Computers & Fluids最新文献_第9页

Energy-consistent discretization of viscous dissipation with application to natural convection flow 粘滞耗散的能量一致离散法在自然对流中的应用

IF 2.5 3区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Fluids

Pub Date : 2024-11-13 DOI: 10.1016/j.compfluid.2024.106473

B. Sanderse , F.X. Trias

A new energy-consistent discretization of the viscous dissipation function in incompressible flows is proposed. It is implied by choosing a discretization of the diffusive terms and a discretization of the local kinetic energy equation and by requiring that continuous identities like the product rule are mimicked discretely. The proposed viscous dissipation function has a quadratic, strictly dissipative form, for both simplified (constant viscosity) stress tensors and general stress tensors. The proposed expression is not only useful in evaluating energy budgets in turbulent flows, but also in natural convection flows, where it appears in the internal energy equation and is responsible for viscous heating. The viscous dissipation function is such that a consistent total energy balance is obtained: the ‘implied’ presence as sink in the kinetic energy equation is exactly balanced by explicitly adding it as source term in the internal energy equation.

Numerical experiments of Rayleigh–Bénard convection (RBC) and Rayleigh–Taylor instabilities confirm that with the proposed dissipation function, the energy exchange between kinetic and internal energy is exactly preserved. The experiments show furthermore that viscous dissipation does not affect the critical Rayleigh number at which instabilities form, but it does significantly impact the development of instabilities once they occur. Consequently, the value of the Nusselt number on the cold plate becomes larger than on the hot plate, with the difference increasing with increasing Gebhart number. Finally, 3D simulations of turbulent RBC show that energy balances are exactly satisfied even for very coarse grids. Therefore, the proposed discretization also forms an excellent starting point for testing sub-grid scale models and is a useful tool to assess energy budgets in any turbulence simulation, with or without the presence of natural convection.

本文提出了不可压缩流动中粘性耗散函数的一种新的能量一致性离散化方法。通过选择扩散项的离散化和局部动能方程的离散化，并要求离散地模仿乘积规则等连续特性，就可以实现这种离散化。对于简化（恒定粘性）应力张量和一般应力张量，所提出的粘性耗散函数具有二次方严格耗散形式。所提出的表达式不仅适用于评估湍流中的能量预算，也适用于自然对流，因为它出现在内能方程中，并负责粘性加热。粘滞耗散函数可以获得一致的总能量平衡：在动能方程中 "隐含 "存在的汇，通过在内能方程中明确加入源项而得到精确平衡。瑞利-贝纳德对流（RBC）和瑞利-泰勒不稳定性的数值实验证实，使用所提出的耗散函数，动能和内能之间的能量交换得到了精确保持。实验进一步表明，粘性耗散并不影响不稳定形成的临界瑞利数，但一旦不稳定发生，粘性耗散会对不稳定的发展产生重大影响。因此，冷板上的努塞尔特数大于热板上的努塞尔特数，随着格布哈特数的增大，两者的差异也会增大。最后，湍流 RBC 的三维模拟结果表明，即使网格非常粗糙，也能完全满足能量平衡的要求。因此，建议的离散化也是测试子网格尺度模型的绝佳起点，是评估任何湍流模拟（无论是否存在自然对流）中能量预算的有用工具。

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引用次数: 0

Gas-kinetic unified algorithm for aerodynamics covering various flow regimes by computable modeling of Boltzmann equation 通过对波尔兹曼方程的可计算建模，实现涵盖各种流动状态的空气动力学气体动力学统一算法

