{"title":"Effect of working liquid temperature on spray cooling heat transfer","authors":"A. D. Nazarov, N. B. Miskiv","doi":"10.1134/S0869864325060150","DOIUrl":"10.1134/S0869864325060150","url":null,"abstract":"<div><p>The influence of the working liquid (distilled water) temperature of a spray system on heat transfer on a vertical smooth surface without boiling was experimentally studied. During the experiments, a droplet flow was formed using a hydraulic nozzle; the coolant temperature and the specific mass flow of water were varied in the ranges of 13 ÷ 70°C and 3.4 ÷ 4.5 kg/(s·m<sup>2</sup>), respectively. The heat-loaded surface was a stainless-steel foil 20 µm thick with a square working surface of 0.07 × 0.07 m<sup>2</sup>. Heating was carried out using a DC source. The surface heat flux did not exceed 479.6 kW/m<sup>2</sup>. The surface temperature was maintained below 80°C. The study results showed that in a single-phase cooling regime and with an increase in the working fluid temperature to 60°C, the heat transfer coefficient increases in accordance with a dependence close to a linear law. A further increase in water temperature leads to an increase in the temperature of the heat-loaded surface and, consequently, a decrease in heat transfer.</p></div>","PeriodicalId":800,"journal":{"name":"Thermophysics and Aeromechanics","volume":"32 6","pages":"1327 - 1331"},"PeriodicalIF":0.5,"publicationDate":"2026-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148323856","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}
{"title":"Numerical study of disturbance development and transition to turbulence in a supersonic jet","authors":"D. V. Khotyanovsky, A. N. Kudryavtsev","doi":"10.1134/S086986432506006X","DOIUrl":"10.1134/S086986432506006X","url":null,"abstract":"<div><p>Based on a numerical solution of the Navier–Stokes equations, simulations of the development of disturbances and transition to turbulence in an isobaric jet exhausting from a round nozzle have been carried out. The eddy-resolving simulations have been carried out in a three-dimensional setup. Simulation results are compared with available experimental data.</p></div>","PeriodicalId":800,"journal":{"name":"Thermophysics and Aeromechanics","volume":"32 6","pages":"1249 - 1256"},"PeriodicalIF":0.5,"publicationDate":"2026-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148323901","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}
A. A. Ponomarev, A. V. Cherepanov, R. I. Mullyadzhanov, V. M. Dulin
{"title":"Modeling of a flat flame of a methane-air mixture in a longitudinal electric field","authors":"A. A. Ponomarev, A. V. Cherepanov, R. I. Mullyadzhanov, V. M. Dulin","doi":"10.1134/S0869864325060095","DOIUrl":"10.1134/S0869864325060095","url":null,"abstract":"<div><p>A flat flame of a methane-air mixture was numerically simulated in a longitudinal electric field at various fuel/air ratios. A computational code developed in the OpenFOAM based on the reactingParcelFoam solver was used for numerical calculations. The results showed that the predicted value of the ion current correlates with the experimental data. The best agreement is achieved in the lean (<i>φ</i> ≤ 0.8) and rich (<i>φ</i> ≥ 1.3) flames. The greatest discrepancy is recorded for the regime of fuel/air equivalence ratio <i>φ</i> = 0.9. The maximum ion current is achieved at <i>φ</i> = 1.1, which corresponds to the experimental results. The obtained data demonstrate the adequacy of the developed code in predicting the flame current value. Calculation data indicate an increase in CH concentration by 20.5 % and O concentration by 2.0 % when exposed to the electric field; the interaction of these components is the initiating reaction for the formation of charged particles in hydrocarbon flames.</p></div>","PeriodicalId":800,"journal":{"name":"Thermophysics and Aeromechanics","volume":"32 6","pages":"1273 - 1278"},"PeriodicalIF":0.5,"publicationDate":"2026-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148323808","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}
