An exploration of the IGA method for efficient reservoir simulation

Novel numerical methods present exciting opportunities to improve the efficiency of reservoir simulators. Because potentially significant gains to computational speed and accuracy may be obtained, it is worthwhile explore alternative computational algorithms for both general and case-by-case application to the discretization of the equations of porous media flow, fluid-structure interaction, and/or production. In the present work, the fairly new concept of isogeometric analysis (IGA) is evaluated for its suitability to reservoir simulation via direct comparison with the industry standard finite difference (FD) method and 1st order standard finite element method (SFEM). To this end, two main studies are carried out to observe IGA’s performance with regards to geometrical modeling and ability to capture steep saturation fronts. The first study explores IGA’s ability to model complex reservoir geometries, observing L2 error convergence rates under a variety of refinement schemes. The numerical experimental setup includes an 'S' shaped line sink of varying curvature from which water is produced in a 2D homogenous domain. The accompanying study simplifies the domain to 1D, but adds in multiphase physics that traditionally introduce difficulties associated with modeling of a moving saturation front. Results overall demonstrate promise for the IGA method to be a particularly effective tool in handling geometrically difficult features while also managing typically challenging numerical phenomena.Petroleum and Geosystems Engineerin

A computer-aided simulation tool based on Petri nets for the design and analysis of FMSs

Discrete-event simulation has been recognized as an invaluable tool in analyzing and designing FMSs. In this dissertation, a computer-aided simulation tool based on Petri nets is presented to facilitate simulation projects in the manufacturing area. For modeling and simulation of FMSs, Conserved nets which are a subclass of Petri nets are proposed and implemented. The structural characteristics and liveness conditions of Conserved nets are investigated. While hardware components are modeled by hierarchically-classified Petri net objects, high-level, real-time control systems in FMSs are separately modeled and integrated with a Petri net model to resolve conflicts occurring in Petri net execution. The structure of the Petri net-based simulation tool is presented. Also, the use of the simulation tool is illustrated with several case studies including performance comparison of push- and pull-based AGV dispatching rules in an FMS. Finally, strengths and weaknesses of the developed simulation tool are discussed including areas for future study

Simulation and Analysis of Arterial Traffic Operations Along the U.S. 61 Corridor in Burlington, Iowa, 1998

The Center for Transportation Research and Education (CTRE) used the traffic simulation model CORSIM to access proposed capacity and safety improvement strategies for the U.S. 61 corridor through Burlington, Iowa. The comparison between the base and alternative models allow for evaluation of the traffic flow performance under the existing conditions as well as other design scenarios. The models also provide visualization of performance for interpretation by technical staff, public policy makers, and the public. The objectives of this project are to evaluate the use of traffic simulation models for future use by the Iowa Department of Transportation (DOT) and to develop procedures for employing simulation modeling to conduct the analysis of alternative designs. This report presents both the findings of the U.S. 61 evaluation and an overview of model development procedures. The first part of the report includes the simulation modeling development procedures. The simulation analysis is illustrated through the Burlington U.S. 61 corridor case study application. Part I is not intended to be a user manual but simply introductory guidelines for traffic simulation modeling. Part II of the report evaluates the proposed improvement concepts in a side by side comparison of the base and alternative models

BIM + Sustainability: Case Study on IES VE Building Performance Simulation

The D.Arch project I have chosen is a case study of the IES (Integrated Environmental Solutions Virtual Environment) Software. The objective of this case study is to challenge the software’s modules capabilities i.e. Radiance, Suncast, and Apache SIM, in conjunction with the Revit MEP (Mechanical, Electrical, and Plumbing) Modeling software. Revit MEP is a building information modeling software developed by Autodesk. The other component to the D.Arch Project is an entry into an Architecture Student competition called Leading Edge 2007/2008. Leading Edge Student Competition 2007/2008 is sponsored by UCSB (University of California Santa Barbara). I chose this competition because building performance analysis is a requirement. I will select a base-case building that has satisfactory energy efficiency standards. I will then compare my design to the base case model. I will quantify the comparable results and identify the correlations between design changes and building performance. I will also do a comparative analysis between IES VE and Green Building Studio. Green Building Studio is a free online service-based company. This analysis results will reveal the true value of the latest attempts to curb climate change via technology. Although this part of my D.Arch Project is not a requirement of the competition, I believe that any new data in the comparison between building simulation software’s is valuable to the AEC (Architecture, Engineering, and Construction) community

