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Dynamic stall control over a rotor airfoil based on AC DBD plasma actuation Adv. Aerodyn. Pub Date : 2021-03-02 Guangyin Zhao; Yong Huang; Yongdong Yang; Guoqiang Li; Hesen Yang
At present, the control capability of dielectric barrier discharge (DBD) plasma actuation covers the flow velocity range of helicopter’s retreating blades, so it is necessary to extend it to the dynamic stall control of rotor airfoils. A DBD plasma actuator was adopted to control the dynamic stall of an oscillating CRA309 airfoil in this paper. The effectiveness of alternating current (AC) DBD plasma
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Progress of discrete unified gas-kinetic scheme for multiscale flows Adv. Aerodyn. Pub Date : 2021-02-06 Zhaoli Guo; Kun Xu
Multiscale gas flows appear in many fields and have received particular attention in recent years. It is challenging to model and simulate such processes due to the large span of temporal and spatial scales. The discrete unified gas kinetic scheme (DUGKS) is a recently developed numerical approach for simulating multiscale flows based on kinetic models. The finite-volume DUGKS differs from the classical
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Inverse design of mesoscopic models for compressible flow using the Chapman-Enskog analysis Adv. Aerodyn. Pub Date : 2021-02-02 Tao Chen; Lian-Ping Wang; Jun Lai; Shiyi Chen
In this paper, based on simplified Boltzmann equation, we explore the inverse-design of mesoscopic models for compressible flow using the Chapman-Enskog analysis. Starting from the single-relaxation-time Boltzmann equation with an additional source term, two model Boltzmann equations for two reduced distribution functions are obtained, each then also having an additional undetermined source term. Under
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Drag reduction by application of aerodynamic devices in a race car Adv. Aerodyn. Pub Date : 2021-01-28 Devang S. Nath; Prashant Chandra Pujari; Amit Jain; Vikas Rastogi
In this era of fast-depleting natural resources, the hike in fuel prices is ever-growing. With stringent norms over environmental policies, the automotive manufacturers are on a voyage to produce efficient vehicles with lower emissions. High-speed cars are at a stake to provide uncompromised performance but having strict rules over emissions drives the companies to approach through a different route
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mSwap: a large-scale image-compositing method with optimal m-ary tree Adv. Aerodyn. Pub Date : 2021-01-27 Min Hou; Chongke Bi; Fang Wang; Liang Deng; Gang Zheng; Xiangfei Meng
With the increasing of computing ability, large-scale simulations have been generating massive amounts of data in aerodynamics. Sort-last parallel rendering is the most classical image compositing method for large-scale scientific visualization. However, in the stage of image compositing, the sort-last method may suffer from scalability problem on large-scale processors. Existing image compositing
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A conceptual design for deflection device in VTDP system Adv. Aerodyn. Pub Date : 2020-11-26 Yongwei Gao; Jianming Zhang; Long Wang; Bingzhen Chen; Binbin Wei
The effectiveness of the Vectored Thrust Ducted Propeller (VTDP) system is not high currently, especially the lateral force is not large enough. Thus, a conceptual design for a deflection device of a VTDP system was proposed to achieve effective hovering control. The magnitude of the lateral force that was applied to maintain balance while hovering was examined. A comparison between the experimental
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A reconstructed discontinuous Galerkin method for compressible flows on moving curved grids Adv. Aerodyn. Pub Date : 2021-01-08 Chuanjin Wang; Hong Luo
A high-order accurate reconstructed discontinuous Galerkin (rDG) method is developed for compressible inviscid and viscous flows in arbitrary Lagrangian-Eulerian (ALE) formulation on moving and deforming unstructured curved meshes. Taylor basis functions in the rDG method are defined on the time-dependent domain, where the integration and computations are performed. The Geometric Conservation Law (GCL)
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Wall pressure beneath a transitional hypersonic boundary layer over an inclined straight circular cone Adv. Aerodyn. Pub Date : 2020-12-14 Siwei Dong; Jianqiang Chen; Xianxu Yuan; Xi Chen; Guoliang Xu
