Journal of Thermophysics and Heat Transfer最新文献_第10页

Investigation on the Flow Instability of Supercritical Hydrocarbon Fuels in Cooling Channels 超临界碳氢燃料在冷却通道中流动不稳定性的研究

IF 2.1 4区工程技术

Journal of Thermophysics and Heat Transfer Pub Date : 2023-03-10 DOI: 10.2514/1.t6571

Yichao Jin, Kun Wu, Yang Lu, Xuejun Fan

{"title":"Investigation on the Flow Instability of Supercritical Hydrocarbon Fuels in Cooling Channels","authors":"Yichao Jin, Kun Wu, Yang Lu, Xuejun Fan","doi":"10.2514/1.t6571","DOIUrl":"https://doi.org/10.2514/1.t6571","url":null,"abstract":"Flow instability in regenerative cooling channels is an important issue for the thermal protection of hypersonic scramjet engines. Taking into account the dynamic process of the heat transfer and flow instability, a one-dimensional transient model with several modules (including the cracking reaction, convective heat transfer, and rapid calculation of thermal properties) has been developed to investigate the flow instability characteristics of supercritical hydrocarbon fuels in cooling channels. The calculated results were compared and validated against the available experiments and numerical benchmarks, attaining good agreements. By virtue of the transient simulations, the dynamic flow patterns under different flow rates were studied in a single cooling channel with [Formula: see text]-decane being the working substance. Then, the influences of the operating pressure and heated length on the in-tube flow were further investigated. In addition to the Ledinegg instability, several dynamic instability modes were detected under different external driving forces. It was also observed that under a specific range of pressure drop, the in-tube flow could transition from the density-wave oscillation to a new steady state. Moreover, this flow excursion was more likely to be triggered when decreasing the operating pressure or channel length.","PeriodicalId":17482,"journal":{"name":"Journal of Thermophysics and Heat Transfer","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49234960","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

Upstream Endwall Film-Cooing in a Vane Cascade with Cylindrical Shape Holes 圆柱孔叶片叶栅上游端壁膜曲现象

IF 2.1 4区工程技术

Journal of Thermophysics and Heat Transfer Pub Date : 2023-03-09 DOI: 10.2514/1.t6607

B. B. Huyssen, A. S. Shote, G. I. Mahmood

{"title":"Upstream Endwall Film-Cooing in a Vane Cascade with Cylindrical Shape Holes","authors":"B. B. Huyssen, A. S. Shote, G. I. Mahmood","doi":"10.2514/1.t6607","DOIUrl":"https://doi.org/10.2514/1.t6607","url":null,"abstract":"To overcome the disadvantages of cylindrical holes in film cooling, complex geometries of the fan-shaped diffused holes are employed in cascade investigations. The present experiment employs a new design of a diffused hole for film cooling that is formed by diffusing a cylindrical hole smoothly and only in the forward direction. The aerothermal performances in a linear vane cascade are compared between an array of simple cylindrical holes and an array of diffused-cylindrical holes by employing them in the cascade upstream endwall. The objectives are to increase the aerothermal performance of the cylindrical holes in the gas-turbine passage film cooling. The measurements of the temperature, velocity, flow angle, and total-pressure losses are obtained at the inlet Reynolds number of [Formula: see text], as well as the coolant-to-mainstream density ratio of 1.0 and temperature ratios between 0.94 and 1.0. Four inlet blowing ratios of film-cooling flow are tested. The results show less coolant migration into the boundary layer and passage vortex for the diffused holes than for the cylindrical holes. The passage vortex becomes weaker, and the overall total-pressure losses at the passage exit are lower for the diffused holes. The local and average adiabatic film-cooling effectivenesses along the endwall are always higher for the diffused holes.","PeriodicalId":17482,"journal":{"name":"Journal of Thermophysics and Heat Transfer","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47716156","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: 1

Natural Convection Instabilities Using the Lattice Boltzmann Method: Cavity Aspect Ratio Effect 利用晶格玻尔兹曼方法研究自然对流的不稳定性:空腔宽高比效应

