Study on the Effect of Regulation Project of Bifurcation on Flow Characteristics of Sink Reach of River Flowing into the Lake

2013 ◽  
Vol 791-793 ◽  
pp. 2188-2191
Author(s):  
Jun Chen ◽  
Ai Feng Huang ◽  
Gao Hu Sun ◽  
Yong Tao Li

In order to research on the influence of regulation project, a two-dimensional flow mathematical model was adopted, and the change of diversion ratio, main stream line, water level, velocity of sink reach of river flowing into the lake were analyzed, the results were shown as follows: if the project built, the main stream line of bifurcation would move to the left side, and the diversion ratio of which would be increased by 0.54%. At the left side of the bifurcation, the water level would reduce obviously, and the maximum reduction of which would be 0.178m, and the velocity would increase, and maximum increase of which would be 1.0m/s. At the right side of the bifurcation, the water level would raise and the velocity would reduce, and the maximum reduction of which would be 1.667m/s. The point where water flow colliding with the left bank would change, and the velocity of point would be increased by 0.413m/s. The flow pattern would be smooth-going, the navigation condition of river would be improved, and the effect of project on flood control would be less.

2020 ◽  
Vol 198 ◽  
pp. 04008
Author(s):  
Hua Ge ◽  
Chunyan Deng

At present, the traffic pressure of Nanchang city, the capital of Jiangxi province, is increasing. The increasing demand for the construction of river crossing channel requires strengthening the research on the flow characteristics of the tail reach of Ganjiang River where Nanchang is located. In this paper, the south section of Nanchang city at the tail end of Ganjiang River was taken as the research object. By applying the plane two-dimensional flow mathematical model as the technical means, and using the latest measured topographic and hydrological data in 2020 to verify the model, the flow movement characteristics of the studied river section were calculated and analysed. The results show that the water surface gradient is slow, the flow field is smooth, the flow velocity is small, and the sediment is easy to deposit in this reach, which is easy to threaten the flood control of the river section.


2014 ◽  
Vol 1044-1045 ◽  
pp. 438-443
Author(s):  
Chun Guang Li ◽  
Cheng Yang

In order to predict the sedimentation deposition in the Shuidonggou reservoir in next few years, the flow in this reservoir is studied using the two dimensional (2D) hydraulic mathematical model. The governing equations of the model are discredited with finite volume method (FVM) on unstructured grids, and the 2-D flow movement are simulated under several different conditions. The results showed that: when the amount of the water inflow and the water drawn unchanged, as the water level drops, water flow velocity increases in the reservoir; at high water level (1179 m), the left bank of the south side of the intake eroded; at low water level (1174.4m), north and south sides of the mainstream of water have a recirculation zone; when the water level is constant, with the increase of the amount of water, the recirculation zone on the right side of the intake became smaller and close to the water intake.


2012 ◽  
Vol 212-213 ◽  
pp. 725-730
Author(s):  
Ji Qing Li ◽  
Di Shen ◽  
Ai Jing Wang ◽  
Yu Shan Zhang

the layout and the characteristics of the cascade reservoirs and hydropower stations in the upper reaches of the Yellow River, determine that cascade hydropower stations scheduling must be operated based on the joint operation between Longyangxia and Liujiaxia cascade hydropower stations, especially on flood control operation. This paper deeply analyzes design flood storage area of the Liujiaxia composition and Longyangxia-Liujiaxia joint flood regulating principle on the basis of analyzing and calculating each ten-day design flood of the Tangnaihai above main stream and the intervals. Therefore, the reasonable combination of interval flood and the process of Longyangxia reservoir flood discharge is confirmed, and thereby, studying Liujiaxia reservoir inflowing design flood under a controlling operation of flood limited water level for a period of ten-day to ensure the safety of Liujiaxia reservoir flood control.