Properties of wall pressure beneath a transitional hypersonic boundary layer over a 7∘ half-angle blunt cone at angle of attack 6∘ are studied by Direct Numerical Simulation. The wall pressure has two distinct frequency peaks. The low-frequency peak with f≈10−50 kHz is very likely the unsteady crossflow mode based on its convection direction, i.e. along the axial direction and towards the windward
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Numerical study on the influence of initial ambient temperature on the aerodynamic heating in the tube train system Adv. Aerodyn. Pub Date : 2020-12-08 Shijie Bao; Xiao Hu; Jukun Wang; Tianhao Ma; Yingyu Rao; Zigang Deng
The evacuated tube transportation has great potential in the future because of its advantages of energy saving and environmental protection. The train runs in the closed tube at ultra-high speed. The heat quantity generated by aerodynamic heating is not easy to spread to external environment and then accumulates in the tube, inducing the ambient temperature in the tube to rise gradually. In this paper
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High order semi-implicit weighted compact nonlinear scheme for the all-Mach isentropic Euler system Adv. Aerodyn. Pub Date : 2020-11-26 Yanqun Jiang; Xun Chen; Xu Zhang; Tao Xiong; Shuguang Zhou
The computation of compressible flows at all Mach numbers is a very challenging problem. An efficient numerical method for solving this problem needs to have shock-capturing capability in the high Mach number regime, while it can deal with stiffness and accuracy in the low Mach number regime. This paper designs a high order semi-implicit weighted compact nonlinear scheme (WCNS) for the all-Mach isentropic
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Large-eddy simulation of wall-bounded turbulent flow with high-order discrete unified gas-kinetic scheme Adv. Aerodyn. Pub Date : 2020-11-26 Rui Zhang; Chengwen Zhong; Sha Liu; Congshan Zhuo
In this paper, we introduce the discrete Maxwellian equilibrium distribution function for incompressible flow and force term into the two-stage third-order Discrete Unified Gas-Kinetic Scheme (DUGKS) for simulating low-speed turbulent flows. The Wall-Adapting Local Eddy-viscosity (WALE) and Vreman sub-grid models for Large-Eddy Simulations (LES) of turbulent flows are coupled within the present framework
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Extending the global-direction stencil with “face-area-weighted centroid” to unstructured finite volume discretization from integral form Adv. Aerodyn. Pub Date : 2020-11-17 Lingfa Kong; Yidao Dong; Wei Liu; Huaibao Zhang
Accuracy of unstructured finite volume discretization is greatly influenced by the gradient reconstruction. For the commonly used k-exact reconstruction method, the cell centroid is always chosen as the reference point to formulate the reconstructed function. But in some practical problems, such as the boundary layer, cells in this area are always set with high aspect ratio to improve the local field
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The shape of incident shock wave in steady axisymmetric conical Mach reflection Adv. Aerodyn. Pub Date : 2020-10-31 Yu-xin Ren; Lianhua Tan; Zi-niu Wu
For internal flow with supersonic inflow boundary conditions, a complicated oblique shock reflection may occur. Different from the planar shock reflection problem, where the shape of the incident shock can be a straight line, the shape of the incident shock wave in the inward-facing axisymmetric shock reflection in steady flow is an unknown curve. In this paper, a simple theoretical approach is proposed
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A sharp-interface immersed boundary method for simulating high-speed compressible inviscid flows Adv. Aerodyn. Pub Date : 2020-10-20 Junjie Wang; Xiangyu Gu; Jie Wu
This paper presents a robust sharp-interface immersed boundary method for simulating inviscid compressible flows over stationary and moving bodies. The flow field is governed by Euler equations, which are solved by using the open source library OpenFOAM. Discontinuities such as those introduced by shock waves are captured by using Kurganov and Tadmor divergence scheme. Wall-slip boundary conditions
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Correction to: High-enthalpy hypersonic flows Adv. Aerodyn. Pub Date : 2020-09-15 Joseph J. S. Shang; Hong Yan
An amendment to this paper has been published and can be accessed via the original article.
