Technical Physics最新文献

{"title":"Vortices Formation and the Condensate Film Surface Shape in Heat Pipes","authors":"A. V. Seryakov","doi":"10.1134/S1063784224700841","DOIUrl":"10.1134/S1063784224700841","url":null,"abstract":"<p>The results of numerical and experimental studies of vortex formation near the condensation surface and the shape of the surface of moving condensate film in short linear heat pipes (HP’s) with a Laval nozzle-liked vapour channel are presented.</p>","PeriodicalId":783,"journal":{"name":"Technical Physics","volume":"69 10","pages":"2583 - 2595"},"PeriodicalIF":1.1,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143404217","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of the Oxide Target Cooling Modes in the Production of Iodine Isotopes","authors":"S. S. Salodkin,&nbsp;Yu. I. Tyurin,&nbsp;V. V. Sokhoreva","doi":"10.1134/S1063784224700816","DOIUrl":"10.1134/S1063784224700816","url":null,"abstract":"<p>To ensure the maximal possible production intensity for iodine-based radiopharmaceuticals, various methods for target cooling (e.g., front-side cooling of ТеО₂ target using air, helium, and fine-dispersed water flow) have been investigated. Using the COMSOL Multiphysics simulation software package, the temperature field of the target cooled by different heat carriers have been compared for the production output of iodine.</p>","PeriodicalId":783,"journal":{"name":"Technical Physics","volume":"69 10","pages":"2574 - 2582"},"PeriodicalIF":1.1,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143404223","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of MHD Heat Exchange in a Liquid Metal Flow through a Tube-in-Channel System under Conditions Close to the Thermonuclear Reactor Blanket Module","authors":"N. A. Luchinkin,&nbsp;N. G. Razuvanov,&nbsp;O. N. Polyanskaya,&nbsp;I. O. Teplyakov","doi":"10.1134/S1063784224700774","DOIUrl":"10.1134/S1063784224700774","url":null,"abstract":"<p>Heat exchange in a liquid metal upward flow through a tube-in-channel system has been studied experimentally and analytically. The system consists of a vertical tube passing along the axis of a square heated channel that is connected to a natural circulation loop. Experiments have been conducted in the presence of a transverse magnetic field and without it. Probe measurements using longitudinal microthermocouple probes placed both in the tube and in the channel gap have been applied. Heat exchange averaged characteristics have been numerically simulated for experimental conditions. Three basic operating conditions of the cooling loop have been considered: the loop is shut off, the loop is open allowing free circulation in the gap without cooling, and the loop is open and provides cooling. In experiments, the profiles of averaged temperature, the distributions of heat transfer local coefficients, and the pulsation characteristics of flow temperature both in the tube and in the channel gap have been obtained. Calculation data have been compared with experimental results. It has been found that the configuration and structure of the flow significantly depend on the presence of transverse magnetic field and on whether the natural circulation loop is connected and provides cooling.</p>","PeriodicalId":783,"journal":{"name":"Technical Physics","volume":"69 9","pages":"2461 - 2471"},"PeriodicalIF":1.1,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143404157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Specific Features of the Breakup of Hot Liquid Metal Droplets Falling into Cold Water","authors":"Yu. P. Ivochkin,&nbsp;S. M. Yudin,&nbsp;T. I. Borodina","doi":"10.1134/S1063784224700828","DOIUrl":"10.1134/S1063784224700828","url":null,"abstract":"<p>The paper presents experimental data of pressure pulses generated by the interaction of liquid Bi, Sn, and Pb with water at room temperature (18°C). The resultant pressure relationships are compared with findings of video recording and with the morphology of crystallized fragmentation products, which allowed to propose an appropriate scenario for the explosive fragmentation process development. Experiments were performed in the ranges of initial temperature and investigated melt mass of 400 to 900°C and 3 to 15 g, respectively. It was confirmed that the explosive fragmentation of hot liquid metal droplets falling into room temperature water produce materials with amorphous structure. It is shown using liquid bismuth as an example that the amorphousness of a material can increase as its volume grows.