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HYDRAULIC CHARACTERISTICS OF PLUG ENERGY DISSIPATER IN FLOOD DISCHARGE TUNNEL

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Journal of Hydrodynamics 2009年第6期21卷 799-806页

作者： TIAN Zhong XU Wei-Lin WANG Wei liu shan-jun State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065 China

The hydraulic characteristics of three types of plugs, namely, the single plug, the stepped plug and the gradually contracted plug were studied by means of experimental and numerical simulations. Main research findings are as follows. For the single plug, the pressure recovery lengths inside and after the plug range from 0.63-1.05 times and 2.02-2.84 times of the tunnel diameter, respectively. For the stepped plug, the lengths are 0.24-0.32 times and 1.62-2.84 times of the tunnel diameter, respectively. The best ratio of the inlet diameter to the outlet diameter of the gradually contracted plug can be expressed by a linear function. The relationship between the head loss coefficient and the area contraction ratio is obtained. The incipient cavitation numbers of different plugs are experimentally and numerically determined, and the incipient cavitation numbers are expressed by a formula. Model experiment with scale of 1：50 was carried out on a pressure tunnel with three-stage gradually contracted plugs. The results show that this type of energy dissipater is suitable for spill tunnels of high head （nearly 200 m） and large flow rate （nearly 2500 m^3/s）.

关键词： plug incipient cavitation number energy dissipater CFD

NUMERICAL SIMULATION OF 3-D FLOW FIELD IN ARCIFORM PLUNGE POOL

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Journal of Hydrodynamics 2002年第3期14卷 106-110页

作者： Xu, Wei-Lin liu, shan-jun Wang, Wei Qu, Jing-Xue Diao, Ming-jun Hydraulics Lab. of High Speed Flows Sichuan Univ. Chengdu 610065 China

The 3-D complex turbulent flow fields in a plunge pool with arciform bottom are simulated by using the k-Ε model in body-fitted coordinates. The calculated results reveal the flow characteristics in the arciform plunge pool under the different flood discharge conditions, which can not be easily obtained in the physical model test because the measurement of the complex velocity is very difficult. The calculated flow fields are helpful to understand the hydraulic characteristics of plunge pool deeply. The calculated and the measured pressure distributions on the pool bottom are compared and in good agreement.

关键词： Computer simulation Flood control Flow of fluids Pressure distribution Three dimensional

AERATION EFFECT OF SUBMERGED JET ON HYDRAULIC CHARACTERISTICS

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Journal of Hydrodynamics 2002年第3期14卷 35-39页

作者： liu, shan-jun Xu, Wei-Lin Wang, Wei Qu, Jing-Xue Hydraulics Lab. of High Speed Flows Sichuan Univ. Chengdu 610065 China

A water-air two-phase turbulence mathematical model was proposed, The mass-weighted average was adopted for velocity, air mass fraction and turbulent parameters. The algebraic stress equation was used to calculate the Reynolds stress. The pulsating flux of air mass fraction was simulated by employing the concept of the eddy viscosity. The numerical simulation of aerated flow in plunge pool shows that, for the same depth, aeration may decrease the time-averaged pressure on pool floor and increase slightly the turbulent intensity. The computed concentration and pressure distributions coincide with the experimental data.

关键词： Computer simulation Mathematical models Pressure distribution Turbulent flow Two phase flow

THEORETICAL AND EXPERIMENTAL STUDIES OF HYDRAULIC CHARACTERISTICS OF DISCHARGE TUNNEL WITH VORTEX DROP

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Journal of Hydrodynamics 2010年第4期22卷 582-589页

作者： CHEN Hua-yong XU Wei-lin DENG jun NIU Zhi-pan liu shan-jun WANG Wei State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065 China

The velocities at given points in the volute chamber,the contracted section and the vertical dropshaft of a discharge tunnel with vortex drop were measured by a small specially designed L-shaped tube,as Laser Doppler Velocimetry（LDV） or Particle Image Velocimetry（PIV） would not work there due to the special structure of the discharge tunnel with vortex *** empirical formulas were proposed to predict the velocities and the angles of the velocities made with the vertical direction θ.The theoretical analysis results were in good agreement with experimental ***,the method proposed in this paper can be used to analyze related characteristics of discharge tunnels with vortex ***,different model scales were considered to predict the cavitation characteristics on the wall of a dropshaft in practical engineering.

