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对“二阶迎风TVD数值格式在非平衡高超声速钝体绕流中的应用”一文的讨论
胡光初
力学学报 , 1998,
Abstract: 为了方便讨论,将我们于1994年3月在《力学学报》第2期上发表的“M阶迎风TVD数值格式在非平衡高超声速钝体绕流中的应用”一文列为本文参考文献[6].IYee.Harten二阶迎风TVD格式粘性流场计算结果的可靠性问题文[6]和本文所提到的Yee~HartenTVD格式的二阶精度是指一维标量偏微分方程离散的差分格式的计算精度(此处引用文献[1]原文作者的提法Second-OrderUnwindTVDSCheme)根据Yee;H.C.(见文献[1])和国内学者(见文献[7~10,12])研究表明Yee-HartenTVD格式直接推广到多维情况下,计算结果分辨率高并具有足…
圆柱绕流远场旋涡结构的数值研究  [PDF]
吴文权,居江宁
工程热物理学报 , 2001,
Abstract: 基于离散涡方法求解非定常、不稳定流场。数值模拟了高雷诺数下圆柱绕流旋涡结构的发展。从流谱图、等涡量线图和涡谱图可以清晰地看出从近场初生的卡门涡街,过渡到远场的二次涡街的过程。计算结果发现:远场离散涡有形成二个涡的涡对及三个涡的涡对结构的趋势。计算结果说明了流体运动中涡对结构的本质:远场形成的二次涡对及卡门涡街是由于流动本身的动力不稳定而引起的,从而增加对远场尾迹流及涡对结构的理解。
二阶迎风TVD数值格式在非平衡高超声速钝体绕流中的应用  [PDF]
胡光初,乐嘉陵,曹文祥
力学学报 , 1994, DOI: 10.6052/0459-1879-1994-2-1995-531
Abstract: 将H.C.Yee所发展的一种二阶迎风TVD格式运用于半球的高超声速化学非平衡黏性绕流的数值计算,详细介绍了流体力学方程组和化学组元守恒方程组全耦合求解的过程,以前这一研究领域中仅仅运用一阶格式及松散耦合的方法。化学松弛气体考虑了七组元(O,O_2,NO,N,NO ̄(+),N_2,e ̄(-))和主要的七反应,在驻点线上的计算结果与前人结果比较表明,本文有较大改进。
DISCUSSION ON "APPLICATIONS OF A SECOND-ORDERUPWIND TVD SCHEME TO NONEQUILIBRIUM HYPERSONICFLOWS AROUND BLUNT-BODY
对“二阶迎风TVD数值格式在非平衡高超声速钝体绕流中的应用”一文的意见

高树椿,黎作武
力学学报 , 1998,
Abstract: 看了《力学学报》第26卷第2期(1994年3月)发表的胡光初1]等同志的论文“M阶迎风TVD数值格式在非平衡高超声速钝体绕流中的应用”一文以后,关于计算精度和结果可靠性问题。我们提出以下不同的意见.在文问中多处讲到关于格式的精度问题,并一再强调以前这项研究工作别人用的
APPLICATIONS OF A SECOND-ORDER UPWIND TVD SCHEME TO NONEQUILIBRIUM HYPERSONIC FLOWS AROUND BLUNT-BODY
二阶迎风TVD数值格式在非平衡高超声速钝体绕流中的应用

Hu Guangchu,Le Jialing,Cao Wenxiang,
胡光初
,乐嘉陵,曹文祥

力学学报 , 1994,
Abstract: An explicit second-order upwind TVD scheme by H.C.Yee is first suc-cessfully extended to solve the viscous,diffussive,nonequilibrium,ionizing,hypersonic flowfields over a hemi-sphere.The governing gas-dynamic and species-continuity equations forlaminar flow are presented.The gas-dynamics/species continuity equations fully couplingprocedure is described in detail.Before this only the firstorder scheme and loosely coupledmethod was successfully used in this research field.The gais model for chemically relaxin...
对“二阶迎风TVD数值格式在非平衡高超声速钝体绕流中的运用”一文的讨论
胡光初
力学学报 , 1998,
Abstract: 对“二阶迎风TVD数值格式在非平衡高超声速钝体绕流中的运用”一文的讨论胡光初(中国空气动力研究与发展中心,四川绵阳621000)19961111收到.为了方便讨论,将我们于1994年3月在《力学学报》第2期上发表的“二阶迎风TVD数值格式在非平衡...
对“二阶迎风TVD数值格式在非平衡高超声速钝体绕流中的运用”一文的讨论  [PDF]
胡光初
力学学报 , 1998, DOI: 10.6052/0459-1879-1998-4-1995-156
Abstract: 对“二阶迎风TVD数值格式在非平衡高超声速钝体绕流中的运用”一文的讨论胡光初(中国空气动力研究与发展中心,四川绵阳621000)19961111收到.为了方便讨论,将我们于1994年3月在《力学学报》第2期上发表的“二阶迎风TVD数值格式在非平衡...
TVD Fields and Isentropic Gas Flow  [PDF]
Geng Chen,Helge Kristian Jenssen
Mathematics , 2012,
Abstract: Little is known about global existence of large-variation solutions to Cauchy problems for systems of conservation laws in one space dimension. Besides results for $L^\infty$ data via compensated compactness, the existence of global BV solutions for arbitrary BV data remains an outstanding open problem. In particular, it is not known if isentropic gas dynamics admits an a priori variation bound which applies to all BV data. In a few cases such results are available: scalar equations, Temple class systems, $2\times 2$-systems satisfying Bakhvalov's condition, and, in particular, isothermal gas dynamics. In each of these cases the equations admit a TVD (Total Variation Diminishing) field: a scalar function defined on state space whose spatial variation along entropic solutions does not increase in time. In this paper we consider strictly hyperbolic $2\times 2$-systems and derive a representation result for scalar fields that are TVD across all pairwise wave interactions, when the latter are resolved as in the Glimm scheme. We then use this to show that isentropic gas dynamics with a $\gamma$-law pressure function does not admit any nontrivial TVD field of this type.
亚临界雷诺数圆柱绕流远场气动噪声实验研究
Far-field aeroacoustic experimental study of flow around a circular cylinder at subcritical Reynolds number
 [PDF]

