您的位置: 专家智库 > >

国家自然科学基金(50876053)

作品数:7 被引量:9H指数:2
相关作者:张会强卢浩王兵王希麟更多>>
相关机构:清华大学更多>>
发文基金:国家自然科学基金更多>>
相关领域:理学更多>>

文献类型

  • 7篇中文期刊文章

领域

  • 7篇理学

主题

  • 4篇湍流
  • 4篇壁湍流
  • 4篇粗糙元
  • 3篇拟序
  • 3篇拟序结构
  • 2篇COHERE...
  • 1篇湍流度
  • 1篇湍流拟序结构
  • 1篇流速仪
  • 1篇近壁湍流
  • 1篇壁面
  • 1篇OVER
  • 1篇PARTIC...
  • 1篇THREE-...
  • 1篇TURBUL...
  • 1篇TURBUL...
  • 1篇TURBUL...
  • 1篇ADV
  • 1篇CLUSTE...
  • 1篇LARGE_...

机构

  • 4篇清华大学

作者

  • 4篇王希麟
  • 4篇王兵
  • 4篇卢浩
  • 4篇张会强

传媒

  • 2篇工程热物理学...
  • 1篇清华大学学报...
  • 1篇Chines...
  • 1篇Acta M...
  • 1篇实验流体力学
  • 1篇Scienc...

