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Mathematical model of groundwater flow in the permo-carniferous region of the Český Brod environs
Brožová, Magda ; Mls, Jiří (advisor) ; Polák, Michal (referee)
The aim of this thesis is an overall assessment of the hydrogeological conditions of the Český Brod Permian Carboniferous and overall the balance of upper groundwater aquifer in the northern part of the Český Brod Permian Carboniferous using a mathematical model. For the realization of the model was used ZABAGED data provided by the Czech Office for Surveying, Mapping and Cadastre, which is located in Prague 8 Kobylsích. The mathematical model was created using computer applications such as FeFlow 5. 2, ArcGIS for Desktop 10. 1 and Surfer 10. 7. 972. The result of this work is to evaluate the overall balance of precipitation, surface water and groundwater in the upper aquifer north of Český Brod Permian Carboniferous, respectively, in the hydrologic basin of the Upper and Middle Elbe, in the hydrological basin fourth Order river Vyrovka (HEIS.VUV.cz). The evaluation was done by comparing the data obtained from the studied opinions and based on data obtained from calculations of the mathematical model. The results of the mathematical model were also compared with the original model hydroizohyps, which was created based on the coordinates of the individual wells in a given area and treble steady groundwater levels, coordinate and treble levels of selected points on each watercourse. Before completing...
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Tidal phenomena in groundwater hydraulics
Ondovčin, Tomáš ; Mls, Jiří (advisor) ; Šembera, Jan (referee) ; Novotný, Oldřich (referee)
Manifestations of the tidal force have been known to humanity since an- tiquity. The oldest extant remarks on the origin of the tidal force are in the Natural History of Pliny the Elder. He also left us remarks on periodic changes of water-level in wells. This phenomenon does not necessarily have to be connected to the proximity of seas. As such, it is a subject of research since the end of 19th century. Exploring the mechanisms with which the tidal force affects the groundwater level requires combining the findings of geology and hydrogeology but also the knowledge of hydraulics and geomechanics of porous media and certain understanding of astronomy. This thesis contribu- tes to the knowledge of the mechanism of tidal oscillations in groundwater measured in a borehole near Teplice nad Metují in Police Basin. It utilizes models based on the knowledge of geological and hydrogeological structure of the surroundings of the borehole. It investigates the relation between the physical properties of porous media and the amplitude and phase of the tidal oscillations and presents solutions of the models.
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Circulation wells and their mathematical modelling
Nedvěd, Jakub ; Mls, Jiří (advisor) ; Šantrůček, Jaromír (referee)
Groundwater is our priceless natural resource and it is our duty to protect it and to take care of its quality. That is the reason why several techniques of pollution removal have been developed; the Groundwater Circulation Well technique (GCW) is one of them. This system enables us to clean contaminated groundwater effectively and in-situ (it means that there is no need to extract groundwater to the surface). This thesis is aimed at collecting and presenting our actual knowledge of the most common GCW systems. In the first part of the thesis the basic kinds of the GCW are introduced and their principles are presented. The remediation mechanisms are further described with respect to the character of the particular contamination. The chemical and biological processes controlling the contaminant degradation are described. Several experiments that were carried out and monitored in order to study the efficiency of GCWs are presented. In the last part of the thesis the mathematical modelling of GCWs is introduced. The partial differential equations governing the processes of flow and mass transport in the well surrounding parts of aquifers are presented and the corresponding initial and boundary conditions are formulated. The obtained numerical results and conclusions of their comparison with measured data are...
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Numerical modeling in groundwater contamination problems
Havlíková, Barbora ; Datel, Josef (advisor) ; Mls, Jiří (referee)
This bachelor thesis deals with numerical modelling of groundwater flow and contaminant transport. This thesis consists of two parts. In the first part are briefly described and compared basic methods, which are used for solving problems of groundwater flow and substance transport. Further more are set up initial and boundary conditions, which are an essential part of the compilation model. The second part deals with models from location Bzenec, where was the leakage of chlorinated aliphatic hydrocarbons. Models were created in purpose to describe the extent of contamination and spreading of contaminants and also to predict the further development of the pollution.