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A unified gas-kinetic scheme for micro flow simulation based on linearized kinetic equation Adv. Aerodyn. Pub Date : 2020-09-03 Chang Liu; Kun Xu
The flow regime of micro flow varies from collisionless regime to hydrodynamic regime according to the Knudsen number Kn, which is defined as the ratio of the mean free path over the local characteristic length. On the kinetic scale, the dynamics of a small-perturbed micro flow can be described by the linearized kinetic equation. In the continuum regime, according to the Chapman-Enskog theory, hydrodynamic
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The thermochemical non-equilibrium scale effects of the high enthalpy nozzle Adv. Aerodyn. Pub Date : 2020-08-10 Junmou Shen; Hongbo Lu; Ruiqu Li; Xing Chen; Handong Ma
The high enthalpy nozzle converts the high enthalpy stagnation gas into the hypervelocity free flow. The flow region of the high enthalpy nozzle consists of three parts: an equilibrium region upstream of the throat, a non-equilibrium region near the throat, and a frozen region downstream of the throat. Here we propose to consider the thermochemical non-equilibrium scale effects in the high enthalpy
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High-enthalpy hypersonic flows Adv. Aerodyn. Pub Date : 2020-08-07 Joseph J. S. Shang; Hong Yan
Nearly all illuminating classic hypersonic flow theories address aerodynamic phenomena as a perfect gas in the high-speed range and at the upper limit of continuum gas domain. The hypersonic flow is quantitatively defined by the Mach number independent principle, which is derived from the asymptotes of the Rankine-Hugoniot relationship. However, most hypersonic flows encounter strong shock-wave compressions
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An improved WENO-Z scheme with symmetry-preserving mapping Adv. Aerodyn. Pub Date : 2020-08-01 Zheng Hong; Zhengyin Ye; Kun Ye
Since the classical weighted essentially non-oscillatory (WENO) scheme is proposed, various improved versions have been developed, and a typical one is the WENO-Z scheme. Although better resolution is achieved, it is shown in this article that, the result of WENO-Z scheme suffers evident distortion in the long-time simulation of the linear advection equation. In order to fix the problem of WENO-Z,
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Hybrid grid generation for viscous flow simulations in complex geometries Adv. Aerodyn. Pub Date : 2020-07-30 Hongfei Ye; Yang Liu; Bo Chen; Zhiwei Liu; Jianjing Zheng; Yufei Pang; Jianjun Chen
In this paper, we present a hybrid grid generation approach for viscous flow simulations by marching a surface triangulation on viscous walls along certain directions. Focuses are on the computing strategies used to determine the marching directions and distances since these strategies determine the quality of the resulting elements and the reliability of the meshing procedure to a large extent. With
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Influence of rotor solidity on trailing edge noise from wind turbine blades Adv. Aerodyn. Pub Date : 2020-06-29 Vasishta Bhargava Nukala; Satya Prasad Maddula
Noise prediction from streamlined bodies such as wind turbine blades can be predicted accurately using CFD computations that use spatio-temporal turbulence models at the expense of high computational power. In this work, empirical methods proposed from BPM, Grosveld and Lowson are used to compute numerically to analyse the influence of rotor solidity factor on broadband trailing edge noise from a 2 MW
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Correction to: Aerodynamics and dynamic stability of micro-air-vehicle with four flapping wings in hovering flight Adv. Aerodyn. Pub Date : 2020-06-28 Cheng Cheng; Jianghao Wu; Yanlai Zhang; Han Li; Chao Zhou
An amendment to this paper has been published and can be accessed via the original article.
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Effects of aspect ratio and inclination angle on aerodynamic loads of a flat plate Adv. Aerodyn. Pub Date : 2020-06-19 Mehrdad Shademan; Arash Naghib-Lahouti
Large Eddy Simulations are carried out to analyze flow past flat plate in different configurations and inclinations. A thin flat plate is considered at three inclination angles (α = 30°, 60° and 90°) and three aspect ratios (AR = 0.5, 2 and 5). The Reynolds number based on the free stream velocity and chord length of the plate at different inclination angles varies between 75,000 to 150,000. An increase
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A three-dimensional gas-kinetic flux solver for simulation of viscous flows with explicit formulations of conservative variables and numerical flux Adv. Aerodyn. Pub Date : 2020-05-26 Y. Sun; L. M. Yang; C. Shu; C. J. Teo
A truly three-dimensional (3D) gas-kinetic flux solver for simulation of incompressible and compressible viscous flows is presented in this work. By local reconstruction of continuous Boltzmann equation, the inviscid and viscous fluxes across the cell interface are evaluated simultaneously in the solver. Different from conventional gas-kinetic scheme, in the present work, the distribution function