</p>","PeriodicalId":783,"journal":{"name":"Technical Physics","volume":"69 10","pages":"2517 - 2526"},"PeriodicalIF":1.1,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143404262","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of Subcooled Liquid Jet on the Dynamics of Transition from Steady Film Boiling to Intense Heat Transfer Regime","authors":"T. A. Gubanova,&nbsp;P. K. Kanin,&nbsp;V. V. Yagov,&nbsp;A. R. Zabirov,&nbsp;I. A. Molotova,&nbsp;M. M. Vinogradov","doi":"10.1134/S1063784224700804","DOIUrl":"10.1134/S1063784224700804","url":null,"abstract":"<p>The properties of the cooled surface and of liquid coolant significantly affect the heat transfer intensity during film boiling and the temperature of transition to the intense regime. As a result, many current studies are devoted to unsteady cooling of vertical cylinders and balls made of various metals with and without coating. The impact of an effectively point source of perturbation (such as, for example, a submerged jet) on the vapor film during film boiling is also of genuine interest. This paper presents experimental results of cooling a stainless steel ball in a liquid when exposed to a submerged jet of the same liquid. The aim of the study is to experimentally measure the surface temperature during the transition from steady film boiling to the intense heat transfer regime of boiling. Different cooling liquids were used in the experiments including water, ethanol, water-ethanol mixtures, and perfluorohexane. It is shown that the transition to the intense mode of heat transfer occurs in aqueous liquids significantly earlier than in liquids with high alcohol content. Despite the influence of the submerged jet, there was no intense heat transfer regime during film boiling in perfluorohexane.</p>","PeriodicalId":783,"journal":{"name":"Technical Physics","volume":"69 10","pages":"2510 - 2516"},"PeriodicalIF":1.1,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143404226","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Algorithm of the Search for Inhomogeneities in the Inverse Nonlinear Diffraction Problems","authors":"A. O. Lapich,&nbsp;M. Yu. Medvedik","doi":"10.1134/S1063784224700749","DOIUrl":"10.1134/S1063784224700749","url":null,"abstract":"<p>This study is aimed at the solution of the inverse problem used for determining the inhomogeneity of an object. The scattered field is measured beyond its limits with a certain set of observation points. It is assumed that the radiation source and the observation points are located outside the object under investigation. The scattered field is modeled as the result of solution of the direct problem. For solving the inverse problem, a two-step method is employed. The application of various types of nonlinearities is considered. The computational grid is introduced using the generalized grid method. A numerical method for solving this problem is proposed and implemented. The numerical results reported here demonstrate the solution to the problem for preset experimental data.</p>","PeriodicalId":783,"journal":{"name":"Technical Physics","volume":"69 9","pages":"2454 - 2460"},"PeriodicalIF":1.1,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143404225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of the Efficiency of a Two-Stage Isobutane Heat Pump","authors":"M. S. Purdin,&nbsp;V. V. Yuzyuk","doi":"10.1134/S1063784224700786","DOIUrl":"10.1134/S1063784224700786","url":null,"abstract":"<p>The paper substantiates the relevance of studying the methods for improving the efficiency of heat pumps. Two schemes of two-stage heat pumps and models for them are developed, which permitted calculating the thermal characteristics of cycles. The schemes differ by the presence of a supercooler for condensate. Conclusions are made about the advantages of isobutane as a working fluid over other substances. Maps of modes for the calculated coefficient of thermal transformation are constructed. It is shown that two-stage pumps have a higher coefficient of transformation than single-stage ones. The presence of supercoolers increases the transformation coefficient for both single-stage and two-stage heat pumps. It is found that the coefficient of thermal transformation of the second stage increases with an increase in the temperature difference between the freon temperature at the inlet to the second-stage compressor and the condenser temperature of the second stage.