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1

Structures of Turbulent Vortices in Floodplains of Compound Channels

Rimkus A.

Archives of Hydro-Engineering and Environmental Mechanics

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2016

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Vol. 63, nr 4

281--295

EN

In turbulent flows, several kinds of vortices and their structures are developed. After physical summation al velocities created by them, they intertwine, and the picture obtained from their measurement chronograms is mostly chaotic. Consequently, these structures become masked. It is therefore very difficult to investigate them and despite many studies performed so far, they have not been sufficiently explored. Favorable conditions for investigations of velocity measurement chronograms occurred when sufficient long intervals were observed, in which the above mentioned masking is minimal. In such intervals, the investigation of turbulent vortices and their structures becomes possible, and it has been performed to some degree. The results of these investigations of the compound channel were already discussed in two previously published articles. The first describes all vortices and their structures in the whole water flow of the compound channel. The second contains a detailed analysis of vortices and their structures in the central vertical of the main channel. This article, discuss investigations of coherent structures formed in the floodplain.

2

Analiza przyczyn zakłóceń pomiaru ClO2 na przykładzie gminnej Stacji Uzdatniania Wody

Kowalczyk A., Cieślak R., Chorzępa R.

Przegląd Elektrotechniczny

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2014

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R. 90, nr 1

161--163

PL

W pracy przedstawiono zasady oraz problemy związane z pomiarem dwutlenku chloru (ClO2), który jest podstawowym parametrem optymalnej dezynfekcji wody z zastosowanie tego rodzaju utleniacza. Na opisywanym obiekcie po montażu czujnika ClO2 nastąpił problem z zakłóceniami niewiadomego pochodzenia, które powodowały generowanie fałszywych alarmów o przekroczeniu dopuszczalnej wartości chloru. Praca przedstawia drogę dochodzenia do ustalenia przyczyny zakłóceń, sposób ich wyeliminowania i porównuje rzeczywiste zarejestrowane dane.

EN

The paper presents the rules and the problems associated with the measurement of chlorine dioxide (ClO2), which is a fundamental parameter of optimal water disinfection when such an oxidant is used. When ClO2 sensor was installed on the described object a problem with disturbances of unknown origin, which caused false alarms about the exceeding of the permissible value of chlorine, appeared. The paper presents the way of the investigation to determine the cause of disturbances, shows how to eliminate them, and compares the real recorded data.

3

Structure of Turbulent Vortices in a Compound Channel

Rimkus A.

Archives of Hydro-Engineering and Environmental Mechanics

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2012

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Vol. 59, nr 3-4

113-135

EN

In spite of many investigations performed on turbulent flows, their structure has not yet been sufficiently explored. The difficulty is that, when a detailed picture of the velocity field is necessary, the widely employed Particle Image Velocity (PIV) method can provide photos covering only a short interval of flow, which cannot include the largest structures of turbulent flow, and consequently these structures cannot be investigated. In this study, the author tried to obtain necessary data about the processes occurring in the flow by analyzing instantaneous velocity measurements carried out by 3D means. A measurement at the points of a low cross-section takes at least 1 minute. During this time all vortex structures, including the largest, occur repeatedly many times and can be studied. The analysis of such measurements was the aim of this article. The process of the generation of vortices at the bottom and their further development, including the conditions of the development of the largest vortices, has been investigated. The results of these investigations are discussed in this article.

4

Principles of systematic analysis in diagnostic's

Vekteris V., Jurevichius M.

Mechanics and Mechanical Engineering

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2002

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Vol. 6, nr 2

77-85

EN

The use of systematic analysis principles for creation of diagnostics measurements systems is described in this paper. The structural scheme of diagnostics measurements is presented. The choose of system elements and their properties are described. A scheme of collection of diagnostics measurements data and statistical analysis is given and stages of the scheme are shortly described. Examples of diagnostics measurements using the laser velocity transducers, accelerometers and non contact induction displacement transducers of mechanical parts of technological machines and data of the statistical analysis is presented too.