{"title":"Separated flow and heat transfer behind a single rib in an annular gap between rotating cylinders","authors":"T. V. Bogatko, V. V. Terekhov, V. I. Terekhov","doi":"10.1134/S0869864325060010","DOIUrl":"10.1134/S0869864325060010","url":null,"abstract":"<div><p>The results of a numerical study of laminar liquid flow and heat transfer in an annular gap between two cylinders with a rib on one of the walls are presented. A mechanism for intensifying heat transfer between two cylinders, when one is rotating, was studied. Intensification was achieved by installing a single rib on the inner or outer cylinder. The rib was oriented along the annular system radius and occupied half the height of the gap between cylinders. The problem was formulated in two dimensions. The Reynolds number was varied in the range from 100 to 1000. Air was the working medium. Four options for the location of the intensifying rib were considered. A fundamental difference in the structure of the recirculation zone was noted for different rib locations. Maximum heat transfer was achieved on the wall of the stationary cylinder opposite the rib mounted on the rotating cylinder. Its multiple increase was observed compared to the case of rotating smooth cylinders.</p></div>","PeriodicalId":800,"journal":{"name":"Thermophysics and Aeromechanics","volume":"32 6","pages":"1187 - 1193"},"PeriodicalIF":0.5,"publicationDate":"2026-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148323865","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}
{"title":"On a mechanism of controlled disturbances interaction during radiation of acoustic disturbances by a supersonic boundary layer","authors":"A. D. Kosinov, M. V. Piterimova","doi":"10.1134/S0869864325060083","DOIUrl":"10.1134/S0869864325060083","url":null,"abstract":"<div><p>The paper considers the results of hot-wire anemometry for periodic controlled disturbances of mass flow rate beyond the boundary layer on a flat plate. The study gives estimates for wave characteristics that describe the acoustic properties of a supersonic boundary layer. For the first time, we demonstrated an option for emission of subharmonic disturbances at Mach number 2.5.</p></div>","PeriodicalId":800,"journal":{"name":"Thermophysics and Aeromechanics","volume":"32 6","pages":"1267 - 1272"},"PeriodicalIF":0.5,"publicationDate":"2026-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148323870","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}
{"title":"Eigenmode stationary disturbances in a boundary layer of gas flow","authors":"S. A. Gaponov","doi":"10.1134/S0869864325060101","DOIUrl":"10.1134/S0869864325060101","url":null,"abstract":"<div><p>This paper considers stationary disturbances in the boundary layer stability equations for the variants of subsonic and supersonic flow past a plate. For a case of two-dimensional disturbances, theoretical results agree with the available literature data. For the first time, disturbances in a form of longitudinal structures were studied. It was found that the amplitudes of disturbances in longitudinal velocity and temperature over the boundary layer take a bell-shaped profile. This profile has the positions of maximum (in the Dorodnitsyn – Howarth coordinates) which are conservative to variations in the Mach number, Reynolds number and the spanwise wavenumber. Meanwhile, the rate of disturbance dumping along the transversal coordinate and disturbance phase shift over the boundary layer keeps growing with an increase in the listed parameters. The highest change in phase belongs to the lateral velocity parameter.</p></div>","PeriodicalId":800,"journal":{"name":"Thermophysics and Aeromechanics","volume":"32 6","pages":"1279 - 1289"},"PeriodicalIF":0.5,"publicationDate":"2026-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148323871","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}
{"title":"Numerical simulation of ignition of a hydrogen-air mixture in a flow","authors":"V. N. Zudov, O. A. Shmagunov","doi":"10.1134/S0869864325060137","DOIUrl":"10.1134/S0869864325060137","url":null,"abstract":"<div><p>The problem of ignition and combustion of a region expanding over time is considered. Combustion was initiated using a pulsed-periodic energy source. The influence of pulse frequency and flow velocity on ignition was revealed. Autoignition of a laminar hydrogen jet diluted with nitrogen in a co-current heated air flow was numerically simulated. A transient reacting mixing layer between two flows (air and fuel) with different velocities and temperatures was studied.</p></div>","PeriodicalId":800,"journal":{"name":"Thermophysics and Aeromechanics","volume":"32 6","pages":"1305 - 1312"},"PeriodicalIF":0.5,"publicationDate":"2026-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148323867","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}