Author(s):  
WILLIAM GARDENER

Prince Henri d'Orleans, precluded by French law from serving his country in the profession of arms, had his attention turned early towards exploration. In 1889, accompanied by the experienced traveller Gabriel Bonvalet, he set out from Paris to reach Indo-China overland by way of Central Asia, Tibet and western and south western China. The journey made contributions in the problems of the whereabouts of Lap Nor and the configuration of the then unexplored northern plateau of Tibet; and in botany it produced some species new to science. The party reached Indo-China in 1890. In 1895, having organised an expedition better equipped for topographical survey and for investigations in the fields of natural history and ethnography, Prince Henri set out from Hanoi with the intention of exploring the Mekong through the Chinese province of Yunnan. After proceeding up the left bank of the Salween for a brief part of its course and then alternating between the right and left banks of the Mekong as far up as Tzeku, the party found it advisable to enter Tibet in a north westerly direction through the province of Chamdo and instead crossed the south eastern extremity of the country, the Zayul, by a difficult track which led them to the country of the Hkamti Shans in present day Upper Burma, and thence to India completing a journey of 2000 miles, "1500 of which had been previously untrodden" (Prince Henri). West of the Mekong, the journey established that the Salween, which some geographers had claimed took its rise in or near north western Yunnan, in fact rose well north in Tibet, and that, contrary to previous opinions, the principal headwater of the Irrawaddy rose no further north than latitude 28°30'. Botanical collections were confined to Yunnan, where the tracks permitted mule transport, and they produced a number of species new to science and extended the range of distribution of species already known.


2019 ◽  
Vol 70 (11) ◽  
pp. 3903-3907
Author(s):  
Galina Marusic ◽  
Valeriu Panaitescu

The paper deals with the issues related to the pollution of aquatic ecosystems. The influence of turbulence on the transport and dispersion of pollutants in the mentioned systems, as well as the calculation of the turbulent diffusion coefficients are studied. A case study on the determination of turbulent diffusion coefficients for some sectors of the Prut River is presented. A new method is proposed for the determination of the turbulent diffusion coefficients in the pollutant transport equation for specific sectors of a river, according to the associated number of P�clet, calculated for each specific area: the left bank, the right bank and the middle of the river.


2021 ◽  
Vol 193 (1) ◽  
pp. 43-54
Author(s):  
Yasuda Mitsuyoshi ◽  
Funada Tomoya ◽  
Sato Hisaya ◽  
Kato Kyoichi

Abstract As chest x rays involve risks of patients falling, radiologic technologists (technologists) commonly assist patients, and as the assistance takes place near the patients, the eye lenses of the technologists are exposed to radiation. The recommendations of the International Commission on Radiological Protection suggest that the risk of developing cataracts due to lens exposure is high, and this makes it necessary to reduce and minimize the exposure. The present study investigated the positions of technologists assisting patients that will minimize exposure of the eye lens to radiation. The results showed that it is possible to reduce the exposure by assisting from the following positions: 50% at the sides rather than diagonally behind, 10% at the right side of the patient rather than the left and 40% at 250 mm away from the patient. The maximum reduction with radiation protection glasses was 54% with 0.07 mmPb and 72% with 0.88 mmPb.


2021 ◽  
Vol 13 (9) ◽  
pp. 4857
Author(s):  
Zitong Yang ◽  
Xianfeng Huang ◽  
Jiao Liu ◽  
Guohua Fang

In order to meet the demand of emergency water supply in the northern region without affecting normal water transfer, considering the use of the existing South-to-North Water Transfer eastern route project to explore the potential of floodwater resource utilization in the flood season of Hongze Lake and Luoma Lake in Jiangsu Province, this paper carried out relevant optimal operating research. First, the hydraulic linkages between the lakes were generalized, then the water resources allocation mode and the scale of existing projects were clarified. After that, the actual available amount of flood resources in the lakes was evaluated. The average annual available floodwater resources in 2003–2017 was 1.49 billion m3, and the maximum available capacity was 30.84 billion m3. Then, using the floodwater resource utilization method of multi period flood limited water levels, the research period was divided into the main flood season (15 July to 15 August) and the later flood season (16 August to 10 September, 11 September to 30 September) by the Systematic Clustering Analysis method. After the flood control calculation, the limited water level of Hongze Lake in the later flood season can be raised from 12.5 m to 13.0 m, and the capacity of reservoir storage can increase to 696 million m3. The limited water level of Luoma Lake can be raised from 22.5 m to 23.0 m (16 August to 10 September), 23.5 m (11 September to 30 September), and the capacity of reservoir storage can increase from 150 to 300 million m3. Finally, establishing the floodwater resource optimization model of the lake group with the goals of maximizing the floodwater transfer amount and minimizing the flood control risk rate, the optimal water allocation scheme is obtained through the optimization algorithm.


