Wyniki wyszukiwania - Biblioteka Nauki

1

Modeling of a Water Flow Over Stepped Spillways

100%

Kherbache K. , Chesneau X. , Abide S. , Benmamar S.

Machine Dynamics Research

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2013

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tom Vol. 37, No. 1

51-68

EN

In this work, a numerical analysis of the flow over a stepped spillway is performed. The free surface flow is described by the Reynolds Averaged Navier-Stokes equation (RANS) coupled to k-ε model. These equations are solved using a commercial software based on the finite volume scheme and the VOF method. We analyzed the influence of the steps shape and water flow rate on velocity, turbulence dissipation rate and pressure distributions. In this, we found that the maximum values of the static pressure and the turbulence dissipation rate increase as the discharge increases and the main flow velocity is greater than the one of the secondary flow.

2

Eksperymentalne badania przepływu zgazowanej wody przez ośrodek porowaty

100%

Filek K.

Górnictwo / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie

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2003

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tom R. 27, z. 2

101-109

PL

W pracy przedstawiono wyniki pomiarów wydatku i rozkładu ciśnienia cieczy z rozpuszczonym w niej gazem, w różnych warunkach przepływu przez ośrodek porowaty. Zbadano przepływ wody z dwutlenkiem węgla, określając wpływ jej temperatury oraz zmienność zjawiska w czasie. Wpływ temperatury wody określono badając zjawisko jej przepływu w dwudziestu wariantach: przy pięciu wartościach ciśnienia CO2 i czterech wartościach temperatury wody. Zmienność w czasie określono dokonując pomiarów w odstępach jednogodzinnych przy tych samych pięciu wartościach ciśnienia CO2. Uzyskane wyniki przedstawiono w formie wykresów rozkładów ciśnienia wody wzdłuż kolumny wypełnionej ośrodkiem porowatym, otrzymanych przy różnych ciśnieniach dwutlenku węgla i różnych temperaturach wody oraz wykresów wydatku zgazowanej wody w funkcji temperatury wody i w funkcji czasu trwania zjawiska.

EN

The flow of water with carbon dioxide was tested, determining the influence of its temperature and variability of the phenomenon in time. The influence of water's temperature was determined by examining the phenomenon of its flow in 20 variants, with 5 values of pressure CO2 and 5 values water's temperature. Variability in time was determined by measuring pressure of CO2 in 1-hour intervals for the same 5 values. The results obtained are shown in graphs presenting the distribution of water's pressure along the column filled with a porous medium, obtained for different pressures of CO2 and different water's temperatures and also in the form of graphs of saturated water flow rate in the function of water temperature and in the function of this phenomenon.

3

Indicators of Variability of Water Flow Rate in the Piwonia River

100%

Grzywna A.

Journal of Ecological Engineering

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2019

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tom Vol. 20, nr 7

205--210

EN

The paper presents the variability of the Piwonia River flows in the Parczew profile (catchment area of 391 km2) in hydrological years 2009/10–2015/16. On the basis of the monthly flow and daily water level measurements, flow-level curves and hydrograms of water flows were drawn. The analysis of the weather conditions in the catchment area showed that in the analyzed period there were two very wet years (2010, 2014), three wet years (2011, 2013, 2016), one normal year (2012) and one dry year (2015). The total of annual precipitation in very wet years was 150 mm (130% of the norm) higher than the average for multi-years, and in the dry year it was 60 mm (86% of the norm) lower. The intensity of instantaneous flows ranged from 0.26 m3∙s-1 in 2015 to 5.5 m3∙s-1 in 2010. The average annual flow of the river in multi-years was SSQ = 1.68 m3∙s-1 and ranged from 1.19 m3∙s-1 in 2015 (dry in terms of precipitation) to 2.13 m3∙s-1 in 2010 (very wet). The direct reasons for the variability of river flows are: weather conditions, retention capacity of lakes and fish ponds, and exploitation of the hydrotechnical structures. The hydrological year 2014/15 was characterized by the highest variability of flows, while the lowest variability was recorded in the hydrological year 2010/11.

4

Stopnie regulacyjne z wydłużonym czy zawężonym przelewem?

100%

Mokwa M. , Pietraszko K.

Gospodarka Wodna

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2009

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tom Nr 3

116-121

PL

Artykuł przedstawia argumentację przemawiającą za stosowaniem stopni z wydłużonym przelewem jako budowli, które stwarzają korzystniejsze warunki przepływu wody i rozproszenia energii i które okazały się budowlami mniej podatnymi na uszkodzenia.

EN

The article puts forward arguments for the use of degrees with elongated overflow as constructions that create better conditions of water flow and energy diffusion and that are less prone to damages.

5

High resolution seismic investigations for the determination of water flow directions during sulphur deposits exploitation

100%

Dec J.

