Journal of Thermophysics and Heat Transfer最新文献_第8页

Hybrid Navier–Stokes–Direct Simulation Monte Carlo Automatic Mesh Optimization for Hypersonics 高超声速混合Navier-Stokes-Direct仿真蒙特卡罗自动网格优化

IF 2.1 4区工程技术

Journal of Thermophysics and Heat Transfer Pub Date : 2023-08-25 DOI: 10.2514/1.t6770

Shrutakeerti Mallikarjun, V. Casseau, W. Habashi, Song Gao, A. Karchani

{"title":"Hybrid Navier–Stokes–Direct Simulation Monte Carlo Automatic Mesh Optimization for Hypersonics","authors":"Shrutakeerti Mallikarjun, V. Casseau, W. Habashi, Song Gao, A. Karchani","doi":"10.2514/1.t6770","DOIUrl":"https://doi.org/10.2514/1.t6770","url":null,"abstract":"This paper describes the development of an unstructured hybrid finite element Navier–Stokes (NS)–direct simulation Monte Carlo (DSMC) framework for hypersonic flows. State-based coupling is employed and simulations of varying thermochemical complexity demonstrate the accuracy, robustness, and computational efficiency of the hybrid all-Mach algorithm. An automatic mesh optimization process using a posteriori error estimates based on the Hessian of the solution goes much further than traditional mesh adaptation processes by equidistributing the error estimator and producing a “single optimal hybrid mesh” with no increase in mesh size and with much higher accuracy. The DSMC region cells of the resulting optimal mesh are smaller than in NS regions and are sized to the local mean free path. Mesh optimization is also shown to greatly improve the quality of the hybrid interfaces from those of the initial mesh. Unstructured meshes are found to represent the hybrid interfaces smoothly, while structured meshes showcase a castellated pattern in the interfaces. The optimal hybrid meshes are found to be statistically similar to optimal full DSMC meshes, thus highlighting the solver independence of the optimizer. Such a coupled hybrid mesh optimization strategy can therefore tackle hypersonic flows with multiscale flow features at any degree of rarefaction.","PeriodicalId":17482,"journal":{"name":"Journal of Thermophysics and Heat Transfer","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44785344","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

Effect of Plasma Sheaths on Earth-Entry Magnetohydrodynamics 等离子体鞘层对地球入射磁流体力学的影响

IF 2.1 4区工程技术

Journal of Thermophysics and Heat Transfer Pub Date : 2023-08-11 DOI: 10.2514/1.t6784

B. Parent, Prasanna T. Rajendran, S. Macheret, J. Little, R. W. Moses, C. Johnston, F. Cheatwood

{"title":"Effect of Plasma Sheaths on Earth-Entry Magnetohydrodynamics","authors":"B. Parent, Prasanna T. Rajendran, S. Macheret, J. Little, R. W. Moses, C. Johnston, F. Cheatwood","doi":"10.2514/1.t6784","DOIUrl":"https://doi.org/10.2514/1.t6784","url":null,"abstract":"The first study of the full coupling between the aerothermodynamics, the magnetohydrodynamics (MHD), and the plasma sheaths within Earth-entry flows is here performed. The problem addressed herein is representative of a force-generating MHD patch located between the stagnation point and the aft of a capsule entering the Earth’s atmosphere at Mach 34. The reactions are obtained from the Park chemical solver and the transport coefficients from the Gupta–Yos model with modifications. The physical model fully couples the drift–diffusion model for the sheaths to the multispecies Navier–Stokes equations for the plasma flow. The Hall and ion slip effects are taken into consideration within the plasma flow and within the sheaths. The effect of the electrode material on the MHD process is studied. Using thoriated tungsten instead of graphite leads to a thirtyfold increase in the Lorentz forces and also leads to significantly reduced heat fluxes on the cathode. This is attributed to the much higher electrical conductivity of the thoriated tungsten sheath reducing by orders of magnitude the plasma electrical resistance near the surfaces.","PeriodicalId":17482,"journal":{"name":"Journal of Thermophysics and Heat Transfer","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48066009","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

Analytical Solution for One-Dimensional Transient Thermal Conduction in a Hollow Cylinder 空心圆柱一维瞬态导热的解析解

IF 2.1 4区工程技术

Journal of Thermophysics and Heat Transfer Pub Date : 2023-08-02 DOI: 10.2514/1.t6844