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ILES of an array of three subsonic counter-flow jets issuing from a wing leading edge exposed to hypersonic aerodynamic heating Adv. Aerodyn. Pub Date : 2020-05-08 Tomonori Shimada; Taku Ohwada
The flow of an active thermal protection system exploiting subsonic counter-flow jets for wing leading edges of hypersonic vehicles is numerically studied on the basis of the three dimensional Navier-Stokes equations. The coolant air issuing from around the stagnation point as an array of three jets spreads over both the upper and the lower sides of the cylinder surface and about 40 ~ 60% cooling effectiveness
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A mean free path approach to the micro/nanochannel gas flows Adv. Aerodyn. Pub Date : 2020-05-07 Jianfei Xie
We investigate the gas flows near to solid surfaces in terms of the local spatial variation in the molecular mean free path (MFP). Molecular dynamics (MD) is the appropriate scientific tool for obtaining molecularly-accurate dynamic information in micro and nano-scale gas flows, and has been used to evaluate the molecular mean free path of gases. In the calibration procedure, the viscosity of a gas
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Fiber optic sensing technologies potentially applicable for hypersonic wind tunnel harsh environments Adv. Aerodyn. Pub Date : 2020-04-24 Huacheng Qiu; Fu Min; Yanguang Yang
Advanced sensing techniques are in big demand for applications in hypersonic wind tunnel harsh environments, such as aero(thermo)dynamics measurements, thermal protection of aircraft structures, air-breathing propulsion, light-weighted and high-strength materials, etc. In comparison with traditional electromechanical or electronic sensors, the fiber optic sensors have relatively high potential to work
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Unsteady shock front waviness in shock-buffet of transonic aircraft Adv. Aerodyn. Pub Date : 2020-04-23 Razvan Marian Apetrei; Vlad Ciobaca; Jose Luis Curiel-Sosa; Ning Qin
The unsteady transonic aerodynamics of a wing-body configuration is investigated by solving the Unsteady Reynolds-averaged Navier-Stokes equations closed with the full Reynolds Stress Model. This work presents the prediction of flow field characteristics during deep shock-buffet penetration of a transport aircraft-representative geometry. Mach number of 0.85, and Reynolds number of 5 million based
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Computational simulations of near-continuum gas flow using Navier-Stokes-Fourier equations with slip and jump conditions based on the modal discontinuous Galerkin method Adv. Aerodyn. Pub Date : 2020-04-21 T. Chourushi; A. Rahimi; S. Singh; R. S. Myong
Blunt-body configurations are the most common geometries adopted for non-lifting re-entry vehicles. Hypersonic re-entry vehicles experience different flow regimes during flight due to drastic changes in atmospheric density. The conventional Navier-Stokes-Fourier equations with no-slip and no-jump boundary conditions may not provide accurate information regarding the aerothermodynamic properties of
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DSMC modeling of rarefied ionization reactions and applications to hypervelocity spacecraft reentry flows Adv. Aerodyn. Pub Date : 2020-03-17 Ming Fang; Zhi-Hui Li; Zhong-Hua Li; Jie Liang; Yong-Hao Zhang
The DSMC modeling is developed to simulate three-dimensional (3D) rarefied ionization flows and numerically forecast the communication blackout around spacecraft during hypervelocity reentry. A new weighting factor scheme for rare species is introduced, whose key point is to modify the corresponding chemical reaction coefficients involving electrons, meanwhile reproduce the rare species in resultants
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On the calculation of the electron temperature flowfield in the DSMC studies of ionized re-entry flows Adv. Aerodyn. Pub Date : 2020-03-04 Alexander Shevyrin; Yevgeniy Bondar
Currently available procedures of electron temperature calculations in studying ionized flows around reentry spacecraft by the direct simulation Monte Carlo (DSMC) method are analyzed. It is shown that the heat conduction of electrons is not taken into account in these procedures. The contributions of various effects to the electron energy balance are calculated by an example of the RAM-C II capsule
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Aerodynamics and dynamic stability of micro-air-vehicle with four flapping wings in hovering flight Adv. Aerodyn. Pub Date : 2020-02-17 Cheng Cheng; Jianghao Wu; Yanlai Zhang; Han Li; Chao Zhou
Recently, a novel concept of flapping Micro-Air-Vehicles (FMAVs) with four wings has been proposed, which potentially utilizes the clap-and-fling effect for lift enhancement and agile maneuvers through an adjustment of wing kinematics. However, the application of the clap-and-fling effect in the four-winged FMAVs is underexplored and the dynamic stability is still unclear. In this paper, aerodynamics