Acta Geophysica

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2010

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tom Vol. 58, no. 1

5-14

EN

This paper shows the results of seismic research on some problems of sulphur in-situ mining. The difficulties during exploitation were mainly connected with the lack of detailed information on the structure and tectonics of deposit and overburden strata. This kind of information could be obtained using the High Resolution Seismic method. The use of seismic method allows to determine the range of subsidence provoked by well mining of sulphur. It is very important to undertake the measurements before exploitation, because the comparison of seismic sections before and during exploitation creates a possibility of determining the process of changes in the structure of the deposit and overburden strata. Another problem is a possibility of determining the source of uncontrolled flows of technological water. The water saturated zones are observed on seismic records as zones without reflections and with decay of seismic energy. Two examples of the seismic investigation conducted on the well mining of sulphur area are presented. Both are connected with the danger to main road on the surface caused by uncontrolled flow of technological water.

6

Investigations of hydraulic operating conditions of air lift pump with three types of air-water mixers

88%

Kalenik M.

Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation

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2015

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tom 47

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nr 1

7

A model of fresh and mineral water flow in the Kryniczanka catchment area with the use of Visual MODFLOW software package

88%

Duńczyk L.

Biuletyn Państwowego Instytutu Geologicznego

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2001

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tom nr 396

42-42

8

Harmonic analysis of tides in Admiralty Bay

88%

Catewicz Z. , Kowalik Z.

Oceanologia

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1983

|

tom 15

9

Modélisation numérique spatiale d'écoulement de l'eau souterraine sur le périmètre alimenté par l'infiltration

88%

Krol P.

Annals of Warsaw Agricultural University. Land Reclamation

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2004

|

tom 35a

10

Simulation of density dependent transport in groundwater

88%

Maciejewski S. , Zaradny H.

Archives of Hydro-Engineering and Environmental Mechanics

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2003

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tom Vol. 50, nr 3

207-218

EN

A mathematical model of water flow and transport of chemical substances is presented in the paper. This model takes into account the influence of variable density and viscosity of water caused by variable solute concentration in soil. A solution of the problem of water flow and solute transport was sought using numerical methods. A finite elements method for solution of water flow equation and Monte-Carlo method to simulate solute transport were applied. Advantages of the presented model are illustrated on the example of water flow and salt transport in two dimensional ground profile in the region of Puck Bay. The geology of this profile is taken from Jankowska et al (1994). Obtained results from the proposed model are qualitatively conformable with observations in situ.

11

Wave-induced set-up and flow over shoals and coral reefs. Part 1. A simplified bottom geometry case

88%

Massel S. R. , Brinkman R. M.

Oceanologia

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2001

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tom No. 43 (4)

373-388

EN

An analytical approach was used to model the wave-induced set-up and flow through simple shoal geometry when water depth is a linear function of the distance. Two different approaches were applied to parameterize the energy dissipation due to wave breaking. The resulting set-up height and flow velocity were determined and their dependence on the geometry of the shoal and offshore forcing was demonstrated. The extension of the solution to a more complicated bathymetry and verification against the experimental data will be given in the second part of the paper.

12

Przykłady regulacji rzek w Królestwie Polskim. Część 1

75%

Rutkowski M.

Gospodarka Wodna

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2019

|

tom Nr 4

27--30

PL

Przedstawiono informacje o pracach wykonywanych na kilku rzekach, w celu ułatwienia przepływu wody i ograniczenia zagrożenia powodziami w okresie Królestwa Polskiego. Decyzje dotyczące prac regulacyjnych na Pilicy podjęte zostały w 1815 r. W latach następnych podjęto decyzje o rozpoczęciu robót na Bzurze, Warcie i Bugu. W ogólnym zarysie przedstawiono zakres i rodzaj realizowanych robót, zaprezentowano także organizację tych prac oraz zasady ich finansowania.

EN

The article presents information on works carried out on several rivers and aiming at facilitation of water flow and mitigation of flood risk in the Kingdom of Poland period. Decisions regarding regulation of the Pilica River were taken in 1815. In subsequent years, it was decided to start works on Bzura, Warta and Bug. The article presents a general overview of the scope and type of works, as well as their organisation and financing principles.

13

Praca chłodni kominowych w warunkach zmiennego obciążenia cieplnego i hydraulicznego

75%

Stechman A.

Gospodarka Paliwami i Energią

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2001

|

tom nr 12

18-21

PL

Przedstawiono problemy towarzyszące pracy chłodni kominowych przy szeroko zmiennym obciążeniu cieplnym i hydraulicznym. Stosując strefowy wodorozdział, instalację natryskową i rurociągi bezpośredniego zrzutu, połączone w system, możliwa jest regulacja temperatury wody ochłodzonej, zapewniająca bezpieczną pracę chłodni w okresie zimowym.

EN

Natural draught cooling towers performance problems in wide change of heat duty and water flow has been pressented. Water distribution system with separated zones together with spraying system and by-pass pipes are used to control recooled water temperature and antifreezing protection.

14

Variability of water flow in the Ezcurra Inlet

75%

Catewicz Z.

Oceanologia

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1983

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tom 15

15

Stable isotope deuterium as a natural tracer of mixing processes in rivers

75%

Palige J. , Ptaszek S. , Zimnicki R. , Chmielewski A. G. , Wierzchnicki R.

