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A HYBRID MODEL FOR SIMULATING VELOCITY FIELD OF A RIVER WITH COMPLEX GEOMETRY PLUNGED BY MULTIPLE JETS

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Journal of Hydrodynamics 2006年第6期18卷 752-759页

作者： LI Lian-xia liao hua-sheng LI Tian-xiang State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065China

A hybrid model that combines both physical and numerical models was employed to simulate the velocity field in a river area in complex geometry with multiple plunging jets. The simulation was based on experiments concerning energy dissipation and scour prevention at the Xiluodu Hydropower Station on the Yangtze River. The calculated results indicate that the complex geometry of the river area has a significant influence on the velocity field, especially on the circulation flow pattern at upstream and downstream of the plunging area and on the asymmetric characteristics of the spiral flow near both banks. The scour characteristics of the downstream river bed caused by the multiple jets were also predicted and analyzed according to the characteristics of the calculated velocity field. The good agreement between the simulated and experimental results indicates that the hybrid model can be used to effectively solve complicated 3-D problems with complex geometric and inlet conditions. Such problems may not easily be solved by using either a physical or a numerical model alone, and therefore the method presented in this article is considered to be a practical and effective way of dealing with this kind of problems.

关键词： hybrid models turbulence model scour multiple jets

EXPERIMENTAL STUDY ON A NEW TYPE OF AERATOR IN SPILLWAY WITH LOW FROUDE NUMBER AND MILD SLOPE FLOW

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Journal of Hydrodynamics 2009年第3期21卷 415-422页

作者： SU Pei-lan liao hua-sheng QIU Yue LI Chen-juan State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065 China

Experimental study on aeration characteristics of various aeration devices was conducted in the spillway tunnel of the Pubugou hydropower project, Sichuan Province, China. It is shown by comparison that the new type of aeration device, namely, the aerator with a trapezoidal-shaped slot and a steep-slope section（ATSS）, can avoid water accumulation in the cavity of the aeration device in the project, thus can effectively solve the backwater problems arising from this project and be used for a wide range of different water levels, without any drain facilities. Above the water level of 840 m, the water contained in the cavity can be eliminated completely, which means that the recommended new type of aerator can meet the aeration demands in the spillway of the project with low Froude number and may be of practical significance and of interest to other projects with similar types of aeration devices.

关键词： aeration device a trapezoidal-shaped slot and a steep-slope section(ATSS) air entrainment cavitation

EXPERIMENTAL INVESTIGATION ON SOUND SPEED PROPAGATING THROUGH HIGH SPEED AERATED FLOW IN OPEN CHANNEL

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Journal of Hydrodynamics 2002年第3期14卷 97-101页

作者： liao, hua-sheng Xu, Wei-Lin Yang, Yong-Quan Wu, Chi-Gong Hydraulics of High Speed Flows Sichuan Univ. Chengdu 610065 China

An experiment concerning the sound propagation in aerated open channel flow was designed and conducted in a variable slope chute. The acquisition of sound data was done by the hydro-phones installed into the bottom wall of the chute. The data were analyzed and processed by the tape recorder and a 3562A analyzer. The primary experimental results indicate that the sound speed in aerated flow is varied with the air concentration and highly lower than each of the sound speed in pure water or air. As released by the derived theoretical formula, the minimum sound of 24 m/s in aerated flow happened when the air concentration achieved to 50%. This result shows that the compressibility of high speed aerated flow should be considered when the air concentration is near to 50%. A criterion of compressibility of high speed aerated flow was also given in this paper.

关键词： Air Compressibility Open channel flow Tape recorders Two phase flow Water

Experimental investigation of the optimization of stilling basin with shallowwater cushion used for low Froude number energy dissipation

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Journal of Hydrodynamics 2015年第4期27卷 522-529页

作者：李连侠廖华胜刘达蒋胜银 State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Guangdong Research Institute of Water Resources and Hydropower Chengdu Municipal Engineering Design and Research Institute

Energy dissipations induced by the hydraulic jump and the trajectory jet are the most widely known as the two dissipation modes at the downstream of flood discharging structures, which are often considered quite different even contradictory. However, such two energy dissipators can be used jointly and harmonically. In this paper, a new type of stilling basin with a shallow-water cushion and a triangular bottom deflector is proposed based on two different scale physical model tests of the flood discharging tunnel No.2 of Luding hydropower project. The experimental results show that the flow regime of the hydraulic jump in the presented stilling basin with bottom deflector enjoys a good and stable performance within a large range of flow rates and the energy dissipation rate is considerably high as compared to the conventional stilling basin even at a low Froude number. The results also indicate that the stilling basin with triangular bottom deflector has a better performance in improving the potential cavitation erosion according to the analysis of the pressure and the cavitation number compared to the trapezoidal one. The proposed new type of shallow-cushion stilling basin with a shallow-water cushion can be applied in similar energy dissipation projects with low Froude number and large range of flow rates.