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Recent investigations of shock wave effects and interactions Adv. Aerodyn. Pub Date : 2020-02-07 P. M. Ligrani; E. S. McNabb; H. Collopy; M. Anderson; S. M. Marko
Despite over fifty years of research on shock wave boundary layer effects and interactions, many related technical issues continue to be controversial and debated. The present survey provides an overview of the present state of knowledge on such effects and interactions, including discussions of: (i) general features of shock wave interactions, (ii) test section configurations for investigation of
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Discrete unified gas kinetic scheme for multiscale anisotropic radiative heat transfer Adv. Aerodyn. Pub Date : 2020-01-10 Xinliang Song; Chuang Zhang; Xiafeng Zhou; Zhaoli Guo
In this work, a discrete unified gas kinetic scheme (DUGKS) is developed for radiative transfer in anisotropic scattering media. The method is an extension of a previous one for isotropic radiation problems [1]. The present scheme is a finite-volume discretization of the anisotropic gray radiation equation, where the anisotropic scattering phase function is approximated by the Legendre polynomial expansion
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On the accuracy of macroscopic equations for linearized rarefied gas flows Adv. Aerodyn. Pub Date : 2020-01-08 Lei Wu; Xiao-Jun Gu
Many macroscopic equations are proposed to describe the rarefied gas dynamics beyond the Navier-Stokes level, either from the mesoscopic Boltzmann equation or some physical arguments, including (i) Burnett, Woods, super-Burnett, augmented Burnett equations derived from the Chapman-Enskog expansion of the Boltzmann equation, (ii) Grad 13, regularized 13/26 moment equations, rational extended thermodynamics
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Nonlinear L1 adaptive control of stagnation pressure in a cryogenic wind tunnel Adv. Aerodyn. Pub Date : 2020-01-02 Rusong Zhu; Mingwei Xie; Daxiong Liao; Gengsheng Tang; Wen Gai
Cryogenic wind tunnel is a sophisticated aerodynamics ground test facility, which operates in cryogenic temperature with injection of liquid nitrogen. The multi-variable, nonlinear and coupled dynamics existing between the temperature, pressure and Mach number in the tunnel, poses great challenges for the effective control of the tunnel. L1 adaptive control is a new control methodology developed in
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On the mesh resolution of industrial LES based on the DNS of flow over the T106C turbine Adv. Aerodyn. Pub Date : 2019-12-28 Mohammad Alhawwary; Z.J. Wang
A high-order Navier-Stokes solver based on the flux reconstruction (FR) or the correction procedure via reconstruction (CPR) formulation is employed to perform a direct numerical simulation (DNS) and large eddy simulations (LES) of a well-known benchmark problem – transitional flow over the low-pressure T106C turbine cascade. Hp-refinement studies are carried out to assess the resolution requirement
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Aerodynamic analysis of a generic wing featuring an elasto-flexible lifting surface Adv. Aerodyn. Pub Date : 2019-12-20 J. Piquee; I. López Canalejo; C. Breitsamter; R. Wüchner; K.-U. Bletzinger
A three-dimensional-membrane-type wing is investigated applying fluid-structure-interaction computations and complementary experiments. An analysis for three Reynolds numbers is conducted at various angles of attack. The computations are performed by means of the TAU-Code and the FEM Carat++ solver. Wind-tunnel tests are carried out for performance analysis and to estimate the accuracy of the computations
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From primary instabilities to secondary instabilities in Görtler vortex flows Adv. Aerodyn. Pub Date : 2019-10-29 Xi Chen; Jianqiang Chen; Xianxu Yuan; Guohua Tu; Yifeng Zhang
We have studied the transformation process from primary instabilities to secondary instabilities with direct numerical simulations and stability theories (Spatial Biglobal and plane-marching parabolized stability equations) in detail. First Mack mode and second Mack mode are shown to be able to evolve into the sinuous mode and the varicose mode of secondary instability, respectively. Although the characteristics
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Accuracy analysis of gradient reconstruction on isotropic unstructured meshes and its effects on inviscid flow simulation Adv. Aerodyn. Pub Date : 2019-09-17 Nianhua Wang; Ming Li; Rong Ma; Laiping Zhang
The accuracy of gradient reconstruction methods on unstructured meshes is analyzed both mathematically and numerically. Mathematical derivations reveal that, for gradient reconstruction based on the Green-Gauss theorem (the GG methods), if the summation of first-and-lower-order terms does not counterbalance in the discretized integral process, which rarely occurs, second-order accurate approximation
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The computation of the pitch damping stability derivatives of supersonic blunt cones using unsteady sensitivity equations Adv. Aerodyn. Pub Date : 2019-07-20 Chenxi Guo; Yu-xin Ren