IF 2.5 3区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Fluids

Pub Date : 2024-11-09 DOI: 10.1016/j.compfluid.2024.106472

Zhi-Hui Li , Yong-Dong Liang , Ao-Ping Peng , Jun-Lin Wu , Hao-Gong Wei

The gas-kinetic unified algorithm (GKUA), to solve the modeling of the Boltzmann equation, has been developed to study the aerothermodynamics problems with the effects of wall activation energy covering various flow regimes. The unified velocity distribution function equation could be accordingly presented on the basis of the Boltzmann–Shakhov model. To remove the dependence of the distribution function on velocity space, the conservational discrete velocity ordinate method has been developed for hypervelocity flows. The gas-kinetic finite difference scheme is constructed to directly solve the discrete velocity distribution functions by the operator splitting technique. The discrete velocity numerical integration method with the Gauss-type weight function has been developed to evaluate the macroscopic flow variables. Specially, to model the real physical process between gas molecules and the surface, the Maxwell-type gas-surface interaction model has been presented by the MD (molecular dynamic) simulation to obtain the energy adaptability coefficient. The multi-processing domain decomposition strategy and parallel implementation of high parallel efficiency and expansibility designed for the gas-kinetic numerical method is presented with good load balance and data communication efficiency. To validate the accuracy and feasibility of the present algorithm, the supersonic flows past two-dimensional circular cylinder are simulated covering various flow regimes. The results are in good agreement with the related theoretical, DSMC (Direct Simulation Monte Carlo), N–S (Navier–Stokes), and experimental data. The hypersonic reentry flows with the effects of wall activation energy around the Tianzhou-5 cargo spacecraft are simulated by the present GKUA and the massive parallel strategy. It has been confirmed that the present algorithm from the gas-kinetic point of view probably provides a promising approach to resolve the hypersonic aerothermodynamic problems with the complete spectrum of flow regimes during the re-entry and disintegration of the large-scale spacecraft.

气体动力学统一算法（GKUA）是为了解决波尔兹曼方程的建模问题而开发的，用于研究具有壁面活化能影响的空气热力学问题，涵盖各种流动状态。在波尔兹曼-沙霍夫模型的基础上，可以相应地提出统一的速度分布函数方程。为了消除分布函数对速度空间的依赖，针对超高速流动开发了保守的离散速度序数法。通过算子拆分技术，构建了气体动力学有限差分方案来直接求解离散速度分布函数。开发了带有高斯型权函数的离散速度数值积分方法，用于评估宏观流动变量。特别是，为了模拟气体分子与表面之间的真实物理过程，通过 MD（分子动力学）模拟提出了 Maxwell 型气表相互作用模型，以获得能量适应性系数。为气体动力学数值方法设计的多处理域分解策略和并行执行具有较高的并行效率和扩展性，并具有良好的负载平衡和数据通信效率。为了验证本算法的准确性和可行性，模拟了流经二维圆柱体的超音速气流，涵盖了各种流态。结果与相关理论、DSMC（直接模拟蒙特卡罗）、N-S（纳维-斯托克斯）和实验数据非常吻合。利用本 GKUA 和大规模并行策略模拟了天舟五号货运飞船周围具有壁面活化能影响的高超音速再入流。结果表明，从气体动力学的角度来看，本算法可能为解决大型航天器再入和解体过程中具有完整流态谱的高超声速空气热力学问题提供了一种可行的方法。

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引用次数: 0

The numerical analysis of complete and partial electrocoalescence in the droplet-layer system employing the sharp interface technique for multiphase-medium simulation 采用尖锐界面技术对液滴层体系中的完全和部分电凝聚进行多相中模拟的数值分析

IF 2.5 3区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Fluids

Pub Date : 2024-11-09 DOI: 10.1016/j.compfluid.2024.106478

Grigorii Yagodin, Ilia Elagin, Sergei Vasilkov, Vladimir Chirkov

In this paper, the coalescence of a drop of water suspended in oil with a layer of water under the influence of a constant electric field is numerically investigated. Unlike most existing studies, the calculations are based on the application of the arbitrary Lagrangian-Eulerian method (ALEM), also called the moving mesh method, which belongs to the class of methods for modeling two-phase liquids with a sharp interface. Using this approach made it possible to avoid a false "escape" of the surface charge from the interface, which often occurs when using methods involving a diffuse interface. Despite the fact that ALEM does not allow describing topology changes by default, a numerical model was implemented in which the calculation is divided into three parts: the convergence of the drop and the layer before the moment of touch; the manual construction of the bridge at the moment of touch; the union of the drop and the layer. The developed model allowed us to obtain three possible modes of this process: complete coalescence, partial coalescence and a mode of stretching which has not practically been considered yet. The dependence of the volume of the separated secondary droplet on the size of the initial droplet and the average intensity of the applied electric field is obtained. The model showed good quantitative agreement with experimental studies. It has been shown that generally, the spots where the bridge and the neck are formed in case of partial coalescence do not coincide. A map of coalescence modes was obtained, i.e., the dependence of the transition threshold from coalescence to partial coalescence and from partial coalescence to stretching regime in a wide range of radii of initial droplets and electric field strengths. It has been shown that there is a maximum field strength at which droplets of any size merge with the layer. This map makes it possible to predict the coalescence regime in electrocoalescer. The proposed modeling technique can be used to calculate electrocoalescence modes at various values of the main parameters, which will help to optimize electrocoalescers at the design stage.

