Thermophysics and Aeromechanics最新文献_第4页

Plasma technology for producing hydrogen and carbon black from hydrocarbon gases 利用烃类气体生产氢气和炭黑的等离子技术

IF 0.5 4区工程技术

Thermophysics and Aeromechanics Pub Date : 2024-12-13 DOI: 10.1134/S086986432403017X

V. E. Messerle, A. B. Ustimenko

引用次数: 0

Numerical investigation of entropy generation induced by assisted mixed convection in a vertical convergent channel: effects of geometric parameters 垂直辐合通道中辅助混合对流诱导熵产的数值研究：几何参数的影响

IF 0.5 4区工程技术

Thermophysics and Aeromechanics Pub Date : 2024-12-13 DOI: 10.1134/S0869864324030211

A. Abidi-saad, S. Hadjadj, S. Saouli, G. Polidori

{"title":"Numerical investigation of entropy generation induced by assisted mixed convection in a vertical convergent channel: effects of geometric parameters","authors":"A. Abidi-saad, S. Hadjadj, S. Saouli, G. Polidori","doi":"10.1134/S0869864324030211","DOIUrl":"10.1134/S0869864324030211","url":null,"abstract":"<div><p>In this paper, the analysis of the 2nd law of thermodynamics characteristics of assisted mixed convection heat transfer coupled with fluid flow within a vertical convergent isothermal channel is numerically carried out. The numerical model is undertaken for 2D, laminar and steady flow using finite volume approach and air as working fluid. The analysis focused on two pertinent geometric situations namely the variation of the minimal distance (<i>D</i><sub>min</sub>) of the convergent channel while keeping the convergence angle fixed, and the change of the latter (2°, 10°, and 20°) while <i>D</i><sub>min</sub> kept unchanged. Whereas, <i>D</i><sub>max</sub> was used as the characteristic length. The measurements are performed for the following buoyancy-assisted cases: upward/downward flow within hot/cold walls. Several buoyancy parameters are considered ranging from 0.1 to 10 at Reynolds number equal to 100. The effect the aforementioned geometric parameters on entropy production and its distribution is investigated. The results revealed that the energy degradation is dominated by heat transfer irreversibility. Also, this latter is more influenced by <i>D</i><sub>min</sub> variations.</p></div>","PeriodicalId":800,"journal":{"name":"Thermophysics and Aeromechanics","volume":"31 3","pages":"599 - 617"},"PeriodicalIF":0.5,"publicationDate":"2024-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142821407","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

Investigating the contact thermal resistances of lead in a heat conducting sublayer 研究导热子层中铅的接触热阻

IF 0.5 4区工程技术

Thermophysics and Aeromechanics Pub Date : 2024-12-13 DOI: 10.1134/S0869864324030119

A. B. Kruglov, V. I. Rachkov, I. G. Merinov, V. S. Kharitonov, L. P. Paredes

引用次数: 0

Effect of reduced frequency on kinematics of self-excited oscillations for a conical-spherical body at Mach number M = 1.75 降低频率对马赫数 M = 1.75 时锥球体自激振荡运动学的影响

IF 0.5 4区工程技术

Thermophysics and Aeromechanics Pub Date : 2024-12-13 DOI: 10.1134/S0869864324030053

E. A. Chasovnikov

引用次数: 0

Experimental study of the action of weak shock waves on the boundary layer flow on a swept flat plate at the Mach number 2 马赫数为 2 时弱冲击波对掠过平板上边界层流动作用的实验研究

IF 0.5 4区工程技术

Thermophysics and Aeromechanics Pub Date : 2024-12-13 DOI: 10.1134/S0869864324030077

A. D. Kosinov, N. V. Semionov, A. V. Shmakova, A. A. Yatskikh

引用次数: 0

Experimental research of Cr-Ag coatings prepared by magnetron sputtering and electroplating for ITER thermal shield 通过磁控溅射和电镀制备用于国际热核聚变实验堆热屏蔽的铬-银涂层的实验研究

IF 0.5 4区工程技术

Thermophysics and Aeromechanics Pub Date : 2024-12-13 DOI: 10.1134/S0869864324030223

W. Liu, Sh. Huang, Sh. Du, C. Chen, X. Chen

{"title":"Experimental research of Cr-Ag coatings prepared by magnetron sputtering and electroplating for ITER thermal shield","authors":"W. Liu, Sh. Huang, Sh. Du, C. Chen, X. Chen","doi":"10.1134/S0869864324030223","DOIUrl":"10.1134/S0869864324030223","url":null,"abstract":"<div><p>The Cr-Ag coating was prepared by electroplating and magnetron sputtering on 6061 aluminum alloy matrix to balance the thermal shield radiation shielding capability and the coating performance for the International Thermonuclear Experimental Reactor (ITER) project. The microstructure, adhesion, and thermal shielding properties of the coating were analyzed. The results show that the Cr-Ag magnetron sputtering coating has flat surface, and better thickness uniformity than electroplate coating. The adhesion force of the Cr-Ag magnetron sputtering coating is 1.56 times higher than that electroplating coating, which is 53 N. The emissivity test results show that the emissivity of Cr-Ag coating by magnetron sputtering method at 80 K is 0.018, much lower than the emissivity of electroplating coating and 6061 aluminum alloy matrix. Theoretical calculation of radiant heat load based on emissivity test shows that the thermal shielding effect of Cr-Ag coating on thermal shield surface by magnetron sputtering is better than that of other groups. The results are of great significance for the combination of coating properties with broader thermal shield properties.</p></div>","PeriodicalId":800,"journal":{"name":"Thermophysics and Aeromechanics","volume":"31 3","pages":"619 - 629"},"PeriodicalIF":0.5,"publicationDate":"2024-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142821409","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