IF 2.1 4区工程技术

Journal of Thermophysics and Heat Transfer Pub Date : 2023-03-01 DOI: 10.2514/1.t6690

El Mehdi Berra, M. Faraji

{"title":"Natural Convection Instabilities Using the Lattice Boltzmann Method: Cavity Aspect Ratio Effect","authors":"El Mehdi Berra, M. Faraji","doi":"10.2514/1.t6690","DOIUrl":"https://doi.org/10.2514/1.t6690","url":null,"abstract":"In this paper, the natural convection instability flows in a partial heating cavity filled with air and cooled by the top wall are numerically investigated using the lattice Boltzmann method; and the cavity is partially heated and contains a heat source from below that is presented as an electronic component. To track the cavity aspect ratio effect on the heat transfer over time, first, a series of numerical simulations is completed by varying the aspect ratio of the cavity from [Formula: see text] to [Formula: see text]. The results show that the change in aspect ratio has a noticeable impact on the heat transfer behavior, specifically on the temperature distribution in the cavity, and the numerical results obtained indicate two different temperature distribution regimes: a stable steady regime, and a stable oscillatory regime. In the second step, a numerical simulation is done to study the natural convection instability into the cavity for the aspect ratio configuration of [Formula: see text]. The results show that the cavity structure has an important effect on the heat transfer in the cavity. The lattice Boltzmann method choice as a numerical simulation approach is due to its considerable result in fluid flow simulation and also to its simplicity of implementation, and it has become a suitable alternative method for solving fluid dynamics and thermal problems, as well as challenged traditional methods in many sectors by its simplicity of implementation.","PeriodicalId":17482,"journal":{"name":"Journal of Thermophysics and Heat Transfer","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48245449","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 and Analytical Study on the Liquid Film by Jet–Wall Impingement 射流冲击液膜的实验与分析研究

IF 2.1 4区工程技术

Journal of Thermophysics and Heat Transfer Pub Date : 2023-02-27 DOI: 10.2514/1.t6656

Chuansheng Liu, Chenglong Tang, Qingchen Ma, Zuohua Huang, Peng Zhang, Fengyun Zhang

{"title":"Experimental and Analytical Study on the Liquid Film by Jet–Wall Impingement","authors":"Chuansheng Liu, Chenglong Tang, Qingchen Ma, Zuohua Huang, Peng Zhang, Fengyun Zhang","doi":"10.2514/1.t6656","DOIUrl":"https://doi.org/10.2514/1.t6656","url":null,"abstract":"Liquid film cooling by jet–wall impingement on the combustor wall is commonly used in small rocket engines. The heat transfer mechanism inside the liquid film is closely related to the film flow. Therefore, we establish a comprehensive analytical model with reasonable assumptions for the liquid film flow by inclined jet–wall impingement, and we validate it through a series of experiments. It is found that the predicted liquid film dimensions agree well with the experimental results. As the impingement angle increases from 30 to 60 deg, the shape of the liquid film turns from an oval to a circle. With the increase of the impingement velocity from 7.8 to [Formula: see text], the width, length, and area of the liquid film increase. The wall roughness [Formula: see text] ranges from 6.3 to [Formula: see text], which shows negligible effects on the liquid film dimensions. As the surface tension increases from 36.03 to 67.13 mN/m and the viscosity increases from 1 to [Formula: see text], the dimensions of the liquid film decrease. The effect of viscosity is more significant than surface tension within the scope of this experiment. Finally, an empirical correlation for the three investigated film dimensional parameters is proposed.","PeriodicalId":17482,"journal":{"name":"Journal of Thermophysics and Heat Transfer","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49543558","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: 1

Temperature Rise Characteristics and Experimental Study of Magnetorheological Dampers Under Different Excitations 不同激励下磁流变阻尼器温升特性及实验研究

IF 2.1 4区工程技术

Journal of Thermophysics and Heat Transfer Pub Date : 2023-02-27 DOI: 10.2514/1.t6710