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Hydraulic fracturing
Mazáček, Michal ; Mls, Jiří (advisor) ; Fischer, Tomáš (referee)
This bachelor thesis deals with the process of hydraulic fracturing. Hydraulic fracturing (also called fracking or fracjob) is a method used for the stimulation of the oil or gas reservoirs. The point of the method is to inject the liquid under high pressure into the formation. The injection cause widening of existing fractures or making new ones. The goal of this thesis was to describe basic knowledge that are necessary to successful treatment. There were basics of rock mechanics described such as linear elasticity, plasticity etc. The main chapter describes the parameters of the fracture such as fracture wide, fracture height, fluid flow and fluid loss. Furthermore, the kinds of liquids were discussed in one chapter. In the end, the fracturation which had been done in Texas(USA) were shown and the spreading of the fractures were discussed.
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Numerical modelling of water content and pressure head relations of a capillary barrier
Trpkošová, Dagmar ; Mls, Jiří (advisor) ; Wohnlich, Stefan (referee) ; Schoenherr, Jürgen (referee)
1 Charles University in Prague Faculty of Science Institute of Hydrogeology, Engineering Geology and Applied Geophysics Numerical modelling of pressure and runoff conditions of a capillary barrier Summary of PhD Thesis Dagmar Trpkošová May 2010 2 Abstract The closing of landfills is a very topical issue in Europe, with many European countries already scheduling the end of waste disposal at these sites (Biele, 2007). A capillary barrier is one option for surface closure of landfills. For covering landfills of municipal waste, European regulations require that surface sealing for class 2 waste be made up of two independent components. In most cases, this is satisfied by the combination of an artificial and a mineral sealing. The next development stage of the capillary barrier is the combined capillary barrier (Wohnlich, 2006a), intended as an alternative to conventional combined sealing. Prof. Dr. Stefan Wohnlich and his team at Ruhr-University Bochum undertook a series of laboratory experiments simulating capillary barriers in a tipping trough. The German association LAGA was made aware of the conducted research. The research should be focused on the combined capillary barrier and should particularly answer questions concerning the pressure and runoff condition of a combined capillary barrier. During my...
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Determination of hydraulic characteristcs of clay suspensions
Petrová, Markéta ; Mls, Jiří (advisor) ; Handová, Zdena (referee)
This thesis is focused on determining the hydromechanical characteristics of clay suspensions, permeability and compressibility, where is the effective stress, the concentration of suspension and is the permeability. Because the compressibility or permeability can't be measured directly, I use Darcian mechanics of two-phase systems to compute the characteristics I wanted from a well- measurable quantities, measured in appropriate experiments. Work has been solved with the support of the project : Hydromechanical characteristics of clay suspensions. The first part deals with a mineralogical characteristics fylosilicates, characterization of kaolin deposits in the Bohemian Massif, physical chemistry of colloidal systems, electric double layers and electro kinetic potential. Experimental section follows later, which proceed from the assumption that the same concentration of kaolin suspension and an identical colloidal state, exposed to the same pressure-temperature conditions, exhibit the same values of hydro mechanical characteristics such as their evolution in time can be described as a continuous function. As the model, I chose the coagulated kaolin suspension. Coagulation are achieved by adding weight percent of solids . Suspension settles in a vertical cylinder of high with an inner diameter of , which...
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Adsorption of radionuclides in granite pores and micropores
Šindelář, Jakub ; Mls, Jiří (advisor) ; Šantrůček, Jaromír (referee)
Adsorption of radionuclides in granite pores and micropores ABSTRACT This graduation thesis deals with laboratory determination of adsorption isotherms parameters. Granite from the central moldanubian pluton, site Panské Dubenky, Czech Republic, was chosen to the experiment. The place is one of the candidate sites to build a deep nuclear waste disposal. A batch experiment was performed in two modes, differing in the way of addition of radioactive nuclide 90 Sr. From this experiment, distribution coefficients for a linear isotherm or parameters for Langmuir isotherm were obtained. Beside this, a through-diffusion experiment was performed. The objective of this experiment was to identify whether some of the radionuclides used (137 Cs, 90 Sr, 125 I) is able to penetrate through the pores of a granite slice barrier between two solutions of different concentrations. During the period of the experiment no radionuclide was detected reliably.
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