DEM-SPH Coupling

The main aim of the project is to enable the efficient simulation of coupled solid-fluid deformation processes. In particular the project is aimed at the understanding of the brittle deformation of rocks in the presence of fluids. To achieve this it is planned to extend an existing DEM simulation software (ESyS-Particle) by adding a particle-based fluid model, i.e. smooth particle hydrodynamics (SPH) to the software. Planned applications of the method are, for example, hydro-fracturing and deformation of porous materials in the presence of pore fluids.

Validation Test - Pure Shear

 Displacement field colored by horitozontal displacement

Boudinage

Evolution of boudinage ( μ = 1 Pas)

εxx is the amount of vertical shortening.                        

Boudinage with different viscosity values at a given state

(εxx  = 0.65, εyy  = 0.43):

Hydrofracturing

 Hydraulic fracturing simulation (µ = 0.5 Pas)

                                     Hydrofracturing – displacement vectors

• Date of Birth: 2. March 1985.

• Birth name: Andrea Póka

• 2009-

                    RWTH Aachen University, Aachen, Germany

                    Structural Geology, Tectonics and Geomechanics, Geological Institute

                    PhD Student

• 2003 –2008.

                    Eötvös Loránd University of Sciences, Institute of Geography and Earth Sciences, Budapest, Hungary

                    Department of Geophysics

                    MSc in Geophysics

• 2005 – 2008.

                    Semmelweis University, Faculty of Physical Education and Sport Sciences, Budapest, Hungary

                    BSc in Rhythmic Gymnastics

• 1997 – 2003.

                    Bolyai János High School, Salgótarján, Hungary

                    High-school graduation

• 2009

                    RWTH-AAchen

                    Resarch Assistant

                    Main activities: Numerical modelling using Decrete Element Method (DEM) and Smoothed Particle Hydrodynamics (SPH)

• 2008 – 2009

                    Odin Petroleum - Bergen , Norway

                    Consultant Geophysicist

                    Main activities: 2D-3D seismic data analysis, well log, rock physics, AVO analysis

Interpretation of seismic attributes for geothermal energy research

Supervisor

• Dr. Laszló Lenkey (Eötvös Lorand University of Science, Budapest, Hungary)
• Balázs Gellért (MOL, Budapest, Hungary)

Hungary is in favorable geothermal position, because the Pannonian Basin has an extensive geothermal system characterized by high geothermal gradient and heat flow.

In the thesis a carbonate reservoir was studied, which is situated in the Triassic basement. The reservoir has favorable parameters, thermal water with the temperature of 140°C was produced from 2900 m depth. Because of the favorable conditions, the first Hungarian geothermal power plant was planned in this area. The observed area is just next to the Periadriatic-Balaton share zone, therefore there are several faults in the area. One of my goals was to map the faults. The other purpose of my research was to define the border of the carbonate reservoir more accurately.

In the research I was studied seismic attributes. Seismic attributes are the results of different mathematical, statistical analysis. The input data are derived from geophysical well logs and 3D seismic volume. In order to follow the faults and the reservoir, the attributes were calculated along the horizon of the top of the Triassic carbonates.

Three new faults (N-S, WNW-ESE and E-W striking) were defined using the seismic attributes.  The N-S and E-W striking faults are the eastern and the southern border of the reservoir. The western-southwestern border is a NW-SE striking fault, defined on seismic sections. There is no information about the northern boundary, because there is not any 3D seismic data available in the northern area. The salinity values of the water produced from the two sides of the faults are different. Therefore, the faults in the southern and the western-southwestern border act as barriers between separated hydrodynamic systems. The limestone and the dolomite parts of the reservior are separated by a WNW-ESE striking fault running across the carbonates, and there is no hydrodynamic connection between the two parts of the reservoir.

As a result, geological models can be refined based on seismic attributes, moreover certain geological features can be defined due to study of seismic attributes. Thus further information is provided for reserves estimation. This can be the continuation of the research.

Earlier Publications

Andrea Póka, Zoltán Komoróczi          Interpretation of heat flow anomalies in Hungary, 39th Young Scientist Meeting Abstract Book,
                                                        Baja (2008)

Zoltán Komoróczi, Andrea Póka           Processing and interpretation of the geothermal database of Hungary, 39th Young Scientist Meeting 
                                                        Abstract Book,Baja (2008)

Andrea Póka                                      The relationship between of the Earthquakes and the rotation of the Earth, Everyone's University, 
                                                        Szeged (2007)

Andrea Póka                                      Earthquakes and the rotation of the Earth: the variation of the Earthbased on rotation and orientation
                                                        parameters based on the database of the IERS. 38th Young Scientist Meeting Abstract Book,
                                                        Bakonybél (2007)

• 39th Young Scientist Meeting, Baja, 2008 - 1st prize
• Republican scholarship, 2007-2008.
• 38th Young Scientist Meeting, Bakonybél, 2007 - Special prize of MOL and Special prize of the
  Geodetic and Geophysical Research Institute of Hungarian Academy of Science
• National Conference of Scientific Student Association, 2007 - 4th prize, honorable mention
• Conference of Scientific Student Association, 2006 - 2nd prize