Liang Zhen, Yongbao Feng, Xiaoxia Han, Zhenhua Zhang

{"title":"Temperature Rise Characteristics and Experimental Study of Magnetorheological Dampers Under Different Excitations","authors":"Liang Zhen, Yongbao Feng, Xiaoxia Han, Zhenhua Zhang","doi":"10.2514/1.t6710","DOIUrl":"https://doi.org/10.2514/1.t6710","url":null,"abstract":"The magnetorheological damper converts the mechanical energy of vibration into its own thermal energy, and the thermodynamic energy is expressed as the temperature rise. In this study, according to the principle of temperature rise, the temperature rise of the magnetorheological damper is established theoretical model by using the simplified one-dimensional heat transfer model of a fluid element and the lumped parameter method under the action of sine harmonic wave motion and triangular wave motion, as well as using the finite element software COMSOL to simulate the internal temperature fields of the damper. The results show that the temperature values of the damper are different, there are high-temperature areas and low-temperature areas, and the temperature rise mainly comes from the heating of the coil. The different frequency and amplitude of the excitation signal, as well as the input current, will affect the internal temperature of the damper. The temperature rise increases with the increase of input current, amplitude, and frequency, which is verified on the built testbench for the temperature rise characteristics. The change trend of the theoretical calculated value, the simulated value, and the tested value is consistent; and there is an error within the allowable range. By comparison, the temperature rise trend is basically the same for the three methods; but, when comparing with the application of sine harmonic wave motion, the temperature rise of the magnetorheological damper is 5°C higher than the triangular wave motion under the same operating condition.","PeriodicalId":17482,"journal":{"name":"Journal of Thermophysics and Heat Transfer","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44746059","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

Absolute Measurements of Air Shock-Layer Radiation in the T6 Aluminium Shock Tube T6铝激波管内空气激波层辐射的绝对测量

IF 2.1 4区工程技术

Journal of Thermophysics and Heat Transfer Pub Date : 2023-02-21 DOI: 10.2514/1.t6693

P. Collen, Alex B. Glenn, L. Doherty, M. McGilvray

引用次数: 1

Analysis of Shock Deceleration Effects in the NASA Electric Arc Shock Tube NASA电弧激波管的减震效果分析

IF 2.1 4区工程技术

Journal of Thermophysics and Heat Transfer Pub Date : 2023-02-21 DOI: 10.2514/1.t6619

P. Collen, L. di Mare, M. McGilvray, M. Satchell

{"title":"Analysis of Shock Deceleration Effects in the NASA Electric Arc Shock Tube","authors":"P. Collen, L. di Mare, M. McGilvray, M. Satchell","doi":"10.2514/1.t6619","DOIUrl":"https://doi.org/10.2514/1.t6619","url":null,"abstract":"Complex processes related to nonequilibrium thermochemistry and radiation are a fundamental aspect of atmospheric entry flowfields. Shock tubes provide a means of generating test gas conditions analogous to those found on the stagnation line of flight shock layers, which allows extraction of thermochemical rates and radiative intensities. Currently, the NASA Electric Arc Shock Tube (EAST) is the best source of such data. Although simple in principle, nuances of these experimental facilities can affect the observed results. Notably, electron densities and radiance levels in excess of equilibrium predictions have been observed at EAST for many years. The deceleration of the shock as it passes along the tube has been posited as a source of these discrepancies. In this work, a recently developed numerical methodology (LASTA) is applied to these results from the literature. Using the experimental shock speed profile as an input, trends in postshock electron density are computed. Radiance throughout the shock layer is also predicted by coupling the simulation to the NASA NEQAIR code. It is shown that the predictions of LASTA provide a good match to the magnitudes and trends of the experimental differences, confirming shock speed deceleration as their cause.","PeriodicalId":17482,"journal":{"name":"Journal of Thermophysics and Heat Transfer","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-02-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46060588","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

Computational and Experimental Study of Nonequilibrium Flow in Plasma Wind Tunnel 等离子体风洞中非平衡流动的计算与实验研究

IF 2.1 4区工程技术

Journal of Thermophysics and Heat Transfer Pub Date : 2023-02-12 DOI: 10.2514/1.t6357