R. McMasters, F. de Monte, Giampaolo D’Alessandro, J. Beck

{"title":"Analytical Solution for One-Dimensional Transient Thermal Conduction in a Hollow Cylinder","authors":"R. McMasters, F. de Monte, Giampaolo D’Alessandro, J. Beck","doi":"10.2514/1.t6844","DOIUrl":"https://doi.org/10.2514/1.t6844","url":null,"abstract":"The primary use of analytical solutions in the area of thermal conduction problems is for verification purposes, comparing the calculated temperatures and heat flux values to the results from numerical codes. The contribution from the analytical solutions can be especially significant where large temperature gradients are found. This is because the temperature and heat flux results can be found very precisely: normally to eight or 10 significant figures using analytical solutions. Normally, numerical solutions require extremely fine grids in high-heat-flux locations, but analytical solutions can provide insight into the adequacy of grid densities in these types of situations. One area of particular interest is in nonrectangular analytical solutions because generalized numerical grids do not naturally lend themselves well to curved surfaces without a large number of nodes. In this current study, four solutions are offered in a geometry involving a hollow cylinder. Two of the solutions examine heating from the inside of the cylinder, and two involve heating from the outside. Development of the solutions is provided along with results that show the temperature responses to the various sets of boundary conditions. A mathematical identity is used as part of the solution, which eliminates the need to evaluate an infinite series, along with need to find roots of transcendental equations and evaluate Bessel functions. Intrinsic verification is also applied in order to provide assurance that the solutions are properly formulated and evaluated.","PeriodicalId":17482,"journal":{"name":"Journal of Thermophysics and Heat Transfer","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45106254","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

Conjugate Heat Transfer in High-Speed External Flows: A Review 高速外流动中的共轭传热研究进展

IF 2.1 4区工程技术

Journal of Thermophysics and Heat Transfer Pub Date : 2023-07-25 DOI: 10.2514/1.t6763

Mikaela T. Lewis, Jean-Pierre Hickey

引用次数: 0

Recurrent Neural Network Flow Rate Modeling of Piezoelectric Injectors in Cooling Testbeds 冷却试验台中压电注射器的递归神经网络流量建模

IF 2.1 4区工程技术

Journal of Thermophysics and Heat Transfer Pub Date : 2023-07-04 DOI: 10.2514/1.t6833

Andrew G. Fordon, Fernando Soria, Yun-Hong Xu, S. Putnam

引用次数: 0

System-Level Impingement Cooling with Cryogens 用冷冻剂进行系统级撞击冷却

4区工程技术

Journal of Thermophysics and Heat Transfer Pub Date : 2023-07-01 DOI: 10.2514/1.t6574

Nicholas Pellizzari, Ryan Touzjian, Andrea Scouras, William P. Flaherty

引用次数: 1

Robust Statistical Approach for Determination of Graphite Nitridation Using Bayesian Model Comparison 用贝叶斯模型比较测定石墨氮化的稳健统计方法

IF 2.1 4区工程技术

Journal of Thermophysics and Heat Transfer Pub Date : 2023-06-19 DOI: 10.2514/1.t6802

K. Miki, R. Upadhyay

{"title":"Robust Statistical Approach for Determination of Graphite Nitridation Using Bayesian Model Comparison","authors":"K. Miki, R. Upadhyay","doi":"10.2514/1.t6802","DOIUrl":"https://doi.org/10.2514/1.t6802","url":null,"abstract":"A better estimation of surface reaction efficiency of semiconductor-grade graphite with atomic nitrogen, as well as the calibration error are calculated using Bayesian updating based on experimental data. Compared with a conventional deterministic model, the stochastic model approach is a powerful tool in the sense that the model is capable of taking into account underlying error correlations among the data quantities. In this paper, we investigate four different stochastic models (called “stochastic system model classes” herein) corresponding to different descriptions of modeling and measurement error structures, given one deterministic physical model. These stochastic system model classes differ in the covariance matrix structure that is used in the uncertainty model to represent uncertainties associated with the physical model and experimental measurements. For each model class, Bayesian inference is used to estimate the posterior probabilities of the physical model parameters as well as of the stochastic model parameters. Model comparison and selection are then applied based on two measures including Bayesian evidence and Bayesian information criterion, as well as the deviance information criterion. Both measures suggest the stochastic model class, which considers that a correlation between errors in two data quantities among different data points is the most plausible. With the stochastic model class, the range of uncertainty in surface reaction efficiency is estimated to be about two orders of magnitude at [Formula: see text].","PeriodicalId":17482,"journal":{"name":"Journal of Thermophysics and Heat Transfer","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43979571","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

Using a Magnetic Field to Reduce Thermocapillary Convection in Thin Annular Pools 利用磁场减少薄环形池中的热毛细对流

IF 2.1 4区工程技术

Journal of Thermophysics and Heat Transfer Pub Date : 2023-06-15 DOI: 10.2514/1.t6832