本文对悬浮在油中的水滴在恒定电场影响下与水层的凝聚进行了数值研究。与大多数现有研究不同，计算基于任意拉格朗日-欧勒方法（ALEM）的应用，该方法也称为移动网格法，属于具有尖锐界面的两相液体建模方法。使用这种方法可以避免表面电荷从界面 "逃逸 "的错误现象，这种现象在使用涉及扩散界面的方法时经常出现。尽管 ALEM 默认情况下不允许描述拓扑结构的变化，但我们还是建立了一个数值模型，将计算分为三个部分：在接触瞬间之前液滴和液层的汇聚；在接触瞬间手动构建桥梁；液滴和液层的结合。根据所建立的模型，我们可以得出这一过程的三种可能模式：完全聚合、部分聚合和一种尚未实际考虑过的拉伸模式。分离的次级液滴的体积与初始液滴的大小和外加电场的平均强度有关。该模型与实验研究显示出良好的定量一致性。研究表明，在部分凝聚的情况下，形成桥和颈的点一般并不重合。获得了凝聚模式图，即在初始液滴半径和电场强度的广泛范围内，从凝聚到部分凝聚以及从部分凝聚到拉伸机制的过渡阈值的相关性。结果表明，存在一个最大电场强度，在该强度下，任何大小的液滴都会与层合并。该图使得预测电凝聚器中的凝聚机制成为可能。所提出的建模技术可用于计算不同主要参数值下的电凝聚模式，这将有助于在设计阶段优化电凝聚器。

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引用次数: 0

Numerical investigation on the end effects of the flow past a finite rotating circular cylinder with two free ends 关于流经带两个自由端有限旋转圆柱体的末端效应的数值研究

IF 2.5 3区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Fluids

Pub Date : 2024-11-06 DOI: 10.1016/j.compfluid.2024.106475

Qiliang Liu, Shuguang Gong, Haishan Lu, Guilan Xie, Zhijian Zuo

This paper studies the impact of the aspect ratio and free end shape on the end effects in the flow past a rotating circular cylinder with two flat, radiused, hemispherical, and conical ends, using the large eddy simulation method at a Reynolds number of

4.6 \times 10^{4}

. The aspect ratio in the range of 6–30 and the rotation rate in the range of 0–3, are investigated. The results show that the mean drag coefficient initially decreases slightly before rapidly increasing with the rotation rate, with a critical rotation rate that rises from 1 to 1.5 as the aspect ratio increases from 6 to 30. In contrast, the mean lift coefficient increases with both the rotation rate and the aspect ratio. When the rotation rate increases and the aspect ratio decreases, the differences between the aerodynamic coefficients of the four end shapes become more pronounced. The flat end results in the highest mean drag and lift coefficients, while the hemispherical end yields the lowest ones. In addition, when the rotation rate increases, the alternate shedding vortices shift to the opposite side. They even disappear and increase the elongated streamwise vortices. Due to the combined impacts of the rotation and end effects, large-scale tip vortices are formed, significantly altering the wake structure. The intense rotation effect results in expanding the strong influence region of the end effects and shrinking (or even removing) the weak influence region.

本文在雷诺数为 4.6×104 的条件下，采用大涡度模拟方法研究了长宽比和自由端形状对流过具有两个平端、半球形端和锥形端旋转圆柱体的末端效应的影响。研究了 6-30 范围内的长宽比和 0-3 范围内的旋转率。结果表明，随着长宽比从 6 增加到 30，临界旋转率从 1 上升到 1.5。相比之下，平均升力系数会随着旋转率和纵横比的增加而增加。当旋转率增加而纵横比减小时，四种端部形状的空气动力系数之间的差异变得更加明显。扁平端产生的平均阻力系数和升力系数最高，而半球形端产生的平均阻力系数和升力系数最低。此外，当旋转速度增加时，交替脱落的漩涡会转向另一侧。它们甚至消失并增加了拉长的流向涡流。在旋转效应和末端效应的共同作用下，形成了大尺度的尖端涡，显著改变了尾流结构。强烈的旋转效应导致末端效应的强影响区扩大，弱影响区缩小（甚至消失）。

