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Effects of trips on the oscillatory flow of an axisymmetric hypersonic inlet with downstream throttle

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Chinese Journal of Aeronautics 2018年第2期31卷 225-236页

作者： Wenzhi GAO Zhufei LI Jiming YANG yishan zeng School of Mechanical Engineering Hefei University of Technology Department of Modern Mechanics University of Science and Technology of China

Experimental investigations are conducted on an axisymmetric hypersonic inlet to evaluate the effects of trips on oscillatory flows. The model exit is throttled with a fixed block to generate oscillatory flows at a freestream Mach number of 6 in a conventional wind tunnel and a shock tunnel. Schlieren imaging and pressure measurements are adopted to record unsteady flow *** indicate that trips with a 1 mm thickness prominently suppress external separations, shorten oscillatory cycles, and modify pressure magnitudes. Trips can reduce the upstream movement ranges of separated shocks from nose regions to locations axially 142 mm downstream. The oscillatory cycles are shortened from 3.75 ms to 3.25 ms and from 4 ms to 3.13 ms in two *** cases generally exhibit higher pressure magnitudes than those of untripped cases, of which the increment is up to 21 times the freestream static pressure for the farthest downstream transducer in the shock tunnel. The effects of trips are related to the streamwise vortexes in wake flows, in which interactions between external separations modify the separated flow patterns and enhance the sustainment of the forebody boundary layers to backpressure. Flow processes causing increments of oscillatory frequencies and pressure magnitudes are analyzed, while the flow mechanisms dominating the processes still need to be clarified in the future.

关键词： Backpressure Flow separations Hypersonic inlets Inlet unstart Oscillatory flow Trips

Geology,Genetic Types and Metallogeny of Gold Deposits in the Eastern Tianshan,Xinjiang

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Acta Geologica Sinica(English Edition) 2000年第3期74卷 559-564页

作者： FENG Jianzhong zeng yishan FU Shuixing Peking University Beijing 100871 Beijing Institute of Geology for Mineral Resources AndingmenwaiBeijing 100012

As a typical Palaeozoic island arc system, the eastern Tianshan area, Xinjiang, is different from eastern China but similar to the Meso-Cenozoic island arc metallogenic provinces along the coast of the Pacific Ocean in metallogenic environment, geology and geochemistry. Three types of gold deposits, ductile shear zone-hosted gold deposits (Kanggur'), magmatic hydrothermal gold deposits (Jinwozi) and volcanic- or subvolcanic-hosted gold deposits (Xitan and Mazhuangshan), have been identified in this area. Regionally, gold deposits are structurally controlled by the Kanggur Tag ductile shear zone, Shaquanzi fault, Hongliuhe fault and Yamansu fault. Generally, gold mineralization occurs in the transition zones from volcanic rocks to sedimentary rocks. The horizon bearing well-developed jasper is an important indicator for gold mineralization. Each of the three types of gold deposits has its distinctive metallogenic background and geological-geochemical characteristics.

关键词： eastern Tianshan gold metallogeny genetic type geology geochemistry

Study on Composition of Inclusions in Minerals and Simulation Experiment on Hydrothermal Metasomatic Process of the Bayan Obo Iron Deposit

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Acta Geologica Sinica(English Edition) 1986年第4期60卷 43-55页

作者： zeng yishan, Wang Fengzhen, He Zongli, Liu Guoping, Wang Chengqiang and Hao Jicheng Department of Geology, Peking University, Beijing Department of Geology Peking University Beijing

On the basis of the mechanism of formation of mineral inclusions, it may be assumed that a certain relation exists between the compositions of fluid inclusions in various minerals formed at the same stage of hydrothermal activity. In order to study the genetic relationships between different minerals in the Bayan Obo iron deposit, the compositions(K;, Na;, Ca;, Mg;, F;, Cl;, CO;, ΣSO;and pH) of inclusions in fluorite（23）, hematite（13）, magnetite（3）, sodium pyroxene（2） and dolomite（5） from the main mine and the eastern mine were determined by using the vacuum decrepitation and leaching methods, and cluster analyses of the data on the compostions were made. The Q-mode cluster analysis indicates that some iron oxide minerals in the deposit are related to dolomite of sedimentary origin, while others are related to fluorite and sodium pyroxene--products of hydrothermal activity. The R-mode cluster analysis shows that the components of the leaching solution may be divided into two groups: one includes CO;, Mg;and H;（pH）, which are obviously associated with dolomite; the other comprises Na;, K;, Ca;, F;, Cl;and SO;, which may possibly represent the composition of hydrothermal *** reaction of the Na-F-Cl solution（pH 4.72） with hematite dolomite at 300℃ and 5 × 10;Pa and under alternately"static and dynamic" conditions produced large amounts of hematite and fluorite and small amounts of smectite and Na（Fe） silicates, and the hematite-fluorite assemblage accords with the actual geological conditions in the deposit. From a comparison between the compositions of"static" and"dynamic" solution samples, it may be known that the flow reaction facilitates the migration of Fe, F, Ca and other components as well as Na-metasomatism（Na and Si are fixed in a solid phase）.The study of the compositions of mineral inclusions and simulation experiments on hydrothermal metasomatism have provided new evidence for the hypothesis of metamorphosed-sedimentary and hydrothermal-remoulding

