperature and heat flux. At the outer boundary of the droplet, a condition of heat exchange with a hot gas streamlining the droplet is set. The analytical formula is based on the decomposition of the solution in a series of eigenfunctions of the Sturm–Liouville problem. An original conservative difference scheme for the numerical integration of the equations of thermal conductivity inside a composite droplet is constructed to take into account the abrupt change in thermophysical properties at the interface of hydrocarbon–water media. The calculation results obtained using the analytical formula and the numerical integration method are consistent with each other. The numerical scheme includes radiative heat transfer and the effect of evaporation on the heat transfer coefficient. A comparison of the simulation results with experimental data is presented.</p></div>","PeriodicalId":800,"journal":{"name":"Thermophysics and Aeromechanics","volume":"31 4","pages":"729 - 740"},"PeriodicalIF":0.5,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143594624","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

Manipulating liquid-liquid flow with magnetic dispersed phase in a T-junction microchannel using a constant magnetic field

IF 0.5 4区工程技术

Thermophysics and Aeromechanics Pub Date : 2025-03-12 DOI: 10.1134/S0869864324040140

A. V. Kovalev, A. A. Yagodnitsyna, A. V. Bilsky

引用次数: 0

Control of self-oscillations of a round turbulent jet propagating in a narrow rectangular cavity

IF 0.5 4区工程技术

Thermophysics and Aeromechanics Pub Date : 2025-03-12 DOI: 10.1134/S0869864324040176

M. A. Zasimova, A. D. Krasikova, N. G. Ivanov

引用次数: 0

Features of nitrogen boiling dynamics on microstructured porous coatings 微结构多孔涂层上的氮沸腾动力学特征

IF 0.5 4区工程技术

Thermophysics and Aeromechanics Pub Date : 2024-12-13 DOI: 10.1134/S0869864324030107

D. V. Kuznetsov, A. N. Pavlenko

引用次数: 0

Experimental study of the influence of supersonic boundary-layer suction on its stability to controlled disturbances 超音速边界层吸力对受控扰动稳定性影响的实验研究

IF 0.5 4区工程技术

Thermophysics and Aeromechanics Pub Date : 2024-12-13 DOI: 10.1134/S0869864324030041

V. I. Lysenko, B. V. Smorodsky, Yu. G. Yermolaev, S. N. Tagaev, A. D. Kosinov

引用次数: 0

Numerical simulation of effective turbulent heat transfer at transverse streamlining of a rod bundle 杆束横向流线处有效湍流传热的数值模拟

IF 0.5 4区工程技术

Thermophysics and Aeromechanics Pub Date : 2024-12-13 DOI: 10.1134/S0869864324030065

M. V. Bayaskhalanov, I. G. Merinov, M. I. Pisarevskiy, V. S. Kharitonov, A. E. Aksenova, V. A. Pervichko, V. V. Chudanov

引用次数: 0

Experimental study of interfacial mass transfer for the transition from slug to bubbly flow in a rectangular microchannel 矩形微通道中从蛞蝓流向气泡流的界面传质实验研究

IF 0.5 4区工程技术

Thermophysics and Aeromechanics Pub Date : 2024-12-13 DOI: 10.1134/S0869864324030144

G. V. Bartkus, N. A. Filatov, A. S. Bukatin, V. V. Kuznetsov

{"title":"Experimental study of interfacial mass transfer for the transition from slug to bubbly flow in a rectangular microchannel","authors":"G. V. Bartkus, N. A. Filatov, A. S. Bukatin, V. V. Kuznetsov","doi":"10.1134/S0869864324030144","DOIUrl":"10.1134/S0869864324030144","url":null,"abstract":"<div><p>The structure of a gas-liquid flow and interfacial mass transfer during the transition from the slug to the bubbly flow of ethanol-CO<sub>2</sub> mixture in a horizontal straight microchannel were experimentally studied. The experiments were performed for a channel with a rectangular cross section of 141×385 µm in the range of superficial gas and liquid velocities <i>J</i><sub><i>G</i></sub> = 0.16–0.8 m/s and <i>J</i><sub><i>L</i></sub> = 0.22–0.5 m/s. To determine a change in the volume of the elongated bubble along the microchannel length due to CO<sub>2</sub> absorption, the method of high-speed visualization with subsequent image processing was applied. The bubble frequency, velocity, size, and change in the volume of gas slugs and bubbles along the channel were measured, and volumetric coefficient of mass transfer from liquid <i>k</i><sub>L</sub><i>a</i> was calculated. The measured volumetric mass transfer coefficient was compared with the known correlations and a new correlation was proposed for the transition from the slug to the bubbly flow due to interfacial mass transfer.</p></div>","PeriodicalId":800,"journal":{"name":"Thermophysics and Aeromechanics","volume":"31 3","pages":"513 - 522"},"PeriodicalIF":0.5,"publicationDate":"2024-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142821423","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

