The objective of the research presented in this thesis is to validate the parallel-bonded modeling method in the context of coupled thermo-mechanical simulations. The simulation results were compared with analytical and experimental data, in the attempt to assess the usability of this particular modeling method. Previous studies of numerical approaches that related to the thermal fracturing of hard rock had used continuum-based models with constitutive relations. The simulations in the thesis were conducted using Particle Flow Code (PFC) which was chosen for the research because of its several benefits. The code has unique features such as spontaneous damage development without imposed conditions, and emergent properties such as material heterogeneity, and dynamic behavior giving possibility to monitor synthetic seismic events. The basic code has been available since 1995 and research using the code has produced hundreds of publications. The thermal option for the code is a recent addition and lacked verification, validation and applications. The thesis is the answer for that. In the course of the research work new particle clustering and grouping routines were developed and tested. Three modeling studies were conducted varying from laboratory to field scales. The 2D modeling study of the heated cylinder experiment yielded similar results both in fracture-behavioral and acoustic emission (AE) magnitude ranges when compared with the laboratory data. The 3D cubic numerical specimens, created with breakable particle clusters, were heated, and the induced damage was observed by P wave velocity measurements. The results showed trends comparable to the laboratory data: P wave velocity decreases with rising temperatures of up to 250°C and cluster-boundary cracking occurs, comparable to grain-boundary cracking in the heated rock samples. The large 2D tunnel models captured the phenomena observed in-situ displaying the difference in the damage to the roof and floor regions, respectively. This damage was due to the filling material confinement of about 100 kPa on the tunnel floor. In general, the results of the thermo-mechanical simulations were in accordance with the experimental data. The modeled temperature evolutions during the heating and cooling periods were also in accordance with the experimental and analytical data.

The objective of the research presented in this thesis is to validate the parallel-bonded modeling method in the context of coupled thermo-mechanical simulations. The simulation results were compared with analytical and experimental data, in the attempt to assess the usability of this particular modeling method. Previous studies of numerical approaches that related to the thermal fracturing of hard rock had used continuum-based models with constitutive relations. The simulations in the thesis were conducted using Particle Flow Code (PFC) which was chosen for the research because of its several benefits. The code has unique features such as spontaneous damage development without imposed conditions, and emergent properties such as material heterogeneity, and dynamic behavior giving possibility to monitor synthetic seismic events. The basic code has been available since 1995 and research using the code has produced hundreds of publications. The thermal option for the code is a recent addition and lacked verification, validation and applications. The thesis is the answer for that. In the course of the research work new particle clustering and grouping routines were developed and tested. Three modeling studies were conducted varying from laboratory to field scales. The 2D modeling study of the heated cylinder experiment yielded similar results both in fracture-behavioral and acoustic emission (AE) magnitude ranges when compared with the laboratory data. The 3D cubic numerical specimens, created with breakable particle clusters, were heated, and the induced damage was observed by P wave velocity measurements. The results showed trends comparable to the laboratory data: P wave velocity decreases with rising temperatures of up to 250°C and cluster-boundary cracking occurs, comparable to grain-boundary cracking in the heated rock samples. The large 2D tunnel models captured the phenomena observed in-situ displaying the difference in the damage to the roof and floor regions, respectively. This damage was due to the filling material confinement of about 100 kPa on the tunnel floor. In general, the results of the thermo-mechanical simulations were in accordance with the experimental data. The modeled temperature evolutions during the heating and cooling periods were also in accordance with the experimental and analytical data.

No description available.

Master of Landscape Architecture / Department of Landscape Architecture and Regional and Community Planning / Eric A. Bernard / The Kansas High Plains region is a key global agricultural production center (U.S. G.S, 2009). The High Plains physiography is ideal agricultural production landscape except for the semi-arid climate. Consequently, farmers mine vast groundwater resources from the High Plains Ogallala Aquifer formations to augment precipitation for crop production. Growing global population, current policy and subsidy programs, declining aquifer levels coupled with regional climatic changes call into question both short-term and long-term resilience of this agrarian landscape and food and water security. This project proposes a means to simulate future irrigated agriculture land use and crop cover patterns in the Kansas High Plains Aquifer region based on coupled modeling results from ongoing research at Kansas State University. A Cellular Automata (CA) modeling framework is used to simulate potential land use distribution, based on coupled modeling results from groundwater, economic, and crop models. The CA approach considers existing infrastructure resources, industrial and commercial systems, existing land use patterns, and suitability modeling results for agricultural production. The results of the distribution of irrigated land produced from the CA model provide necessary variable inputs for the next temporal coupled modeling iteration. For example, the groundwater model estimates water availability in saturated thickness and depth to water. The economic model projects which crops will be grown based on water availability and commodity prices at a county scale. The crop model estimates potential yield of a crop under specific soil, climate and growing conditions which further informs the economic model providing an estimate of profit, which informs regional economic and population models. Integrating the CA model into the coupled modeling system provides a key linkage to simulate spatial patterns of irrigated land use and crop type land cover based on coupled model results. Implementing the CA model in GIS offers visualization of coupled model components and results as well as the CA model land use and land cover. The project outcome hopes to afford decision-makers, including farmers, the ability to use the actual landscape data and the developed coupled modeling framework to strategically inform decisions with long-term resiliency.

This thesis describes complex modeling of asynchronous motor by finite element method. Complex modeling concerns to making models based on different physical principles and their connection. Models are made in Ansys program components and their connection is made in program Ansys Workbench. This thesis includes creating electromagnetic model, thermal model, mechanical model and coupled model which connect partial models.