{"title":"Effect of wettability parameters of the heater porous structure on boiling heat transfer","authors":"A. V. Fedoseev, M. V. Salnikov","doi":"10.1134/S0869864325060125","DOIUrl":"10.1134/S0869864325060125","url":null,"abstract":"<div><p>The effect of wettability parameters of a porous heater material on boiling heat transfer was investigated using a hybrid numerical model based on the lattice Boltzmann method and the heat transfer equation. By simulating the boiling process on a porous heater with a regular hexagonal structure of rectangular metal heat-conducting elements at various thermal loads, boiling curves and coefficients of heat transfer enhancement/degradation were obtained for lyophilic, lyophobic, and neutral heater materials. The results showed that at moderately low thermal loads, the heat transfer coefficient on the lyophobic heater is higher than that for a surface with neutral wettability due to earlier initiation of the vapor phase, while at high thermal loads, heat transfer on the lyophilic heater is the greatest. It was also shown that the temperature of boiling onset is minimal for lyophobic heaters and maximal for lyophilic heaters, and the boiling crisis does not occur on a porous heater of any wettability even at the maximum heat loads considered.</p></div>","PeriodicalId":800,"journal":{"name":"Thermophysics and Aeromechanics","volume":"32 6","pages":"1299 - 1303"},"PeriodicalIF":0.5,"publicationDate":"2026-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148323864","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}
T. S. Korskova, M. A. Zasimova, V. V. Ris, N. G. Ivanov
{"title":"Study of temperature equalization in a ventilated room with air supplied through an oscillator","authors":"T. S. Korskova, M. A. Zasimova, V. V. Ris, N. G. Ivanov","doi":"10.1134/S0869864325060071","DOIUrl":"10.1134/S0869864325060071","url":null,"abstract":"<div><p>The transient effects that develop when supplying intake air to a ventilated space through a fluidic oscillator were numerically studied. The results of parametric two-dimensional URANS simulations in the Reynolds number range of (5.3–53)·10<sup>3</sup> showed that with an increase in the supply flow rate, the frequency of self-oscillations of the supply jet increases linearly, while the Strouhal number varies slightly: from 3.3·10<sup>−3</sup> to 5.4·10<sup>−3</sup>. The use of an oscillator intensifies air mixing significantly compared to the basic case with a stationary air supply through a slot, which provides almost uniform temperature distribution in the room during cooling.</p></div>","PeriodicalId":800,"journal":{"name":"Thermophysics and Aeromechanics","volume":"32 6","pages":"1257 - 1265"},"PeriodicalIF":0.5,"publicationDate":"2026-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148323855","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}
{"title":"Effect of streamwise vortices generated by a jet vortex generator on a characteristic scale of a turbulent shear layer with the diffuser separation","authors":"V. V. Markin, P. A. Polivanov","doi":"10.1134/S0869864325060034","DOIUrl":"10.1134/S0869864325060034","url":null,"abstract":"<div><p>Experiments were conducted on a problem of interaction of streamwise vortices with a turbulent boundary layer and a mixing layer developing in a diffuser. Vortices were generated using jet vortex generators located near the front edge of the diffuser. The majority of measurements were conducted using hot-wire anemometry (HWA) and PIV methods. These experimental methods provide information about flow velocity in the preseparated and separated flow zones and about the dynamic pressure. This allowed for the estimating the turbulent structure scales and parameters of streamwise vortices for different operation regimes of vortex generators. It was observed that a flow with streamwise vortices has a smaller area of separation and this affects significantly the characteristic scale of turbulent structures.</p></div>","PeriodicalId":800,"journal":{"name":"Thermophysics and Aeromechanics","volume":"32 6","pages":"1205 - 1223"},"PeriodicalIF":0.5,"publicationDate":"2026-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148323857","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}