The Fourth International Symposium on Refined Flow Modelling and TurbulenceMeasurements organized by International Association for Hydraulic Research(IAHR),and co-sponsored by a group of Chinese Institutes headed by W...The Fourth International Symposium on Refined Flow Modelling and TurbulenceMeasurements organized by International Association for Hydraulic Research(IAHR),and co-sponsored by a group of Chinese Institutes headed by Wuhan University ofHydraulic & Eiectric Engineering and Chinese Institute of Water Conservancy andHydroelectric Power Research is to be held on September 20-23,1990 at Wuhan City,People’s Republic of China.The Symposium is intended for presentation discussion and exchange of viewsbetween international colleagues on a wide scope of frontier problems regardingrefined flow modelling and turbulence measurements.The main topics are:展开更多
Interferometric Rayleigh scattering diagnostic technique for the time-resolved measurement of flow velocity is studied. Theoretically, this systematic velocity-measured accuracy can reach up to 1.23 m/s. Measurement a...Interferometric Rayleigh scattering diagnostic technique for the time-resolved measurement of flow velocity is studied. Theoretically, this systematic velocity-measured accuracy can reach up to 1.23 m/s. Measurement accuracy is then evaluated by comparing with hot wire anemometry results. Moreover, the distributions of velocity and turbulence intensity in a supersonic free jet from a Laval nozzle with a Mach number of 1.8 are also obtained quantitatively. The sampling rate in this measurement is determined to be approximately 10 k Hz.展开更多
On the basis of the fact that physical world possesses hierarchical structure and the concepts of nonstandard mathematics, a new description of turbulence was presented. Fundamental equations of turbulent flows were a...On the basis of the fact that physical world possesses hierarchical structure and the concepts of nonstandard mathematics, a new description of turbulence was presented. Fundamental equations of turbulent flows were also given. It is natural in this nonstandard picture of turbulence that the closure methods are obtained and seem to be precise.展开更多
The spatial growth of turbulent wind waves is investigated theoretically and experimentally. Introduction of wave induced turbulent Reynolds stress, in particu- lar at the average interface, makes great improvement in...The spatial growth of turbulent wind waves is investigated theoretically and experimentally. Introduction of wave induced turbulent Reynolds stress, in particu- lar at the average interface, makes great improvement in the prediction of wind wave properties.展开更多
The main objective of the present experimental study is to analyze the turbulent structure in humid airnon-premixed flame, and determine the effect of humidity on the flow field and the flame stability limit in turbul...The main objective of the present experimental study is to analyze the turbulent structure in humid airnon-premixed flame, and determine the effect of humidity on the flow field and the flame stability limit in turbulentnon-premixed flame. Particle Image Velocimetry (PIV) is used to capture the instantaneous appearance ofvortex structures and obtain the quantitative velocity field. The distributions of Reynolds shear stress, mean androot-mean squared fluctuating (rms) velocities are examined to get insight into the effect of fuel-to-air velocity ratioon velocity flow field. The results show that with steam addition, the air-driven vortex in the bluff-body wakeis thinner; the biggest peaks of rms velocity and Reynolds shear stress are lower; the distance between the peaksof rms velocity on the sides of centerline reduces. Besides these, the flame stability is affected. Both central fuelpenetration limit and partially quenching limit reduce with steam addition.展开更多
文摘The Fourth International Symposium on Refined Flow Modelling and TurbulenceMeasurements organized by International Association for Hydraulic Research(IAHR),and co-sponsored by a group of Chinese Institutes headed by Wuhan University ofHydraulic & Eiectric Engineering and Chinese Institute of Water Conservancy andHydroelectric Power Research is to be held on September 20-23,1990 at Wuhan City,People’s Republic of China.The Symposium is intended for presentation discussion and exchange of viewsbetween international colleagues on a wide scope of frontier problems regardingrefined flow modelling and turbulence measurements.The main topics are:
基金Project supported by the National Natural Science Foundation of China(Grant No.11272337)
文摘Interferometric Rayleigh scattering diagnostic technique for the time-resolved measurement of flow velocity is studied. Theoretically, this systematic velocity-measured accuracy can reach up to 1.23 m/s. Measurement accuracy is then evaluated by comparing with hot wire anemometry results. Moreover, the distributions of velocity and turbulence intensity in a supersonic free jet from a Laval nozzle with a Mach number of 1.8 are also obtained quantitatively. The sampling rate in this measurement is determined to be approximately 10 k Hz.
文摘On the basis of the fact that physical world possesses hierarchical structure and the concepts of nonstandard mathematics, a new description of turbulence was presented. Fundamental equations of turbulent flows were also given. It is natural in this nonstandard picture of turbulence that the closure methods are obtained and seem to be precise.
文摘The spatial growth of turbulent wind waves is investigated theoretically and experimentally. Introduction of wave induced turbulent Reynolds stress, in particu- lar at the average interface, makes great improvement in the prediction of wind wave properties.
基金supported by a Grant-in-Aid for Scientific Research through research grant number 2007CB210102 from State Key Fundamental Researeh Program of China.
文摘The main objective of the present experimental study is to analyze the turbulent structure in humid airnon-premixed flame, and determine the effect of humidity on the flow field and the flame stability limit in turbulentnon-premixed flame. Particle Image Velocimetry (PIV) is used to capture the instantaneous appearance ofvortex structures and obtain the quantitative velocity field. The distributions of Reynolds shear stress, mean androot-mean squared fluctuating (rms) velocities are examined to get insight into the effect of fuel-to-air velocity ratioon velocity flow field. The results show that with steam addition, the air-driven vortex in the bluff-body wakeis thinner; the biggest peaks of rms velocity and Reynolds shear stress are lower; the distance between the peaksof rms velocity on the sides of centerline reduces. Besides these, the flame stability is affected. Both central fuelpenetration limit and partially quenching limit reduce with steam addition.