V. Unnikrishnan, N. Yadava, N. Virani, J. Ghosh, N. Sreenivas, L. Aravindakshan Pillai, K. Bodi

{"title":"Computational and Experimental Study of Nonequilibrium Flow in Plasma Wind Tunnel","authors":"V. Unnikrishnan, N. Yadava, N. Virani, J. Ghosh, N. Sreenivas, L. Aravindakshan Pillai, K. Bodi","doi":"10.2514/1.t6357","DOIUrl":"https://doi.org/10.2514/1.t6357","url":null,"abstract":"The present work examines the thermochemical nonequilibrium flow in the freestream and shock layer of the Plasma Wind Tunnel Facility using experiments and computations. Computational studies were performed using the open-source solver [Formula: see text], which was validated using the NASA Interaction Heating Facility case. Two chemical reaction models were used to compute the nonequilibrium state of air, composed of six species ([Formula: see text], [Formula: see text], NO, N, O, Ar). Optical emission spectroscopy was employed to experimentally capture the [Formula: see text] first positive system emission from the freestream and molecular CN vibration bands emissions in the shock region. The Boltzmann plot method was employed to estimate the vibrational temperatures from the measured spectra. The measured vibrational temperatures in the freestream for two different transitions of [Formula: see text] agree with one another, which shows that the vibrational modes obey the Boltzmann distribution for the conditions considered in this study. The vibrational temperatures computed using [Formula: see text] in the nozzle freestream and the shock layer for the Plasma Wind Tunnel conditions agree with the values obtained from optical emission spectroscopy.","PeriodicalId":17482,"journal":{"name":"Journal of Thermophysics and Heat Transfer","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43158518","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 Study of Dynamic Icing Process on a Pitot Probe Model 皮托管探针模型动态结冰过程的实验研究

IF 2.1 4区工程技术

Journal of Thermophysics and Heat Transfer Pub Date : 2023-02-01 DOI: 10.2514/1.t6782

Haiyang Hu, Faisal Al-Masri, L. Tian, Hui Hu

{"title":"Experimental Study of Dynamic Icing Process on a Pitot Probe Model","authors":"Haiyang Hu, Faisal Al-Masri, L. Tian, Hui Hu","doi":"10.2514/1.t6782","DOIUrl":"https://doi.org/10.2514/1.t6782","url":null,"abstract":"An experimental study was conducted to characterize the dynamic ice accretion process over the surface of a typical aeronautic Pitot probe model under different icing conditions. The experimental study was conducted in the Icing Research Tunnel available at Iowa State University. While a high-speed imaging system was used to record the dynamic ice accretion process, a three-dimensional (3D) scanning system was also used to measure the 3D shapes of the ice layers accreted on the test model. While opaque and grainy ice structures were found to accrete mainly along the wedge-shaped lip of the front port and over the front surface of the probe holder under a dry rime icing condition, much more complicated ice structures with transparent and glazy appearance were observed to cover almost entire surface of the Pitot probe under a wet glaze icing condition. While a flower-like ice structure was found to grow rapidly along the front port lip, multiple irregular-shaped ice structures accreted over the probe holder under a mixed icing condition. The characteristics of the icing process under different icing conditions were compared in terms of 3D shapes of the ice structures, the profiles of the accreted ice layers, the ice blockage to the front port, and the total ice mass on the Pitot probe model. The acquired ice accretion images were correlated with the 3D ice shape measurements to elucidate the underlying icing physics.","PeriodicalId":17482,"journal":{"name":"Journal of Thermophysics and Heat Transfer","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43295425","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

Mixed-Convection Coupled with Thermal-Radiation in a Ventilated Horizontal Channel Containing Different Electronic Components 含有不同电子元件的通风水平通道中的混合对流与热辐射耦合

IF 2.1 4区工程技术

Journal of Thermophysics and Heat Transfer Pub Date : 2023-01-16 DOI: 10.2514/1.t6659

R. Hidki, L. El moutaouakil, M. Boukendil, Z. Charqui, Z. Zrikem

引用次数: 0