Nukleonika

|

2008

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tom Vol. 53, No. 2

63-67

EN

The possibility of application of naturally existing differences in isotope contents 18O/16O, 2H/1H in waters for investigation of transport and mixing of various waters in the tributary-river system is presented. Experiments carried out on the Bug-Narew rivers-Zegrze Lake and the BugoNarew-Vistula rivers systems have indicated that the hydrogen isotope ratio 2H/1H can be used as an intrinsic tracer of natural mixing processes occurring in rivers. The IRMS methodology was used for isotope ratio measurement of water samples. The degrees of water mixing as a function of distance from the confluence point of rivers were determined. The obtained results indicate that in water systems where the natural differences in ?2H are higher than 5‰ this technique can replace the time-consuming and expensive dye (or radiotracer) dispersion tests for evaluation of pollutant transport in rivers.

16

Przykłady regulacji rzek w Królestwie Polskim. Cześć II

75%

Rutkowski M.

Gospodarka Wodna

|

2019

|

tom Nr 5

25--28

PL

Przedstawiono informacje o pracach wykonywanych na kilku rzekach, w celu ułatwienia przepływu wody i ograniczenia zagrożenia powodziami w okresie Królestwa Polskiego. Decyzje dotyczące prac regulacyjnych na Pilicy podjęte zostały w 1815 r. W latach następnych podjęto decyzje o rozpoczęciu robót na Bzurze, Warcie i Bugu. W ogólnym zarysie przedstawiono zakres i rodzaj realizowanych robót, zaprezentowano także organizację tych prac oraz zasady ich finansowania.

EN

The article presents information on works carried out on several rivers and aiming at facilitation of water flow and mitigation of flood risk in the Kingdom of Poland period. Decisions regarding regulation of the Pilica River were taken in 1815. In subsequent years, it was decided to start works on Bzura, Warta and Bug. The article presents a general overview of the scope and type of works, as well as their organisation and financing principles.

17

Sediment transport mechanics

75%

Ballio F. , Tait S.

Acta Geophysica

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2012

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tom Vol. 60, no. 6

1493-1499

EN

The Editor of Acta Geophysica and the Guest Editors wish to dedicate this Topical Issue on Sediment Transport Mechanics to the memory of Stephen Coleman, who died recently. During his career, Stephen had made an outstanding scientific contribution to the topic of Sediment Transport. The level of his contribution is demonstrated in the paper by Aberle, Coleman, and Nikora included in this issue, on which he started working before becoming aware of the illness that led to his untimely death. For scholars and colleagues Stephen remains an example of intellectual honesty and scientific insight.

18

Projektowanie przejść drogowych przez cieki wodne w stanie Maryland (USA) - system organizacji i podstawowe wymagania

75%

Kosicki A. J.

Gospodarka Wodna

|

2009

|

tom Nr 7

261-268

PL

Artykuł jest pierwszym z cyklu omawiającego metody projektowania przekroczeń drogowych cieków wodnych w USA na podstawie doświadczeń stanu Maryland. Autor pracuje w USA od 1982 r. i od początku zajmuje się tymi zagadnieniami. Celem całej serii jest przedstawienie ewolucji w projektowaniu drogowych przekroczeń wodnych na przestrzeni ostatnich 20 lat oraz zaprezentowanie obecnych zasad stosowanych w stanie Maryland.

EN

The article is devoted to the system of water resources management in Spain. The limited availability of water resources and the necessity to share them with neighboring Portugal constitute serious problems for this country. Additionally, the availability of water resources is a factor limiting the possibilities of economic development of Spain.

19

Maintaining the water consumption, in an urban system: A probabilistic approach is applied

75%

Selmani Bouayoune K. , Boudi E. M. , Bachir A.

|

20

On the instabilities of estimated distributions of the POT (Peak Over Threshold) low flow characteristics

75%

Jakubowski W.

Meteorology Hydrology and Water Management. Research and Operational Applications

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2015

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tom 03

|

nr 2

EN

In a certain stream gauge profile, consider the low flow flows determined with the POT (Peak Over Threshold) method. Each of the flows can be described by three characteristics – deficit, duration and minimal flow. Values of the three-dimensional random variable depend on the choice of truncation level Qg (threshold flow) – POT method parameter. It is typically assumed that the threshold level is included within the range from Q95% to Q60% (Tallaksen, van Lanen 2004). However, in computational practice the Qg value is determined at the level of either Q90% to Q70%. This choice is made mainly from the hydrological (not statistical) point of view. In this paper the influence of the threshold flow on the form of estimated distributions of each of the above three characteristics is considered. The following distributions are chosen: − GEV (generalised extreme value distribution) – while examining the distribution of extremes; − log-normal – in the non-extreme case. In each of the examined stream gauge profiles the following algorithm was used: 1. from the curve of duration sums, two flow values Q90% and Q55% are chosen 2. for each flow from the range (Q90%, Q55%), using the Zelenhasić method (1987), a three-dimensional sequence is determined of observed deficits, durations and minimal flow values; 3. for each of the one-dimensional sequences, the parameters of the above distributions are estimated. The variability of the estimated quantiles and their intervals of confidence were shown with the example of three gauge profiles – Kuripapango (New Zealand), Bogusław (Prosna) and Bystrzyca Kłodzka (Nysa Kłodzka).