Multi-domain Modelling in DESTECS and Ptolemy - a Tool Comparison

Developing embedded systems with high performance and safety requirements is notoriously hard. It is not enough to have a thorough understanding of the control algorithms used, but a deep understanding of the monitored and controlled physical environment is required to ensure that performance and safety requirements are met. Various tools deal with modeling such multi-domain systems and provide evaluation through simulation. Two such tools — DESTECS and Ptolemy — are examined and compared in this paper, using a case study of an aircraft fuel system. Usability, quantitative, and qualitative comparison criteria are used to give a thorough analysis of the capabilities of the two tools. The contribution of this paper is a description of pros and cons of each tool, helping future users to choose the right tool that suits their needs

Integrated Modeling System for Water Resources Management of Tarim River Basin

An integrated modeling system has been developed for water resources management of the Tarim River Basin, China. The system coupled remote sensing (RS)/geography information system (GIS) technique with distributed hydrological model to simulate the rainfall runoff, snow melting, and evapotranspiration process of the hydrological cycle. A case study was carried out in the Kaidu watershed. RS/GIS technique was used for effectively accessing, processing, and managing spatial data, such as land use, vegetative cover, soil, topography, precipitation, and evapotranspiration. The model was calibrated and validated against observed discharge for two hydrological stations during the period 1998-2001, and it generally performed well for Nash-Sutcliffe coefficient, water balance coefficient, and correlation coefficient. The Nash-Sutcliffe coefficient was approximately over 0.7 and the water balance error was lower than +/- 5%, indicating reasonable prediction accuracy. A comparison between the conventional and RS-based hydrological models was conducted. Although the two-models exhibit similar performances on runoff and snow melt simulation, the RS-based hydrological model had better performance in the simulation of actual evapotranspiration. Modeling results provide useful decision support for water resources management

A GENERIC BENCHMARK FOR A MINI-SPLIT HEAT PUMP SYSTEM

Heating, Ventilation, and Air Conditioning (HVAC) accounts for half of the building energy consumption in the U.S where Mini-Split Heat Pumps (MSHPs) are an emerging type of HVAC system. Their utilization has greatly increased by 34% from 2009 to 2013 and high potential EER is recognized for MSHPs. However, there is limited research involving MSHPs systems, and there is no generic benchmark for system testing and modeling. The available simulation tools such as VapCyc, GreatLab, and CYCLE_D are either too complicated, difficult to access, or not freely available. Therefore, an accurate and public share generic benchmark is essential and will be researched for researchers and scientists. In this study, the Heat Pump Design Model (HPDM) is utilized to investigate MSHP performance values. There are five different kinds of input parameters necessary for the HPDM, namely a general system description, system refrigerant-side balancing, compressor characteristics which need a compressor scaling method, fin-and-tube heat exchanger parameters, and system operating conditions. Based on systematic inputs of the HPDM, several key outputs can be obtained, including system capacity, power consumption, and mass flow rate. By comparing output values with existing data sets, the capability of a generic model for MSHP can be identified. In order to validate the methodology analyzed above, two kinds of case studies will be presented. In the first study, a comparison of lab data and simulation results is presented, whereas in the second one, a comparison is conducted between manufacturing data and simulation results. By identifying all of the input parameters for the specified unit, which is the LG LA096HV in this study, the HPDM can obtain simulation results immediately. As indicated by simulation results, the HPDM can be a generic benchmark in a certain temperature range with a relative error below 5%. Advisor: Haorong L

A GENERIC BENCHMARK FOR A MINI-SPLIT HEAT PUMP SYSTEM

Heating, Ventilation, and Air Conditioning (HVAC) accounts for half of the building energy consumption in the U.S where Mini-Split Heat Pumps (MSHPs) are an emerging type of HVAC system. Their utilization has greatly increased by 34% from 2009 to 2013 and high potential EER is recognized for MSHPs. However, there is limited research involving MSHPs systems, and there is no generic benchmark for system testing and modeling. The available simulation tools such as VapCyc, GreatLab, and CYCLE_D are either too complicated, difficult to access, or not freely available. Therefore, an accurate and public share generic benchmark is essential and will be researched for researchers and scientists. In this study, the Heat Pump Design Model (HPDM) is utilized to investigate MSHP performance values. There are five different kinds of input parameters necessary for the HPDM, namely a general system description, system refrigerant-side balancing, compressor characteristics which need a compressor scaling method, fin-and-tube heat exchanger parameters, and system operating conditions. Based on systematic inputs of the HPDM, several key outputs can be obtained, including system capacity, power consumption, and mass flow rate. By comparing output values with existing data sets, the capability of a generic model for MSHP can be identified. In order to validate the methodology analyzed above, two kinds of case studies will be presented. In the first study, a comparison of lab data and simulation results is presented, whereas in the second one, a comparison is conducted between manufacturing data and simulation results. By identifying all of the input parameters for the specified unit, which is the LG LA096HV in this study, the HPDM can obtain simulation results immediately. As indicated by simulation results, the HPDM can be a generic benchmark in a certain temperature range with a relative error below 5%. Advisor: Haorong L