年份

  • 1篇2017
  • 1篇2013
  • 1篇2012
  • 1篇2011
  • 2篇2010
  • 1篇2009
7 条 记 录,以下是 1-7
排序方式:
展向不同间距壁面粗糙元对近壁湍流拟序结构的影响被引量:4
2010年
采用氢气泡流动显示技术,研究了壁面不同展向间距粗糙元对近壁湍流拟序结构的影响。实验中粗糙元布置在氢泡丝前,其间距按如下两种排列设置:粗糙元直径的0、1和3倍,等间距1、2和4cm;每种情况粗糙元直径均为2.3、4和6mm。基于平均流速和水力直径的流动雷诺数从14000到48000变化。实验观测了光滑壁面和粗糙元壁面的近壁湍流拟序结构条带特征。发现:对于两种不同排列,相同雷诺数和相同粗糙元间距条件下条带有量纲间距均随着粗糙元直径增大而减小,条带有量纲高度均随粗糙元直径的增大而增大;相同雷诺数和相同直径粗糙元条件下条带有量纲间距均随着展向间距增大而增大,条带有量纲高度均随展向间距的增大而减小。粗糙元壁面湍流条带有量纲间距均比光滑壁面小,条带有量纲高度均比光滑壁面大。研究结果对近壁湍流的流动控制具有重要指导意义。
卢浩王兵张会强王希麟
关键词:壁湍流拟序结构粗糙元
展向和流向间距不同的粗糙元壁湍流ADV实验研究
2012年
为了揭示粗糙元对壁湍流的影响,采用声学Doppler流速仪(ADV)对布有展向或流向圆柱形粗糙元的壁湍流进行了实验测量。研究了不同Reynolds数下不同间距粗糙元对壁湍流流向平均速度和湍流度的影响。结果表明:在同一Reynolds数下,粗糙元展向间距为7倍直径时的壁湍流流向平均速度最小,湍流度最大。粗糙元流向布置的壁湍流流向平均速度随粗糙元间距的减小而减小,湍流度随粗糙元间距的减小而增大。相比流向粗糙元,展向粗糙元对湍流流动特性影响更大。研究结果对壁湍流流动控制和强化换热的工程应用具有指导意义。
卢浩张会强王兵王希麟
关键词:壁湍流湍流度粗糙元
Three-dimensional turbulent flow over cube-obstacles
2017年
In order to investigate the influence of surface roughness on turbulent flow and examine the wall-similarity hypothesis of Townsend, three-dimensional numerical study of turbulent channel flow over smooth and cube-rough walls with different roughness height has been carried out by using large eddy simulation(LES) coupled with immersed boundary method(IBM). The effects of surface roughness array on mean and fluctuating velocity profiles, Reynolds shear stress, and typical coherent structures such as quasi-streamwise vortices(QSV) in turbulent channel flow are obtained. The significant influences on turbulent fluctuations and structures are observed in roughness sub-layer(five times of roughness height).However, no dramatic modification of the log-law of the mean flow velocity and turbulence fluctuations can be found by surface cube roughness in the outer layer. Therefore, the results support the wall-similarity hypothesis. Moreover, the von Karman constant decreases with the increase of roughness height in the present simulation results. Besides, the larger size of QSV and more intense ejections are induced by the roughness elements, which is crucial for heat and mass transfer enhancement.
Hao LuWen-Jun ZhaoHui-Qiang ZhangBing WangXi-Lin Wang
不同排列粗糙元对湍流拟序结构的影响被引量:1
2011年
采用氢气泡流动显示技术,研究了壁面不同排列粗糙元对近壁湍流拟序结构的影响。实验中基于平均速度和水力直径的雷诺数分别为14300、31200、48000。氢泡丝上游布置的离散粗糙元直径为2.3、4和6mm,得到了光滑壁面和5种不同排列方式的离散粗糙元壁面湍流条带和湍流斑块特征。结果发现:相同雷诺数和相同排列方式下条带间距随着粗糙元直径增大而减小,条带或湍流斑块高度随粗糙元直径的增大而增大。对于不同粗糙元排列方式,当展向间距为0、流向间距为粗糙元直径4倍时,条带消失,出现大量混乱的湍流斑块,且此时湍流斑块高度最大,表明此种排列方式对壁湍流拟序结构影响最大。布有粗糙元时条带间距均比光滑壁面小,条带或湍流斑块高度均比光滑壁面大。该研究对于壁湍流控制的工程应用具有指导意义。
卢浩王兵张会强王希麟
关键词:壁湍流拟序结构粗糙元
Analysis of solid particle clusters in coherent structures of turbulent channel flow被引量:3
2013年
A particle-laden turbulent channel flow is investigated to study particle clusters in large-scale turbulent coherent structures. The fluid phase is calculated by large eddy simulation and particles are tracked using Lagrangian trajectory method. The flow Reynolds number is 180 based on the friction velocity and half-width of the channel. The particle is lycopodium with St=0.93 which may well follow the fluid phase. The mean and fluctuating velocities of both two phases are obtained, which are in good agreement with previous data. The strongest accumulations of particles in low-speed streak structures are observed at y~=l 1.3. Moreover, once particles are captured in low-speed streaks, most of them will reside there for a long period. Particles clustered in low-speed streaks obtain smaller instantaneous wall-normal and spanwise velocities than those out of there, which induce a larger particle flux into low-speed streaks than that out of there. The study is important for understanding particle dispersion mechanisms in gas-particle turbulent channel flows.
LU HaoWANG BingZHANG HuiQiangQIN JianXiuWANG XiLin
Particle modulations to turbulence in two-phase round jets被引量:1
2009年
The particle modulations to turbulence in round jets were experimentally studied by means of two-phase velocity measurements with Phase Doppler Anemometer (PDA). Laden with very large particles, no significant attenuations of turbulence intensities were measured in the farfields, due to small two-phase slip velocities and particle Reynolds number. The gas-phase turbulence is enhanced by particles in the near-fields, but it is significantly attenuated by the small particles in the far-fields. The smaller particles have a more profound effect on the attenuation of turbulence intensities. The enhancements or attenuations of turbulence intensities in the far-fields depends on the energy production, transport and dissipation mechanisms between the two phases, which are determined by the particle prop- erties and two-phase velocity slips. The non-dimensional parameter CTI is introduced to represent the change of turbulence intensity.
Bing Wang Huiqiang Zhang Yi Liu Xiaofen Yan Xilin Wang School of Aerospace, Tsinghua University, 100084 Beijing, China
不同粒径粗糙元对壁面湍流拟序结构的影响被引量:2
2010年
采用氢气泡流动显示技术,研究了不同粒径粗糙元对壁湍流拟序结构的影响。实验中粗糙元布置在氢泡丝前,均匀排成一排,基于平均速度和水力直径的雷诺数从14300到48000变化,离散粗糙元直径分别为0.9、1.6、2.3、4、5和6mm,粗糙元间距为2 cm。实验发现:光滑壁面和粗糙元壁面近壁湍流条带数量和条带高度都随雷诺数增大而增加。相同雷诺数下,粗糙元壁面流动产生的条带数量和条带高度随粗糙元粒径增大而增加。粗糙元壁面湍流条带数量和条带高度均比光滑壁面大。该研究对壁湍流的流动控制工程应用具有参考价值。
卢浩王兵张会强王希麟
关键词:壁湍流拟序结构粗糙元
共1页<1>
聚类工具0