关键词： discharge tunnel with vortex drop dropshaft velocity wall pressure cavitation

EXPERIMENTAL INVESTIGATION OF EMERGENCY GATE SHUTTING FOR ORIFICE TUNNEL

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Journal of Hydrodynamics 2002年第3期14卷 29-34页

作者： Wang, Wei Yang, Yong-Quan Xu, Wen-Lin liu, shan-jun Diao, Ming-jun Zhang, Jian-Min Hydraulics Lab. of High Speed Flows Sichuan Univ. Chengdu 610065 China

In the process of the emergence gate shutting of one orifice tunnel, a big noise and great vibration may be observed in the mid gate chamber. In order to guarantee the working safety of orifice tunnels, an experimental investigation is carried out in Sichuan University. In the investigation, the fluctuation pressure along the tunnel and the wind velocity in the entry of emergency gate are measured. In the mean time, the fluid state in orifice tunnel is carefully observed and analyzed. The reasons of the noise and vibration in the mid gate chamber are found out and some countermeasures are presented in this paper. The conclusions are useful to the orifice tunnels with high water head and huge discharge.

关键词： Pressure measurement Tunnels Velocity Vibrations (mechanical) Wind

NUMERICAL SIMULATION OF TURBULENT FLOW THROUGH THROAT-TYPE ENERGY-DISSIPATORS

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Journal of Hydrodynamics 2002年第3期14卷 135-138页

作者： Dong, Jian-Wei Xu, Wei-Lin Deng, jun liu, shan-jun Wang, Wei Qu, Jing-Xue Hydraulics Lab. of High Speed Flows Sichuan Univ. Chengdu 610065 China

The flow through the throat-type energy-dissipators is calculated by using an axis-symmetrical K-Ε turbulence model. The velocity field, the pressure field and the distributions of turbulent energy and its dissipation rate are acquired. The energy dissipation through the throat-type energy-dissipators can be seen in detail. The calculated pressure distribution is compared with the measured and is in good agreement. The results are useful to understand deeply the flow characteristics of the throat-type energy-dissipators.

关键词： Computer simulation Flow of fluids Pressure distribution Turbulent flow Velocity

Heat-Clearing Chinese Medicines in Lipopolysaccharide-Induced Inflammation

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Chinese Journal of Integrative Medicine 2020年第7期26卷 552-559页

作者： LU Zi-bin OU Jin-ying CAO Hui-hui liu jun-shan YU Lin-zhong Traditional Chinese Pharmacological Laboratory Third Level Research Laboratory of State Administration of Traditional Chinese MedicineSchool of Traditional Chinese MedicineSouthern Medical UniversityGuangzhou(510515)China

Lipopolysaccharide(LPS)-induced inflammation causes massive threatening diseases,such as sepsis,acute lung injury and multiple organ dysfunction *** treatment to prevent inflammation is crucial in LPS-induced inflammatory ***-clearing Chinese medicines(CMs)have been used to ameliorate LPS-induced inflammation in China for ***-clearing CMs regulate inflammatory pathways,thereby inhibiting the release of inflammatory *** review aimed to introduce promising heat-clearing CMs countering LPS-induced inflammation in the last 5 years,exploring the underlying molecular mechanisms.

关键词： Chinese medicine heat-clearing lipopolysaccharide inflammation review

HYDRODYNAMIC UPLIFT FORCE AND STABILITY OF ARCIFORM PLUNGE POOL

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Journal of Hydrodynamics 2002年第3期14卷 8-12页

作者： Xu, Wei-Lin Wang, Wei liu, shan-jun Qu, Jing-Xue Diao, Ming-jun Hydraulics Lab. of High Speed Flows Sichuan Univ. Chengdu 610065 China

Compared with general trapeziform plunge pools, an arciform plunge pool has its advantages, e.g. less excavate quantity, higher stability, etc. In this paper, the hydrodynamic pressure distribution on the soleplate of the arciform plunge pool is measured under a relatively dangerous condition of operation. The result is helpful to the design of the arciform plunge pool. The result also shows that the difference between the maximum and the minimum pressures on the upward surface of the soleplate may cause an additional uplift force on the soleplate under certain condition and should be taken into consideration in the uplift force calculation of the soleplate. The scour experiment verifies the higher stability of the arciform plunge pool.

关键词： Energy dissipators Hydrodynamics Pressure distribution Pressure measurement Stability Uplift pressure

SCALE EFFECT OF I MPINGING PRESSURE CAUSED BY SUBMERGED JET

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Journal of Hydrodynamics 2005年第4期17卷 478-482页

作者： TIAN Zhong XU Wei-lin WANG Wei liu shan-jun DONG Jian-wei State Key Hydraulics Laboratory of High Speed Flows Sichuan University Chengdu 610065 China Military Oil Supply Engineering Department Logistical Engineering University Chongqing 400016China

The characteristics of the impinging pressure at the jet equipment where the maximum jet velocity can reach 50m/s were studied. By comparing the impinging pressure with the one measured at the low velocity conditions, two conclusions of the scale effect are drawn： firstly, the velocity attenuation degree is smaller than that of low velocity jet, and secondly, the relative impinging width is narrower than that of low-velocity jet. The reasons of the scale effect of the impinging pressure were elucidated through numerical simulation.

关键词： scale effect impinging pressure high-velocity jet numerical simulation