Stability of a high-speed boundary layer over a plate with graphite coating sublimation 带有石墨涂层升华的板上高速边界层的稳定性

IF 0.5 4区工程技术

Thermophysics and Aeromechanics Pub Date : 2024-12-13 DOI: 10.1134/S0869864324030028

S. A. Gaponov, B. V. Smorodsky

{"title":"Stability of a high-speed boundary layer over a plate with graphite coating sublimation","authors":"S. A. Gaponov, B. V. Smorodsky","doi":"10.1134/S0869864324030028","DOIUrl":"10.1134/S0869864324030028","url":null,"abstract":"<div><p>The paper presents results of a theoretical study for parameters of a compressible boundary layer for the case of a re-entry space vehicle flying in atmosphere with the free flow at Mach 6 ≤ M ≤ 10 with sublimation of the carbon coating (graphite). Since a high flight velocity results in a higher wall temperature and a higher mass loss rate, the effect of wall material evaporation decreases the wall temperature as compared with the case of zero-sublimation flow. All that increases the gas mixture density in the sublimation vapor cloud nearby the wall; this is beneficial for stability of the high-speed boundary layer in the response to the first-mode disturbance. As for the second mode disturbances, the lower values of spatial amplification rate with increasing Mach number is observed due to the surface material sublimation. The position of laminar-turbulent transition was evaluated using the <i>e</i><sup><i>N</i></sup> method. Our computations demonstrated that (for a flow with M = 6) the surface sublimation has no influence for laminar-turbulent transition; this transition is governed by the growth of three-dimensional (3D) first mode disturbances. At higher Mach numbers (for M = 8 and higher) we observe that the disturbance amplification rate in the downstream direction becomes smaller. The transition is driven by a 2D second mode. The graphite coating sublimation has destabilizing influence for the second mode; that accelerates the boundary layer transition to turbulence.</p></div>","PeriodicalId":800,"journal":{"name":"Thermophysics and Aeromechanics","volume":"31 3","pages":"411 - 429"},"PeriodicalIF":0.5,"publicationDate":"2024-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142821437","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

A method for determining the heat and mass transfer efficiency in a film cooling tower with intensified fill packs 确定带强化填料的薄膜冷却塔传热和传质效率的方法

IF 0.5 4区工程技术

Thermophysics and Aeromechanics Pub Date : 2024-12-13 DOI: 10.1134/S0869864324030090

A. G. Laptev, E. A. Lapteva

{"title":"A method for determining the heat and mass transfer efficiency in a film cooling tower with intensified fill packs","authors":"A. G. Laptev, E. A. Lapteva","doi":"10.1134/S0869864324030090","DOIUrl":"10.1134/S0869864324030090","url":null,"abstract":"<div><p>A modified method of transfer units is developed for a countercurrent film cooling tower with a structured tubular packing with surface intensifiers in order to determine the thermal efficiency of the gas and liquid phases and the temperature of the cooled water at the output. The approach of presenting the number of transfer units, taking into account additional terms with reverse mixing coefficients is applied to indirectly consider the hydrodynamic structure of flows and a decrease in the heat and mass transfer efficiency, compared with the ideal displacement model. An experimental installation with a layout (column) of a Plexiglass cooling tower with a diameter of 200 mm and a height of 2 m is described. Experimental data for water cooling in a structured packing block in the form of a vertical bundle of tightly packed polyethylene pipes with a diameter of 0.05 m with an annular discretely structured surface roughness are presented. Generalized calculated empirical expressions for the drag of dry and irrigated pipes, as well as the dependence of the volumetric mass transfer coefficient on air velocity at different irrigation densities, are obtained. The parameters of expression of the modified number of transfer units are identified based on experimental data on thermal efficiency in the gas phase. As a result, the dependence of the thermal efficiency in the gas phase on the pressure and design characteristics of the structured packing is obtained taking into account the reverse mixing of the flows. Reverse mixing is shown to reduce thermal efficiency by 8 – 15 %, which must be taken into account in the calculations of film cooling towers. The calculation results for the SK-400 industrial cooling tower using the presented expressions are provided and the agreement of the thermal efficiency of the cooling tower with the calculation according to the proposed method is shown.</p></div>","PeriodicalId":800,"journal":{"name":"Thermophysics and Aeromechanics","volume":"31 3","pages":"469 - 479"},"PeriodicalIF":0.5,"publicationDate":"2024-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142821431","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