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引用次数: 0

On correctly evaluating orders of truncation error for node-centered edge-based schemes 关于正确评估基于节点中心边缘方案的截断误差阶数

IF 2.5 3区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Fluids

Pub Date : 2024-11-05 DOI: 10.1016/j.compfluid.2024.106470

Cosimo Tarsia Morisco, Hiroaki Nishikawa

In this short note, we present a simple analysis to show that an observed order of truncation error on a regular grid can change, if not correctly evaluated, depending on the choice of the norm and also on the discretization scheme. For a second-order scheme, it can be first order, second order, or anywhere in between. Using the node-centered edge-based discretization as an example, we provide a guide on how to evaluate the order of truncation error correctly: one should evaluate it separately for a set of nodes, where the residual stencil is symmetric and the same at every node, and the rest of nodes.

在这篇短文中，我们通过一个简单的分析表明，在常规网格上观察到的截断误差阶数，如果没有得到正确的评估，会随着规范的选择和离散化方案的不同而发生变化。对于二阶方案，它可以是一阶、二阶或介于两者之间的任何一阶。以以节点为中心的基于边缘的离散化为例，我们为如何正确评估截断误差的阶数提供了指导：我们应该分别评估一组节点和其他节点的截断误差，前者的残余模版是对称的，并且在每个节点上都是相同的。

引用次数: 0

Non-inertial computational framework for long-distance shock-driven object dynamics 长距离冲击驱动物体动力学的非惯性计算框架

IF 2.5 3区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Fluids

Pub Date : 2024-11-05 DOI: 10.1016/j.compfluid.2024.106474

Dagao Wang , Guilai Han , Meikuan Liu , Zongxian Li

In the realm of dynamic separation problems, the motion of a body triggered by shock interactions is a common phenomenon. This is particularly important in terms of the safe separation of two-stage-to-orbit vehicles, where the motion must remain stable despite long-distance disturbances from shock waves. The flow field in these cases is complex, marked by interactions between hypersonic shock waves and a moving boundary. This leads to significant unsteady effects due to the body's translation and rotation over extended distances. Existing simulation techniques fall short in rapidly and accurately predicting the aerodynamic force and thermal properties for these problems, largely due to the overwhelming computational demands that result from oversize computational domains and the necessity of grid deformation. This paper presents a novel non-deforming grid method to address these challenges. The central concept is to anchor the reference frame to the moving object itself and to approach the problem from a non-inertial frame perspective. This accounts for the motion of the object solely via the inertial source term, circumventing the complexities of mesh manipulation typically required to link flow and motion equations. The moving shock boundary is designed to be closely compatible with selected shock-captured schemes, which reduces non-physical oscillations compared to the traditional method of direct assembly with theoretical shock relations. Other boundary conditions and the solution process are also refined to specifically target the unsteady, shock-dominated flow. These modifications significantly alleviate the computational burden. The effectiveness of the proposed method is demonstrated through several test cases. To showcase the method's practical application, a scenario is simulated wherein an ellipse is dislodged from a wedge by an incident shock wave, covering a long distance. These tests confirm the method's feasibility in aerospace engineering problems.

在动态分离问题领域，由冲击相互作用引发的物体运动是一种常见现象。这对于两级入轨飞行器的安全分离尤为重要，因为在这种情况下，尽管受到冲击波的长距离干扰，运动仍必须保持稳定。这些情况下的流场非常复杂，其特点是高超音速冲击波与运动边界之间的相互作用。由于机体在长距离内的平移和旋转，这导致了严重的不稳定效应。现有的模拟技术无法快速准确地预测这些问题的气动力和热特性，这主要是由于过大的计算域和网格变形的必要性导致了过高的计算要求。本文提出了一种新颖的非变形网格方法来应对这些挑战。其核心理念是将参考框架锚定在运动物体本身，并从非惯性框架的角度来处理问题。这种方法仅通过惯性源项来考虑物体的运动，从而避免了连接流动方程和运动方程通常所需的复杂网格操作。移动冲击边界的设计与选定的冲击捕获方案密切兼容，与直接装配理论冲击关系的传统方法相比，减少了非物理振荡。其他边界条件和求解过程也进行了改进，以专门针对以冲击为主的非稳定流。这些修改大大减轻了计算负担。通过几个测试案例证明了所提方法的有效性。为了展示该方法的实际应用，我们模拟了一个椭圆被入射冲击波从楔形中移开，并覆盖很长一段距离的场景。这些测试证实了该方法在航空航天工程问题中的可行性。