Mohammed Lamine Moussaoui, B. Mahfoud, Hibet Errahmane Mahfoud

{"title":"Using a Magnetic Field to Reduce Thermocapillary Convection in Thin Annular Pools","authors":"Mohammed Lamine Moussaoui, B. Mahfoud, Hibet Errahmane Mahfoud","doi":"10.2514/1.t6832","DOIUrl":"https://doi.org/10.2514/1.t6832","url":null,"abstract":"This paper presents the investigation of thermocapillary convection in three-dimensional (3-D) thin pools with three cases of annular gaps containing silicon melt under a vertical magnetic field. The model was composed of two vertical walls: the inner is cold, and the outside is hot. Radiation is emitted upward from the free top surface, and the bottom is heated vertically. Both cases are considered in this study, electrically insulating all walls; and only the bottom wall is electrically conducting for three annular gaps. The governing equations were solved numerically through the finite volume method. The effects of different parameters such as the Hartmann number, annular gaps on the temperature distribution, the hydrothermal wave number, and azimuthal patterns, as well as the transition from 3-D steady to axisymmetric flows, were investigated. The results showed three hydrothermal waves are observed in a 3-D steady flow. It was also found that with the increasing Hartmann number, the azimuthal velocity, the temperature fluctuation, and the electric potential decreased. The results also revealed that a stronger magnetic field was needed for the transition from unsteady flow to a nonaxisymmetric steady flow and at the end to steady axisymmetric flow. The findings revealed that electromagnetic damping is more prominent when the bottom wall is electrically conducting than when all walls are insulating.","PeriodicalId":17482,"journal":{"name":"Journal of Thermophysics and Heat Transfer","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46368477","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

Fully Coupled Material Response and Internal Radiative Heat Transfer for Three-Dimensional Heat Shield Modeling 全耦合材料响应和内部辐射传热的三维隔热板建模

IF 2.1 4区工程技术

Journal of Thermophysics and Heat Transfer Pub Date : 2023-06-12 DOI: 10.2514/1.t6699

Raghava S. C. Davuluri, Rui Fu, K. A. Tagavi, Alexandre Martin

{"title":"Fully Coupled Material Response and Internal Radiative Heat Transfer for Three-Dimensional Heat Shield Modeling","authors":"Raghava S. C. Davuluri, Rui Fu, K. A. Tagavi, Alexandre Martin","doi":"10.2514/1.t6699","DOIUrl":"https://doi.org/10.2514/1.t6699","url":null,"abstract":"A material response code is strongly coupled with a radiative transfer equation (RTE) to evaluate the effect of a spectrally resolved heat flux on the thermal response of a heat shield. A [Formula: see text] approximation model of RTE is used to account for radiation heat transfer within the material. First, the RTE model is verified by comparing the numerical results with the analytical solution. Next, the coupling scheme is verified by comparing the temperature histories computed by the pure conduction scheme with the ones computed by conduction coupled with radiative emission. The verification study is conducted using test cases from the literature (radiant heating, arc jet heating, and space shuttle entry) as well as on a 3D Block, a 2D IsoQ sample, and the Stardust Return Capsule. The verification results are satisfactory for all cases. Thus, the verification results indicate that the coupling approach can accurately simulate the thermal response of the material. The coupling scheme was then used to simulate a laser heating experiment that studied the impact of spectral radiative heat transfer on ablative material. The results from the laser ablation simulations exhibit a behavior analogous to the experimental observations, indicating the importance of spectral radiative flux on the material response.","PeriodicalId":17482,"journal":{"name":"Journal of Thermophysics and Heat Transfer","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48025699","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

Innovative Framework for Robustness Analysis of Blade Multicavity Squealer Tip Aerothermal Performance 叶片多腔挤压器叶尖气热性能鲁棒性分析的创新框架

IF 2.1 4区工程技术

Journal of Thermophysics and Heat Transfer Pub Date : 2023-06-01 DOI: 10.2514/1.t6777

Ming Huang, Kai Zhang, Zhigang Li, Jun Li

{"title":"Innovative Framework for Robustness Analysis of Blade Multicavity Squealer Tip Aerothermal Performance","authors":"Ming Huang, Kai Zhang, Zhigang Li, Jun Li","doi":"10.2514/1.t6777","DOIUrl":"https://doi.org/10.2514/1.t6777","url":null,"abstract":"Gas turbines are subject to various geometric and operational uncertainties, which are often overlooked in conventional research. Therefore, conclusions derived from a deterministic approach may not accurately reflect the actual gas turbine operation. To address this issue, this paper presents an effective uncertainty quantification framework for evaluating the aerothermal performance robustness of the multicavity squealer tip. Moreover, a novel visualization method is developed to analyze the uncertainty flow and thermal fields. The findings suggest that conventional research tends to overestimate the aerodynamic performance of the multicavity squealer tip. The installation of ribs can exacerbate the chaotic tendency of the flowfield, leading to a significant reduction in the aerodynamic performance robustness of the squealer tip during actual operation. However, the heat transfer performance robustness of the multicavity squealer tip is substantially enhanced due to the inability of the flowfield uncertainty to transfer to the thermal field through the ribs. Furthermore, the study reveals high heat flux fluctuations in the region near the ribs root, which highlights the importance of considering thermal fatigue risks in the design of multicavity squealer tips.","PeriodicalId":17482,"journal":{"name":"Journal of Thermophysics and Heat Transfer","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45621638","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