李玲,刘沛清,邢宇,郭昊,田云
- , 2016, DOI: 10.13700/j.bh.1001-5965.2015.0364
Abstract: 摘要 针对亚临界雷诺数下圆柱绕流的气动噪声问题,在北京航空航天大学D5气动声学风洞中进行了圆柱绕流远场气动噪声的实验研究。在D5气动声学风洞实验段不同来流条件下,测量消声室中距离圆柱不同位置的自由场传声器的远场声压信号,经过快速傅里叶变换(FFT)获得亚临界雷诺数下圆柱绕流气动噪声随来流速度、接收点距离的变化规律。实验结果表明:圆柱绕流的远场气动噪声在垂直气流方向最大,随着偏离垂直方向角度的增大噪声逐渐减小,属于典型的偶极子噪声源辐射特性;远场气动噪声近似与来流速度的6次方成正比,与接收点到圆柱中心距离的2次方成反比,这说明偶极子类型的噪声源是圆柱绕流的主要噪声源。
Abstract:To study the aeroacoustics of the flow around a circular cylinder at subcritical Reynolds number, the experimental investigation of far-field aerodynamic noise generated from flow past a circular cylinder was carried out in D5 aeroacoustic wind tunnel at Beihang University. Under variable flow conditions in the D5 test section, the signal of the sound pressure obtained from the free-field microphones at different positions in the anechoic chamber was measured. The dependence of far-field noise on free stream velocity and receiver position was acquired with the fast Fourier transform(FFT). With the qualitative and quantitative analysis of the aeroacoustic characteristics, the experimental results validate that the noise emitted from the circular cylinder is the largest in the direction vertical to the flow and decreases with the angle increasing, belonging to the characteristics of the sound radiated from a dipole sound source. The far-field aerodynamic noise generated from the cylinder is proportional to the sixth power of flow speed and inversely proportional to the twice power of the distance between the receiver and the center of the circular cylinder, confirming the domination of the dipolar noise source.
新型三阶TVD限制器性能分析
Performance analysis of a new-type third-order TVD limiter
 [PDF]

赵雅甜,阎超,孙迪,屈峰
- , 2017, DOI: 10.13700/j.bh.1001-5965.2016.0266
Abstract: 摘要 在计算流体力学(CFD)方法中,限制技术是影响计算精度和计算稳定性的重要因素,目前应用较广的经典二阶总变差衰减(TVD)限制器虽能较好地满足计算要求,但性能差异大且分辨率和耗散的性能间并未得到良好权衡。对一种新型的三阶TVD插值限制器(T-3限制器)进行了研究并将其与3种经典限制器进行对比。首先通过一维黎曼问题,得出T-3限制器兼顾较高间断分辨率和良好稳定性的特点;接着通过高超声速双锥绕流和X-33外形飞行器的数值实验,得到T-3限制器具有刻画复杂流动的能力以及较优的气动热计算性能。
Abstract:For numerical scheme in computational fluid dynamics (CFD), limiter technology is an important factor affecting computational accuracy and stability. Although the present classical second-order total variation diminishing (TVD) limiters with a wide application can well satisfy the computing requirements, its performance not only largely differs but also cannot be properly weighted between resolution and dissipation. Therefore, a new third-order TVD interpolation limiter (T-3 limiter) has been studied and compared with three classical limiters. First, through one-dimensional Riemann problem, it has been found that T-3 limiter is simultaneously characterized by both high intermittent resolution and excellent stability; then, by numerical simulation of hypersonic flow over a double-cone body and X-33 configuration, it has been found that T-3 limiter boasts the capability of portraying complex flow and good aerothermodynamic calculation performance.
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