National Repository of Grey Literature 81 records found  1 - 10nextend  jump to record: Search took 0.00 seconds. 
Effect of pipe inclination on flow behaviour of fine-grained settling slurry
Vlasák, Pavel ; Chára, Zdeněk ; Matoušek, Václav ; Konfršt, Jiří ; Kesely, Mikoláš
The effect of flow parameters of fine-grained settling slurry on the pressure drop-velocity relationship, deposition limit velocity and local concentration distribution was studied in an experimental pipe loop of inner diameter D = 100 mm with inclinable pipe sections for pipe inclination ranging from – 45° to +45°. The slurry consisted from water and narrow particle size distribution glass beads of mean diameter d50 = 0.18 mm. The concentration distribution was studied with application of a gamma-ray densitometry. The deposition velocity was defined as the flow velocity at which stationary deposit started to be formed at the pipe invert. The study revealed the stratified flow pattern of the studied slurry in inclined pipe sections, for slurry velocities below to the deposition limit sliding or stationary bed were created in ascending pipe sections. For low pipe inclination (􀄮 < ± 25°) the effect of inclination on local concentration distribution was not significant. Mean transport concentration for descending flow was lower than that for the ascending flow Deposition limit in inclined pipe was slightly lower than that in horizontal pipe. Frictional pressure drops in ascending pipe were higher than that in descending pipe, the difference decreased with increasing velocity and inclination.
Settling slurry flow near deposition velocity in inclined pipe of negative slope
Kesely, Mikoláš ; Matoušek, Václav ; Vlasák, Pavel
Pipe flow of sand-water slurry (settling slurry) is sensitive to pipe inclination. The effect of the angle to which the partially stratified flow is inclined from the horizontal has been subject to investigation in numerous studies. However, almost all of them focus on ascending flows, i.e. flows inclined to positive angles of inclination. It is well known that settling slurry flows inclined to negative slopes (descending flows) differ from those inclined to positive slopes, particularly at velocities near the deposition limit. The deposition limit velocity is the flow velocity at which stationary deposit starts to be formed at the bottom of the pipe. We investigate the effect of the negative slope on pipe flow near deposition limit velocity in the broad range of inclination angles. Besides the deposition limit, we focus on the distribution of solids across the pipe cross section. We combine experimental approach with mathematical modelling. Our new experiments with medium-to-coarse sand (mass-medium grain size 0.87 mm) in a 100-mm pipe inclined from 0 to -45 degree provide suitable data for a validation of predictions of our layered model for partially stratified flows in inclined pipes.
Origin and initial development of the interwar resort Pikovice
Keprta, Štěpán ; Matoušek, Václav (advisor) ; Sekyrková, Milada (referee)
This thesis deals with recreational activities at the end of 19th and beginning of 20th century. Theoretical part focuses on society that is going through significant changes in the process of industrialization. The middle class of society is trying to demonstrate their social status by leisure time activities. Many people are becoming members of sports and touristic clubs. They also take interest in their local environment and cultural events generally. These activities are also frequently followed by raising nationalism. Important chapter is devoted to landscape ecology. At the end of the theoretical part there's also analysis of historical novel mentioning this topic. The empirical research describes origins and development of Pikovice summer resort which served to Prague citizens mainly. First there's a description of environment and geography of the region followed by local history. The key chapter is explaining in detail the development of private recreational houses and then it analyzes social status of their owners and of the construction companies that were involved. Also a discussion is given about the changes in landscape caused by extended construction works. Key words: Pikovice, Recreation, Villas, Cabins, Tramping, Industrialization, Countryside
Rakovnik 1620 Battlefield (Contribution to the Metal-Detector Prospecting of the Early Modern Battlefields)
Šámal, Zdeněk ; Matoušek, Václav (advisor) ; Vařeka, Pavel (referee)
In 2010 the Museum of T. G. M Rakovník began an archaeological survey on a large scaled area, where from 27th of October till the 5th of November 1620, military clashes between the Estates army and the allied forces of the Roman Emperor with the Catholic League took place, just before the battle on Bílá hora. The research, originally associated with the preparation of regional exhibition, grew over the years into a unique project in the field of post-Medieval military activities archaeology. It has two major pillars. First was the field survey, which also covers air prospection, which identifies remains and also offers a geodetic survey of the debris field fortifications, which the army had built. The second is the use of detector prospecting in connection with the GPS data and its subsequent projection into maps. In the past twenty years, metal detectors became a sensitive problem not only in the Czech archaeology sphere. But they are also a useful and efective tool. Experience from abroad shows that an archaeological research of battlefields can't be done without detector prospecting. So far the detector research of the Rakovník battlefield has lasted four seasons (2010-2014) and its main focus has been on finding and localising the lead bullets for firearms used in The Thirty Year War. It was...