On the parabolization of equations for the propagation of small disturbances in two-dimensional boundary layers 论二维边界层小扰动传播方程的抛物线化

IF 0.5 4区工程技术

Thermophysics and Aeromechanics Pub Date : 2024-12-13 DOI: 10.1134/S0869864324030016

A. V. Boiko, K. V. Demyanko, G. V. Zasko, Yu. M. Nechepurenko

引用次数: 0

Computational study of the processes of pulverized coal oxygen combustion in a vortex burner 涡旋燃烧器中煤粉氧燃烧过程的计算研究

IF 0.5 4区工程技术

Thermophysics and Aeromechanics Pub Date : 2024-12-13 DOI: 10.1134/S0869864324030156

V. A. Kuznetsov, D. M. Bozheeva, A. A. Dekterev, A. V. Minakov

引用次数: 0

Passive control of shock wave/turbulent boundary layer interaction using low permeability wall ventilation over a supercritical RAE-2822 airfoil 超临界RAE-2822翼型上采用低渗透壁面通风的激波/湍流边界层相互作用被动控制

IF 0.5 4区工程技术

Thermophysics and Aeromechanics Pub Date : 2024-12-13 DOI: 10.1134/S086986432403020X

C. Zater, L. Bahi

{"title":"Passive control of shock wave/turbulent boundary layer interaction using low permeability wall ventilation over a supercritical RAE-2822 airfoil","authors":"C. Zater, L. Bahi","doi":"10.1134/S086986432403020X","DOIUrl":"10.1134/S086986432403020X","url":null,"abstract":"<div><p>The effect of a passive control concept made of a porous surface with a cavity underneath the shock wave/boundary layer interaction on a supercritical RAE-2822 airfoil in a transonic flow regime, is investigated to achieve a better efficiency using a variable porous length with a low permeability factor. A numerical approach is carried out using the commercial ANSYS Fluent code to solve the Reynolds-averaged Navier–Stokes equations of a two-dimensional, fully turbulent, compressible, and steady flow around the airfoil at M<sub>∞</sub> = 0.82, Re<sub>∞</sub> = 2·10<sup>7</sup>, and a 6° angle of attack, with the Spalart–Allmaras turbulence model. Both cases of a clean and a porous configuration, have been studies. The results showed the effect of the control technique by producing a downstream movement of the shock with a larger flow supersonic region and a reduced flow separation zone and thus a weaker SBLI, compared to the clean. Consequently, a lift increase and a drag reduction are obtained, leading to an improvement in the aerodynamic efficiency. Seeking for a higher control efficiency, variable porous surface lengths and low permeability factors, have been tested. The best aerodynamic efficiency was obtained with a full-chord porosity and a low permeability factor of 10<sup>−6</sup>, with an appreciable gain in lift of 47 % and a substantial net drag reduction of 65 %.</p></div>","PeriodicalId":800,"journal":{"name":"Thermophysics and Aeromechanics","volume":"31 3","pages":"583 - 597"},"PeriodicalIF":0.5,"publicationDate":"2024-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142821408","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

Experimental investigation of thermal distribution on an airfoil wing coated with nanomaterials in a supersonic flow 超声速流动中纳米涂层翼型机翼热分布的实验研究

IF 0.5 4区工程技术

Thermophysics and Aeromechanics Pub Date : 2024-12-13 DOI: 10.1134/S0869864324030193

L. Kasi, P. Thangavelu

{"title":"Experimental investigation of thermal distribution on an airfoil wing coated with nanomaterials in a supersonic flow","authors":"L. Kasi, P. Thangavelu","doi":"10.1134/S0869864324030193","DOIUrl":"10.1134/S0869864324030193","url":null,"abstract":"<div><p>The thermal instability experienced by aircraft beyond supersonic speeds poses a significant risk to structural stability, particularly due to airfoil surface delamination. Conventional methods of addressing this issue involve incorporating thermal shields and modifying the design, but these approaches require extensive redesigning and lack scalability. However, an alternative approach is to reduce surface temperature distribution and minimize surface drag through the application of nanomaterial coatings. In this study, graphene nanocoating was utilized to reduce the surface roughness of the TsAGI S-12 airfoil. The thermal characteristics of the coated airfoil were evaluated using infrared (IR) imaging. The results of wind tunnel experiments showed a remarkable 21 % reduction in surface temperature and an 18 % reduction in shock wave angle compared to the conventional airfoil. Additionally, atomic force microscopy (AFM) analysis of the coated nanomaterial surface revealed a decrease in surface roughness from 20 nm to 2 nm. The use of nanomaterial surface coatings proves to be a simple and highly effective method for reducing surface temperature and minimizing shockwaves. Moreover, it offers the advantage of high scalability, making it easily applicable in the aircraft industry. Ultimately, the application of nanomaterial coatings has the potential to revolutionize the supersonic aviation industry by enhancing stability and performance.</p></div>","PeriodicalId":800,"journal":{"name":"Thermophysics and Aeromechanics","volume":"31 3","pages":"563 - 582"},"PeriodicalIF":0.5,"publicationDate":"2024-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142821411","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