关键词： stilling basin shallow-water cushion energy dissipation low Froude number bottom deflector

NUMERICAL SIMULATION OF FLOW FOLD OF A RIVER WITH COMPLICATED BOUNDARIES

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Journal of Hydrodynamics 1996年第3期8卷 75-80页

作者： Xu Wei-lin liao hua-sheng (State Key Hydraulics Lab. of High Speed Flows, Sichuan Union University, Chengdu 610065, P. R. China) Sichuan Union Univ Chengdu China

The flow field of a river with complicated boundaries is simulated by dividing the calculation domain into several subdomains and using the depth-averaged k-ε turbulence model. The complicated topographic conditions in this paper include bar, confluence, narrow, bay and bend, etc. The lands emerging from the water surface are treated as blocked-off regions. The calculation is achieved at both the low and the high water levels. The velocity profiles along cross-sections are measured at the high water level in physical model. The calculated and measured velocity profiles are in agreement.

关键词： numerical simulation natural river complicated boundary

FIRST ORDER WALL VORTICITY FORMULA UNDER IRREGULAR MESH

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Journal of Hydrodynamics 1994年第3期6卷 47-52页

作者： liao hua-sheng, Wu Chi-gongChengdu University of Science and Technology, Chengdu 610065, P. R. China

In the engineering applications, flow problems with complicated geometrical shape of boundaries are of ten happen. Their boundary conditions should be given in precisely when doing the simulation of these type of flows because the regions near to the boundaries generally play an important role on the defined solutions. Using the vorticity-stream function form of the N-S equations as governing equations in the flow field simulation with irregular mesh, the determining/calculating wall vorticity under irregular mesh is very important. In this paper, one first order formula of wall vorticity under irregular mesh was derived based on the 2-D Taylor expansion and was tested numerically through an example of a flow with the Z type, shape of boundaries. A satisfactory result was found which was compared with one obtained by FEM.

关键词： vorticity-stream functions irregular mesh simulation.

THE　APPLICATION　OF　THE　AVERAGING　FINITE　DIFFERENCE　SCHEME　IN　THE　SIMULATION　OF　SEPARATED　FLOW

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Journal of Hydrodynamics 1994年第2期6卷 61-68页

作者： liao hua-sheng Wu Chi-gong (Chengdu University of Science and Technology, Chengdu 610065, P. R. China)

The authors' proposed averaging finite difference(AFD) theme bad been tested through the numerical example of a 2-D driven cavity flow, and its accuracy and feasibility have been indicated [1]. In this paper, the scheme was adopted to simulate the high Re flow with irregular boundaries so as to prove that it is also successful for this scheme to be used in the flow with irregular boundaries. A 2-D flow around a semicircular obstruction was taken as the calculation example and the first order wall vorticity formula for irregular mesh derived by the authors in Ref. [2] was Chosen to calculate the wall vorticity in the considered example. The salutations were carried out under the conditions: Re = 43, 100, 300, 500, 1000 and *** reasonable flow results and the curve of separated angle or reattached length VS Re were given. The results have shown that the AFD scheme can be extended to the simulations of separated flow with arbitrary boundaries and at high Reynolds number really.

关键词： finite difference scheme hash Reynolds number flow around semicircularobouction numerical simulation

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清代蚺城的约保

安徽史学 2006年第5期 91-97页

作者：廖华生厦门大学历史系福建厦门361005

蚺城约保的持续时间长、组织建构严密。约正和保正的素质较高,他们广泛参与地方公共事务,在蚺城公共管理中发挥了重要作用。由于清代地方财政与政府职能演变,约保成为由蚺城富户承担的徭役。徭役化给蚺城约保带来极大的负面影响,亦给官... 详细信息

蚺城约保的持续时间长、组织建构严密。约正和保正的素质较高,他们广泛参与地方公共事务,在蚺城公共管理中发挥了重要作用。由于清代地方财政与政府职能演变,约保成为由蚺城富户承担的徭役。徭役化给蚺城约保带来极大的负面影响,亦给官府干预提供了正当理由,从而保证了约保的正常运转。蚺城约保在地方公共事务中有一定的话语权,也表现出一定的独立性和自主性,但他们和地方官的关系大致无法突破“官府-徭役”的框架。

关键词：清代蚺城约保公共事务徭役化

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明清时期婺源的乡约与基层组织

安徽史学 2017年第6期 145-152页

作者：廖华生江西师范大学历史文化与旅游学院江西南昌330022

明清时期,婺源乡约在地方公共事务中的角色经历了明嘉靖朝的以教化为主,到隆庆五年(1571年)至明末里排共管,再到清代和保甲一道基本取代里排的演变过程。在此过程中,乡约的数量不断增加,乡约逐渐成为确立乡村宗族、村落权力格局和彰显... 详细信息

明清时期,婺源乡约在地方公共事务中的角色经历了明嘉靖朝的以教化为主,到隆庆五年(1571年)至明末里排共管,再到清代和保甲一道基本取代里排的演变过程。在此过程中,乡约的数量不断增加,乡约逐渐成为确立乡村宗族、村落权力格局和彰显社会身份的工具,其与保甲之间也逐渐密不可分。通过对婺源乡约与其他基层组织关系的梳理,我们可以对明清时期乡族组织的基本结构和运行机制有更深入的认识。

关键词：明清婺源乡约基层组织