The Transformation of Šumava Mountains at the time of industrialization: Forgotten Traces of Woodworkers
Blažková, Tereza ; Matoušek, Václav (advisor) ; Semotanová, Eva (referee) ; Krajíc, Rudolf (referee)
The aim of the thesis is to show the changes and the development of the landscape and the settlement of the region of central Šumava mountains due to industrialization in the 19th century. The thesis is based theoretically and methodologically in the field of anthropology of landscape and industrial archeology. It combines archive written and cartographic sources with non-destructive field research of anthropogenic relics. The industrialization of the area of interest meant the woodworking expansion that was caused by the lack of firewood in Prague and its surroundings and was realized as a business plan by the noble Schwarzenberg family. Schwarzenberg forest exploatation and timber floating system for firewood transport have brought significant landscape changes to hitherto almost untouched mountaneous forested areas. The field research has identified elements of the floating timber system, such as water reservoirs, watercourse troughs or the Vchynicko-Tetovský floating canal, as well as traces of both, permanent and seasonal settlement of woodcutters. The work divides the area into four zones, depending on how they were used, settled and transformed during the 19th century. The greatest attention is devoted to zone no. I, the remote forest area, which has become a major resource area for the Schwarzenberg...
Experimental investigation of settling slurry flow in inclined pipe sections
Vlasák, Pavel ; Chára, Zdeněk ; Matoušek, Václav ; Kesely, Mikoláš ; Konfršt, Jiří
Narrow particle size distribution glass beads-water slurry flow in the pipe sections of different inclination were investigated on an experimental pipe loop of inner diameter D = 100 mm. The study refers to the effect of pipe inclination and slurry velicity on local concentration distribution, pressure drop-velocity relationship, and deposition limit. The study revealed that the glass beads-water mixtures in the inclined pipe sections were significantly stratified: the solid particles moved principally close to the pipe invert, and for flow velocities close to the deposition limit sliding bed or stationary deposit is created even in inclined pipe sections.
Summer resorts Karlštejn and Srbsko. Contribution to study of transformation suburban landscape during the period of industrialization
Čechová, Tereza ; Matoušek, Václav (advisor) ; Sekyrková, Milada (referee)
This diploma thesis is about recreational activities of citizens of Prague in the period from the second half of 19th century through the second half of 20th century. It focuses on the era of industrialization, in which the suburban landscape underwent many changes, mainly thanks to new development of the city. This thesis is divided into theoretical and empirical part. The theoretical part is dedicated to the terms of industrialization and industrial revolution. It moreover deals with stratification of the society, focusing on the middle class, and describes recreational activities in different resorts. From the recreational activities, tramping and settlement establishing are specifically described. The empirical part is dedicated to two recreational resorts, Karlštejn and Srbsko, which are one train station apart from each other. In each case there is a description of the location of the resort. The description of the original inhabitants, recreational objects, current inhabitants and their important buildings and the cottage areas is following. One chapter is about a particular tramping settlement in Srbsko called "Valley of Dread". The paper analyzes what builders were chosen by the holiday-makers and also the social characteristics of the holiday-makers. An important chapter is about...
Summer resort Senohraby. Contribution to study of transformation suburban landscape during the period od industrialization
Chaloupková, Romana ; Matoušek, Václav (advisor) ; Pauknerová, Karolína (referee)
This diploma thesis deals with the recreational activities of the inhabitants of Prague and their influence on the transformation of the suburban landscape at the time of industrialization. It characterizes the time period from the mid-19th century to the 40s of the 20th century. The thesis is divided into the theoretical and empirical part. In the theoretical part, it deals with the period of industrialization and, in connection with it, also with the industrial revolution. Further, the work is devoted to concrete manifestations of mass and individual recreation in the 19th century and consequently demographic growth of the inhabitants on the Czech territory, development of the middle class, establishment of the resort and the origin and importance of the Beautification Committee. The theoretical part ends with the characteristics of summer flats and other manifestations of individual and mass recreation until the middle of the 20th century. The empirical part deals with the characteristic, natural, geomorphological and historical development of Senohraby village. The main part of the work focuses on the development of recreational buildings from the 1918s to the 40s of the 20th century on the basis of archive materials. In the next chapters, the issue of summer flats, summer guests and their...
Deposition limit velocity: effect of particle size distribution
Matoušek, Václav ; Visintainer, R. ; Furlan, J. ; McCall II, G. ; Sellgren, A.
Industrial settling slurries often consist of particles of very different sizes - the particle size distribution may cover sizes which differ with two orders of magnitude. A broad particle size distribution affects parameters of slurry flow including deposition limit velocity. We present experimental results of the deposition limit velocity collected during a comprehensive experimental campaign testing slurry flows composed of solids of different fractions in the GIW Hydraulic Laboratory in 2016. Four narrow graded fractions (carrier fluid, pseudo-homogeneous, heterogeneous, and stratified) were tested in permutations from the individual components to the complete mixture at various concentrations. The primary experiments were carried out in a 203-mm pipe, and selected corresponding experiments were repeated in a 103-mm pipe. The experimental results show that interactions among components affect the resulting deposition limit velocity in flows of broadly graded settling slurries. The effect of particle size distribution on the deposition limit velocity is not benign. The deposit velocity is not necessarily lower in a flow of slurry composed of four components than in slurry flow of one component with the highest deposit velocity from the four components. We discuss possible modifications of a deposit velocity predictive model in order to take effects of a broad particle size distribution into account.

National Repository of Grey Literature : 81 records found   1 - 10nextend  jump to record:
See also: similar author names
1 Matoušek, V.
1 Matoušek, Vladimír
2 Matoušek, Vladimír,
6 Matoušek, Vojtěch
3 Matoušek, Vít
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