Proceedings ◽  
2019 ◽  
Vol 48 (1) ◽  
pp. 30
Author(s):  
Luis Hamilton Pospissil Garbossa ◽  
Argeu Vanz ◽  
Matias Guilherme Boll ◽  
Hamilton Justino Vieira

The increasing frequency of extreme storm events has implications for the operation of sewer systems, storm water, flood control monitoring and tide level variations. Accurate and continuous monitor water level monitoring is demanded in different environments. Piezoelectric sensors are widely used for water level monitoring and work submerged in waters subject to the presence of solid particles, biological fouling and saltwater oxidation. This work aimed to develop a simple, low-cost methodology to protect sensors over long-term deployment. The results show that simple actions, costing less than 2 EUR, can protect and extend the lifecycle of equipment worth over 2000 EUR, ensuring continuous monitoring and maintaining quality measurements.


Processes ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 1295
Author(s):  
Anghong Yu ◽  
Chuanzhen Wang ◽  
Haizeng Liu ◽  
Md. Shakhaoath Khan

Three products hydrocyclone screen (TPHS) can be considered as the combination of a conventional hydrocyclone and a cylindrical screen. In this device, particles are separated based on size under the centrifugal classification coupling screening effect. The objective of this work is to explore the characteristics of fluid flow in TPHS using the computational fluid dynamics (CFD) simulation. The 2 million grid scheme, volume fraction model, and linear pressure–strain Reynolds stress model were utilized to generate the economical grid-independence solution. The pressure profile reveals that the distribution of static pressure was axisymmetric, and its value was reduced with the increasing axial depth. The maximum and minimum were located near the tangential inflection point of the feed inlet and the outlets, respectively. However, local asymmetry was created by the left tangential inlet and the right screen underflow outlet. Furthermore, at the same axial height, the static pressure gradually decreased along the wall to the center. Near the cylindrical screen, the pressure difference between the inside and the outside cylindrical screen dropped from positive to negative as the axial depth increased from −35 to −185 mm. Besides, TPHS shows similar distributions of turbulence intensity I, turbulence kinetic energy k, and turbulence dissipation rate ε; i.e., the values fell with the decrease in axial height. Meanwhile, from high to low, the pressure values are distributed in the feed chamber, the cylindrical screen, and conical vessel; the value inside the screen was higher than the outer value.


2008 ◽  
Vol 68 (4) ◽  
pp. 799-805 ◽  
Author(s):  
EK. Resende ◽  
DKS. Marques ◽  
LKSG. Ferreira

The "tucunaré", Cichla piquiti, an exotic Amazonian fish has become established along the left bank of the Paraguay River in the Pantanal. It was introduced by escaping from culture ponds in the Upper Piquiri River and spread downstream, along the lateral flooded areas of that river, continuing through the clear waters of the left bank of the Paraguay River and reaching south as far as the Paraguai Mirim and Negrinho rivers. Adult spawners have been found in the region, meaning that it is a self-sustained population. Reproduction occurs in the period of low waters. They were found feeding on fishes of lentic environments belonging to the families Characidae, Cichlidae and Loricariidae. Until the end of 2004, its distribution was restricted to the left bank of the Paraguay River, but in March 2005, some specimens were found on the right bank, raising a question for the future: what will be the distribution area of the tucunaré in the Pantanal? Information about its dispersion is increasing: it is known to be in the Tuiuiú Lake, Pantanal National Park and in the Bolivian Pantanal, all of them on the right bank of the Paraguay River. The hypothesis that the "tucunaré" could not cross turbid waters, such as in the Paraguay River, was refuted by these recent findings. Possibly, the tucunaré's capacity to lay more than one batch of eggs in a reproductive period, as well as its care of eggs and young, lead them to establish themselves successfully in new environments, as has been observed in the Pantanal and other localities.


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