关键词： Study on Composition of Inclusions in Minerals and Simulation Experiment on Hydrothermal Metasomatic Process of the Bayan Obo Iron Deposit

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一种改进的无单元伽辽金方法

计算物理 2007年第1期24卷 35-41页

作者：曾亿山曾清红合肥工业大学机械与汽车工程学院安徽合肥230009 中国科学技术大学力学和机械工程系安徽合肥230027

使用单位分解积分,对传统的无单元伽辽金方法进行改进.有限覆盖和单位分解是单位分解积分的数学基础,对单位分解积分进行了严格证明,并指出使用Shepard函数作为单位分解函数是一个很好的选择.数值实例表明,使用单位分解积分进行数值求... 详细信息

使用单位分解积分,对传统的无单元伽辽金方法进行改进.有限覆盖和单位分解是单位分解积分的数学基础,对单位分解积分进行了严格证明,并指出使用Shepard函数作为单位分解函数是一个很好的选择.数值实例表明,使用单位分解积分进行数值求积的无单元伽辽金方法是一种真正的无网格方法,与经典的背景网格积分相比具有更高的精度.

关键词：无网格方法无单元伽辽金方法数值积分有限覆盖单位分解单位分解积分

100MPa压力下温度和水对干酪根结构状态影响的实验研究

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岩石学报 2005年第1期21卷 245-250页

作者：曾贻善吴朝东北京大学地质系北京100871

为了实验验证变质沉积物中的碳质物拉曼光谱地质温度计的可用性,利用冷封口式高温高压水热系统将焊封金管内的干酪根于100MPa压力和温度(250-700℃)、有水和无水条件下处理24小时,激光拉曼探针(LRM)分析表明,实验所得碳质物的一级和二... 详细信息

为了实验验证变质沉积物中的碳质物拉曼光谱地质温度计的可用性,利用冷封口式高温高压水热系统将焊封金管内的干酪根于100MPa压力和温度(250-700℃)、有水和无水条件下处理24小时,激光拉曼探针(LRM)分析表明,实验所得碳质物的一级和二级拉曼谱特征(拉曼峰的存在、峰的位置、宽度、高度和面积)随温度系统地变化,所得碳质物的D/O比值随温度升高而减小,但在D/O比-温度关系图上-500℃处有一拐点(极小)。实验条件下处理的干酪根的显微富利叶变换红外谱(micro-FTIR)分析表明,脂族C-H和芳族C-H吸收峰的相对强度在500℃左右急剧变化以及在700℃的实验产物中仍存在含氢的功能团。高温高压条件下,水的存在不利于碳质物的石墨化(有序化)。

关键词：干酪根结构状态拉曼谱学红外谱学高温高压实验

DETERMINATION OF SOLUBILITY OF Fe2O3 IN DILUTE AQUEOUS SOLUTIONS AT 300℃ AND 10 MPa——APPENDING A DISCUSSION ABOUT THE TRANSPORTING FORM OF IRON IN HYDROTHERMAL SOLUTIONS

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Science in China,Ser.B 1986年第11期29卷 1221-1232页

作者：曾贻善艾瑞英陈月团 Department of Geology Peking University

The solubility of Fe2O3 in dilute KOH and HClO4 aqueous solutions was determined at 300℃ and 10 MPa. The analysis of the solubility data indicated that in neutral and alkaline hydrothermal solutions iron mostly existed as Fe（OH）30 and Fe（OH）4-, and it was calculated that △GFe（OH）300=-561.9±3.3kJ/mol, and △GFe（OH）400=-662.7±5.0 kJ/mol at 300℃. According to the analysis on the previous experimental studies about the transporting form of iron, the existing form of iron in hydrothermal solutions is discussed in this paper.