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引用次数: 0

Reduced data-driven turbulence closure for capturing long-term statistics 减少数据驱动的湍流闭合，捕捉长期统计数据

IF 2.5 3区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Fluids

Pub Date : 2024-11-01 DOI: 10.1016/j.compfluid.2024.106469

Rik Hoekstra , Daan Crommelin , Wouter Edeling

We introduce a simple, stochastic, a-posteriori, turbulence closure model based on a reduced subgrid scale term. This subgrid scale term is tailor-made to capture the statistics of a small set of spatially-integrated quantities of interest (QoIs), with only one unresolved scalar time series per QoI. In contrast to other data-driven surrogates the dimension of the “learning problem” is reduced from an evolving field to one scalar time series per QoI. We use an a-posteriori, nudging approach to find the distribution of the scalar series over time. This approach has the advantage of taking the interaction between the solver and the surrogate into account. A stochastic surrogate parametrization is obtained by random sampling from the found distribution for the scalar time series. We compare the new method to an a-priori trained convolutional neural network on two-dimensional forced turbulence. Evaluating the new method is computationally much cheaper and gives similar long-term statistics.

我们引入了一个简单的随机后验湍流闭合模型，该模型基于一个缩小的子网格尺度项。这种子网格尺度项是专门为捕捉一小部分空间整合的相关量（QoIs）的统计数据而设计的，每个 QoIs 只有一个未解决的标量时间序列。与其他数据驱动的代用指标相比，"学习问题 "的维度从一个不断变化的场缩小到每个 QoI 一个标量时间序列。我们采用后验、推导的方法来寻找标量序列随时间的分布。这种方法的优点是将求解器与代用参数之间的相互作用考虑在内。从找到的标量时间序列分布中随机抽样，即可得到随机代用参数。我们将新方法与先验训练的卷积神经网络在二维强迫湍流上进行了比较。评估新方法的计算成本要低得多，而且能得到相似的长期统计数据。

引用次数: 0

On an explicit method for pre-estimate flux for incompressible flow simulation 关于不可压缩流动模拟通量预估的显式方法

IF 2.5 3区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Fluids

Pub Date : 2024-10-28 DOI: 10.1016/j.compfluid.2024.106458

Shumian Zhao , Bernhard Stoevesandt , Joachim Peinke

For incompressible Computational Fluid Dynamics (CFD) problems, the finite volume method (FVM) often uses explicit velocity flux to linearise the convection term. This makes the convergence sensitive to the initial velocity field. The pre-estimation of the initial field is a common strategy to stabilise and/or speed up the solving process. A common technique is to pre-solve a potential flow problem. Here we present an alternative method to pre-estimate the initial flow field for incompressible flow problems. The method will be based on explicit cell-wise flux balancing combined with face shear corrections. This distinguishes it from a typical potential flow pre-estimation where no viscous effects are considered. We will also demonstrate the effectiveness of the method in terms of increasing the convergence speed of CFD simulations on the popular open source platform OpenFOAM in both 2d and 3d scenarios.

对于不可压缩计算流体动力学（CFD）问题，有限体积法（FVM）通常使用显式速度通量来线性化对流项。这使得收敛性对初始速度场非常敏感。预估初始场是稳定和/或加快求解过程的常用策略。预求解势流问题是一种常用技术。在这里，我们将介绍一种预估不可压缩流动问题初始流场的替代方法。该方法基于明确的单元通量平衡，并结合面剪切修正。这使它有别于不考虑粘性效应的典型势流预估。我们还将在流行的开源平台 OpenFOAM 上演示该方法在提高二维和三维 CFD 模拟收敛速度方面的有效性。

引用次数: 0

Modal and nonmodal global instabilities of rotating incompressible axisymmetric boundary layer 旋转不可压缩轴对称边界层的模态和非模态全局不稳定性