</p>","PeriodicalId":783,"journal":{"name":"Technical Physics","volume":"69 9","pages":"2472 - 2481"},"PeriodicalIF":1.1,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143404198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modification of Polymeric and Composite Materials in Supercritical Fluids","authors":"A. D. Sabirova,&nbsp;R. R. Antipov,&nbsp;T. R. Bilalov","doi":"10.1134/S1063784224700956","DOIUrl":"10.1134/S1063784224700956","url":null,"abstract":"<p>The article presents a brief review of the most important properties of supercritical fluids, in particular, supercritical carbon dioxide. The methods of modification of polymeric and composite materials are considered. Analysis of literature on the methods for materials modification using supercritical fluid media shows their high efficiency of obtaining complex polymer compositions and their processing in order to impart additional properties to them.</p>","PeriodicalId":783,"journal":{"name":"Technical Physics","volume":"69 10","pages":"2571 - 2573"},"PeriodicalIF":1.1,"publicationDate":"2025-02-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143404218","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Calculations on the Interaction of Intense Radiation with Matter in a Magnetic Field","authors":"V. V. Kuzenov,&nbsp;A. A. Normurodov","doi":"10.1134/S1063784224700725","DOIUrl":"10.1134/S1063784224700725","url":null,"abstract":"<p>In the presented article, a qualitative analysis of the plasmadynamic modes of operation of a magnetoplasma compressor (MPC) (specifically, an end-type MPC discharge) is performed. It is shown that the most acceptable mode for optical pumping of gas lasers in the ultraviolet (UV) range of the spectrum is the mode of inhibition of the plasma of the MPC discharge on a gas barrier (ohmic mode). Spatial distributions of plasma parameters are obtained.</p>","PeriodicalId":783,"journal":{"name":"Technical Physics","volume":"69 8","pages":"2379 - 2385"},"PeriodicalIF":1.1,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143108846","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling the Controllability of Performances of Plasmon Graphene Nanoantenna Arrays in the Mid-IR Range","authors":"G. S. Makeeva","doi":"10.1134/S1063784224700737","DOIUrl":"10.1134/S1063784224700737","url":null,"abstract":"<p>The implementation of nanoantennas for optical wireless communications in the infrared (IR) and visible ranges ensures higher data transfer rates, reducing simultaneously the antenna size. The possibility to tune the performances of graphene by chemical doping or bias voltage is relevant in the development of reconfigurable nanoantennas. The goal of this research is the study of the performances (S‑parameters and radiation patterns (RPs)) of plasmonic graphene nanoantenna (PGNA) arrays, their controllability, and the possibility of frequency scanning by changing the chemical potential of graphene (by applying an external electric field) in the mid-IR range. The use of graphene, which has a controlled high electrical conductivity, and plasmonic properties in the terahertz (THz), far-IR and mid-IR ranges is one of the most promising alternatives to noble metals (Au and Ag) as plasmonic materials at optical frequencies only. Modeling the performances of PGNA arrays was carried out using the electrodynamic modeling program CST Microwave Studio 2023, which makes it possible to solve scientific problems associated with the design of graphene antennas in the IR wavelength range. The results of modeling the controllability of the characteristics (S‑parameters, RPs) of a single element of the antenna array (PGNA of rectangular geometry) and PGNA arrays at the resonant frequencies of the fundamental mode of surface plasmon polaritons (SPPs) are obtained, and the possibility of scanning in frequency upon a change in the chemical potential of graphene (by applying an external electric fields) in the mid-IR range is demonstrated. The results of modeling the performances of PGNA arrays show that with an increase in the chemical potential of graphene (in the interval of values of 0.3–1 eV), the operating frequencies are adjusted (frequency scanning) in the mid-IR range, the gain of the PGNA array increases, the RP main lobe narrows, and the RP side lobe level decreases with an increase in the number of single elements (<i>N</i> = 256); and better controllability of the RP main lobe is observed.</p>","PeriodicalId":783,"journal":{"name":"Technical Physics","volume":"69 8","pages":"2386 - 2396"},"PeriodicalIF":1.1,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143108845","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}