关键词： Fe DETERMINATION OF SOLUBILITY OF Fe2O3 IN DILUTE AQUEOUS SOLUTIONS AT 300 APPENDING A DISCUSSION ABOUT THE TRANSPORTING FORM OF IRON IN HYDROTHERMAL SOLUTIONS AT

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矾山杂岩体中磷灰石组成特征及其地质意义

岩石矿物学杂志 2001年第2期20卷 156-161页

作者：蔡俊军吴淑华曾凡刚曾贻善中国地质科学院地质研究所北京100037 孝感第一高级中学湖北孝感432100 中央民族大学生物化学系北京100081 北京大学地质学系北京100871

用电子探针和红外光谱测定矾山岩系小尺度第六韵律岩层中磷灰石的元素含量和阴离子组成 ,结果表明该单元中磷灰石的主要元素含量呈微小幅度的起伏性变化 ;由该韵律单元的底部到顶部分 ,磷灰石A10 (ZO4 ) 6 X2 结构中的X位置 ,起初为F- ... 详细信息

用电子探针和红外光谱测定矾山岩系小尺度第六韵律岩层中磷灰石的元素含量和阴离子组成 ,结果表明该单元中磷灰石的主要元素含量呈微小幅度的起伏性变化 ;由该韵律单元的底部到顶部分 ,磷灰石A10 (ZO4 ) 6 X2 结构中的X位置 ,起初为F- 、Cl- 交替占据 ,然后主要为Cl- 占据 ,直至完全为Cl- 占据 ,成为氯磷灰石。初步推断。

关键词：层状杂岩体磁铁磷灰石矿床电子探针红外光谱沉积层位

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单裂隙流-固耦合渗流的试验研究

实验力学 2005年第1期20卷 10-16页

作者：曾亿山卢德唐曾清红董虎合肥工业大学机械与汽车工程学院合肥230009 中国科学技术大学力学与机械工程系合肥230026

通过对较大尺寸的单裂隙岩体试块进行不同侧面加载的渗流试验,在实验室里开展了单裂隙流固耦合渗流研究,模拟核废料贮藏库的围岩自由面的最危险部位的渗流量应力耦合状态。分析了裂隙岩体渗流与应力的耦合机理,获得了几种典型情况下... 详细信息

通过对较大尺寸的单裂隙岩体试块进行不同侧面加载的渗流试验,在实验室里开展了单裂隙流固耦合渗流研究,模拟核废料贮藏库的围岩自由面的最危险部位的渗流量应力耦合状态。分析了裂隙岩体渗流与应力的耦合机理,获得了几种典型情况下的试验数据,并拟合出不同应力条件下单裂隙岩体渗流量与应力间数学经验公式。从而说明并非任一方向的应力增加都能使渗流量减小,而是裂隙岩体的渗流量随着双向压应力的增加而减少,随着平行于裂隙面方向的单向压应力的增加而增加。缝隙开度虽然随着法向应力的增加而逐渐减小,但最终不可能完全闭合,所以,此时流量不可能为零。同时,在试验过程中还通过闭环控制来实现被加载面的均匀受力,这为大尺寸岩体试验提供了一种很好的加载方法。

关键词：耦合渗流单裂隙试验研究裂隙岩体渗流量渗流试验应力耦合耦合机理岩体渗流试验数据经验公式应力条件法向应力闭环控制试验过程加载方法大尺寸压应力实验室自由面贮藏库核废料裂隙面减小闭合

前体涡发生器对轴对称高超声速进气道激波振荡流动的影响实验

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力学学报 2018年第2期50卷 209-220页

作者：高文智李祝飞曾亿山杨基明合肥工业大学机械工程学院合肥230009 中国科学技术大学近代力学系合肥230027

激波振荡是高超声速进气道不起动过程中常见的流动现象,会显著降低进气道气流捕获与压缩效率、产生剧烈的非定常气动力载荷而危害飞行器安全.从激波振荡的控制出发,实验研究了前体转捩带位置的涡发生器对轴对称高超声速进气道激波振荡... 详细信息

激波振荡是高超声速进气道不起动过程中常见的流动现象,会显著降低进气道气流捕获与压缩效率、产生剧烈的非定常气动力载荷而危害飞行器安全.从激波振荡的控制出发,实验研究了前体转捩带位置的涡发生器对轴对称高超声速进气道激波振荡流动的影响.分别在起动和激波振荡两种进气道流态下,选择无、0.5 mm与1 mm高度涡发生器工况进行对比研究.并采用高速纹影与壁面动态测压同步记录非定常流动特征.结果表明,1 mm高度内的涡发生器对起动状态的进气道主流流场结构、壁面压强分布影响不显著.但对于激波振荡流动,涡发生器会明显缩小外压缩面分离区运动范围,缩短振荡周期,提升振荡周期内壁面压强的时均值.涡发生器的影响程度随其高度的增大而增强,其中振荡周期从无涡发生器的4 ms缩短到1 mm高度涡发生器的3.13 ms.此外,0.5 mm高度涡发生器会使得进气道内部测点的压强振荡幅值整体下降,相比无涡发生器工况的下降幅度可达23%.流场结构与壁面压强信号的分析表明,涡流发生器主要通过其产生的流向涡影响激波振荡流动,包含流向涡对下游边界层的扰动以及流向涡与分离区的相互干扰.

关键词：激波振荡高超声速进气道涡发生器非定常分离流激波风洞