IF 2.5 3区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Fluids

Pub Date : 2024-10-28 DOI: 10.1016/j.compfluid.2024.106459

Ramesh Bhoraniya , Mayank Thummar , Zahir Hussain

This study discusses the modal and non-modal global instabilities of the boundary layer produced on a rotating circular cylinder. An investigation was conducted on a flow of in-compressible fluid over a rotating cylinder of fixed length. The rotation effect of a cylinder generates pressure gradient and centrifugal force radially. The Reynolds number (Re) and rotation rate (S) were calculated using the cylinder’s radius. The Spectral collocation approach discretizes the 3D stability equations in cylindrical polar coordinates, resulting in an initial value problem. Computations were performed for azimuthal wave numbers, N = 0, 1, 2, and 3, Re = 2600, 5200, and 20800, and S = 0.0, 0.5, 1.0, and 2.0. The transient energy growth (

G (t)

) and optimal disturbances were computed by appropriately superimposing the global modes. The perturbation structure that maximizes

G (t)

has been analyzed. The S enhances the optimal value of

G (t)

for a specific Re and N. The highest

G (t)

was observed for helical mode

N = 1

at low Re and for axisymmetric mode

N = 0

at higher Re. The disturbances’ spatial structure has been elongated in the shear direction and has grown and intensity as

S

and

R e

have increased. The perturbation structures are qualitatively distinct for

N = 0

and

N = 1

. The energy budget components have been notably impacted by the alterations in the base-flow caused by the influence of

S

.

本研究讨论了旋转圆筒上产生的边界层的模态和非模态全局不稳定性。研究对象是固定长度的旋转圆柱体上的不可压缩流体流。圆柱体的旋转效应在径向产生压力梯度和离心力。利用圆柱体的半径计算了雷诺数（Re）和旋转率（S）。光谱配位法将三维稳定方程离散到圆柱极坐标中，从而产生一个初值问题。计算的方位角波数为 N = 0、1、2 和 3，Re = 2600、5200 和 20800，S = 0.0、0.5、1.0 和 2.0。通过适当叠加全局模式，计算出瞬态能量增长（G(t)）和最佳扰动。分析了最大化 G(t) 的扰动结构。在低 Re 条件下，螺旋模式 N=1 的 G(t) 最大，而在高 Re 条件下，轴对称模式 N=0 的 G(t) 最大。扰动的空间结构在剪切方向上被拉长，并随着 S 和 Re 的增大而增强。扰动结构在 N=0 和 N=1 时有本质区别。由于 S 的影响，基流发生了变化，能量收支成分受到了明显的影响。

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引用次数: 0

A high-order local correlation based transition model for transonic airfoil flows 基于高阶局部相关性的跨音速翼面流过渡模型

IF 2.5 3区工程技术 Q3 COMPUTER SCIENCE, INTERDISCIPLINARY APPLICATIONS

Computers & Fluids

Pub Date : 2024-10-28 DOI: 10.1016/j.compfluid.2024.106461

Matthias Plath , Florent Renac , Olivier Marquet , Christian Tenaud

Accurate transition modeling is a key ingredient towards the all-time goal of improved aerodynamic performance in the aircraft industry. While several different approaches exist to model transition, local correlation based transition models (LCTM) are one of the most versatile strategies. Many versions of LCTM were proposed in the context of lower order finite volume discretizations, but so far only a few transition models have been brought to higher-order numerical schemes. The present work represents a first attempt of including a one equation LCTM into the high-order discontinuous Galkerin (DG) framework. Several modifications are accessed to improve the model’s robustness and tailor it for transonic airfoil flows. Validation is conducted for a series of test cases, starting with zero pressure gradient flat plates, progressing through high Reynolds number airfoil flows, and concluding with a complex unsteady transonic buffet scenario. All results are compared against experiments and previous numerical references.

精确的过渡建模是飞机工业实现提高气动性能这一全时目标的关键要素。虽然有几种不同的过渡建模方法，但基于局部相关性的过渡模型（LCTM）是最通用的策略之一。在低阶有限体积离散化的背景下提出了许多版本的 LCTM，但迄今为止，只有少数过渡模型被引入到高阶数值方案中。本研究首次尝试将单方程 LCTM 纳入高阶非连续加尔克里林（DG）框架。为了提高模型的鲁棒性并使其适合跨音速机翼流，我们对模型进行了一些修改。对一系列测试案例进行了验证，从零压力梯度平板开始，到高雷诺数机翼流，最后是复杂的非稳态跨声速缓冲情景。所有结果都与实验和以前的数值参考资料进行了比较。

引用次数: 0