The numerical methods for computing the stability derivatives of the aircraft by solving unsteady sensitivity equations which was proposed in our previous papers was extended to solve three-dimensional problems in this paper. Both the static and dynamic derivatives of the hypersonic blunt cone undergoing pitching oscillation around a fixed point were computed using the new methods. The predicted static
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A brief review on the convergence to steady state solutions of Euler equations with high-order WENO schemes Adv. Aerodyn. Pub Date : 2019-07-18 Shuhai Zhang; Jun Zhu; Chi-Wang Shu
Weighted essentially non-oscillatory (WENO) schemes are a class of high-order shock capturing schemes which have been designed and applied to solve many fluid dynamics problems to study the detailed flow structures and their evolutions. However, like many other high-order shock capturing schemes, WENO schemes also suffer from the problem that it can not easily converge to a steady state solution if
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On the vorticity behind 3-D detached bow shock wave Adv. Aerodyn. Pub Date : 2019-07-08 V. N. Golubkin; G. B. Sizykh
For the general case of a spatial isoenergetic flow of ideal gas, Helmholtz’s theorems are generalized and the speed with which vortex tubes move is found, keeping the intensity. It is shown that along the streamline without stagnation point, vorticity either is equal to zero everywhere, or it is non zero at all. The pattern of vortex lines behind the three-dimensional detached bow shock wave is specified
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Experimental and numerical investigation of controlled disturbances development from two sources in supersonic boundary layer Adv. Aerodyn. Pub Date : 2019-07-05 G. L. Kolosov; A. D. Kosinov; A. N. Semenov; A. A. Yatskikh
The paper presents the experimental results and the results of direct numerical simulation of the development and interaction of two wave trains from two point sources of controlled disturbances in a supersonic boundary layer on a flat plate with an incident flow Mach number of 2.5. Sources were located parallel to the leading edge of the model. For the introduction of controlled disturbances into
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Compact higher-order gas-kinetic schemes with spectral-like resolution for compressible flow simulations Adv. Aerodyn. Pub Date : 2019-06-06 Fengxiang Zhao; Xing Ji; Wei Shyy; Kun Xu
In this paper, a class of compact higher-order gas-kinetic schemes (GKS) with spectral-like resolution will be presented. Based on the high-order gas evolution model, both the flux function and conservative flow variables in GKS can be evaluated explicitly from the time-accurate gas distribution function at a cell interface. As a result, inside each control volume both the cell-averaged flow variables
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Particle-based hybrid and multiscale methods for nonequilibrium gas flows Adv. Aerodyn. Pub Date : 2019-05-30 Jun Zhang; Benzi John; Marcel Pfeiffer; Fei Fei; Dongsheng Wen
Over the past half century, a variety of computational fluid dynamics (CFD) methods and the direct simulation Monte Carlo (DSMC) method have been widely and successfully applied to the simulation of gas flows for the continuum and rarefied regime, respectively. However, they both encounter difficulties when dealing with multiscale gas flows in modern engineering problems, where the whole system is
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Theoretical fundamentals of airframe/propulsion integration for high-speed aircraft Adv. Aerodyn. Pub Date : 2019-05-28 A. A. Gubanov
Fundamental features of aerodynamic interference and integration of airframes and air-breathing jet engines for high-speed flight vehicles are studied within the framework of supersonic small perturbation theory. Both the influence of airframe components on air intakes performance and influence of intakes on vehicle external aerodynamics are under consideration. Analytical relations and specific examples
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RANS and hybrid LES/RANS simulations of flow over a square cylinder Adv. Aerodyn. Pub Date : 2019-05-02 Jianghua Ke
Unsteady RANS (URANS), hybrid LES/RANS and IDDES simulations were conducted to numerically investigate the velocity field around, and pressures distribution and forces over a square cylinder immersed in a uniform, steady oncoming flow with Reynolds number Re = 21,400. The vortex shedding responses in terms of Strouhal number, the pressure distribution, the velocity profile and the velocity fluctuations
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On hybrid temporal basis functions for stable numerical solution of time domain boundary integral equations Adv. Aerodyn. Pub Date : 2019-03-25 Fang Q. Hu
Problems in unsteady aerodynamics and aeroacoustics can sometimes be formulated as integral equations, such as the boundary integral equations. Numerical discretization of integral equations in the time domain often leads to so-called March-On-in-Time (MOT) schemes. In the literature, the temporal basis functions used in MOT schemes have been largely limited to low-order shifted Lagrange basis functions
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An implicit parallel UGKS solver for flows covering various regimes Adv. Aerodyn. Pub Date : 2019-03-13 Dingwu Jiang; Meiliang Mao; Jin Li; Xiaogang Deng
This paper presents an engineering-oriented UGKS solver package developed in China Aerodynamics Research and Development Center (CARDC). The solver is programmed in Fortran language and uses structured body-fitted mesh, aiming for predicting aerodynamic and aerothermodynamics characteristics in flows covering various regimes on complex three-dimensional configurations. The conservative discrete ordinate
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Modern problems of aircraft aerodynamics Adv. Aerodyn. Pub Date : 2019-03-07 Sergey L. Chernyshev; Sergey V. Lyapunov; Andrey V. Wolkov
The article represents the discussion of several separate directions of investigations, which are performed by TsAGI flight vehicles aerodynamics specialists at the time. There are some major trends of classical layout of route aircraft and also peculiarities of some prospective flight vehicles. Also there are some hypersonic vehicles aerodynamics questions examined along with problems of creation
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A theoretical study of serrated leading edges in aerofoil and vortical gust interaction noise Adv. Aerodyn. Pub Date : 2019-02-28 Xun Huang
Serrated leading edges are one of the most promising passive aerodynamic control methods for the reduction of aerofoil–turbulence interaction noise. To elucidate the possible physical mechanisms, the current paper studies the simplified set-up with aerofoil–vortical gust interaction and proposes an analytical model by incorporating Fourier transform into the Wiener–Hopf method. The proposed model suggests
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Gas-kinetic unified algorithm for computable modeling of Boltzmann equation and application to aerothermodynamics for falling disintegration of uncontrolled Tiangong-No.1 spacecraft Adv. Aerodyn. Pub Date : 2019-02-22 Zhi-Hui Li; Ao-Ping Peng; Qiang Ma; Lei-Ning Dang; Xiao-Wei Tang; Xue-Zhou Sun
How to solve the hypersonic aerothermodynamics around large-scale uncontrolled spacecraft during falling disintegrated process from outer space to earth, is the key to resolve the problems of the uncontrolled Tiangong-No.1 spacecraft reentry crash. To study aerodynamics of spacecraft reentry covering various flow regimes, a Gas-Kinetic Unified Algorithm (GKUA) has been presented by computable modeling
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Two-stage fourth order: temporal-spatial coupling in computational fluid dynamics (CFD) Adv. Aerodyn. Pub Date : 2019-02-21 Jiequan Li
With increasing engineering demands, there need high order accurate schemes embedded with precise physical information in order to capture delicate small scale structures and strong waves with correct “physics”. There are two families of high order methods: One is the method of line, relying on the Runge-Kutta (R-K) time-stepping. The building block is the Riemann solution labeled as the solution element
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Analysis of shock wave unsteadiness using space and time correlations applied to shadowgraph flow visualization data Adv. Aerodyn. Pub Date : 2019-02-03 S. Marko; P. M. Ligrani
Unsteady flow characteristics of a normal shock wave, a lambda foot, and a separated turbulent boundary layer are investigated within a unique test section with supersonic inlet flow. The supersonic wind tunnel facility, containing this test section, provides a Mach number of approximately 1.54 at the test section entrance. Digitized shadowgraph flow visualization data are employed to visualize shock
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Landmarks and new frontiers of computational fluid dynamics Adv. Aerodyn. Pub Date : 2019-01-31 Joseph J. S. Shang
A narrative of landmarks in computational fluid dynamics (CFD) is presented to highlight the cornerstone achievements. Illuminating accomplishments starting from the very beginning of the coherent development until the most recent progress will be elucidated over the span over more than six decades. Meanwhile, the cutting-edge scientific innovations will also be discussed for their lasting impacts
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Numerical investigation of an active TPS for a wing leading edge exposed to high temperature air behind a strong bow shock wave Adv. Aerodyn. Pub Date : 2019-01-30 Taku Ohwada; Tomonori Shimada; Takuma Kato
An array of subsonic counter-flow jets is studied as an active thermal protection system (TPS) for wing leading edges of hypersonic vehicles. The performance is numerically estimated in the model case of a circular cylinder on the basis of the 2D compressible Navier-Stokes equations. In contrast to a single subsonic jet, an array of jets is robust against variation of the angle of attack; high cooling
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