Global ETD Search

1	ONE-DIMENSIONAL HIGH-FIDELITY AND REDUCED-ORDER MODELS FOR THREE-WAY CATALYTIC CONVERTER Li, Tongrui January 2018 (has links) To improve the performance of the three-way catalytic (TWC) converter, advanced control strategies and onboard diagnostics (OBD) systems are needed. Both rely on a relatively accurate but computationally efficient TWC converter model. This thesis aims to develop a control-oriented model that can be employed to develop the control strategies and OBD systems of the TWC converter. The thesis consists of two parts, i.e., the high-fidelity model development and the model reduction. Firstly, a high-fidelity model is built using the energy and mass conservation principles. In this model, a constant inlet simulation is used to validate the warming-up characteristics, and a driving cycle simulation is used to calibrate the reaction rate parameters. The results of the simulation show that the high-fidelity model has adequate accuracy. Secondly, a reduced-order model is developed based on phase and reaction simplifications of the high-fidelity model. The aim of the development of the reduced-order model is to propose a computationally efficient model for further development of control strategies and state estimators for OBD systems. The accuracy of the reduced-order model is then validated by means of simulations. / Thesis / Master of Science (MSc) Three-way catalytic converter Converter model High-fidelity model Reduced-order model
2	ONE-DIMENSIONAL HIGH-FIDELITY AND REDUCED-ORDER MODELS FOR THREE-WAY CATALYTIC CONVERTER Li, Tongrui January 2018 (has links) To improve the performance of the three-way catalytic (TWC) converter, advanced control strategies and on-board diagnostics (OBD) systems are needed. Both rely on a relatively accurate but computationally efficient TWC converter model. This thesis aims to develop a control-oriented model that can be employed to develop the control strategies and OBD systems of the TWC converter. The thesis consists of two parts, i.e., the high-fidelity model development and the model reduction. Firstly, a high-fidelity model is built using the energy and mass conservation principles. In this model, a constant inlet simulation is used to validate the warming-up characteristics, and a driving cycle simulation is used to calibrate the reaction rate parameters. The results of the simulation show that the high-fidelity model has adequate accuracy. Secondly, a reduced-order model is developed based on phase and reaction simplifications of the high-fidelity model. The aim of the development of the reduced-order model is to propose a computationally efficient model for further development of control strategies and state estimators for OBD systems. The accuracy of the reduced-order model is then validated by means of simulations. / Thesis / Master of Applied Science (MASc) TWC High-fidelity model Reduced-order model Thermal management system Chemical kinetic
3	Systems Modeling of Thermal Management System for Battery Electric Vehicles Parikesit Pandu Dewanatha (20766728) 25 February 2025 (has links) <p dir="ltr">The rise of battery electric vehicles (BEVs) has been driven by global initiatives to reduce carbon emissions and support technological advancements in battery technology. However, heat loads in these vehicles are inherently transient, and traditional thermal management system (TMS) design approaches are not suitable for designing TMS that allow up-front consideration of transient operation. Graph-based modeling has been explored as a tool for modeling dynamic systems, including thermal systems, due to its modularity and suitability for control design and optimization. It has been successfully applied to air-cycle machines and component-level thermal modeling. For BEV applications, there is an opportunity to expand graph-based modeling into system-level TMS modeling. This approach can solve the complexities of the BEV thermal management, especially with the needs of the rapidly evolving automotive industry.</p><p dir="ltr"> In this thesis, I present the modeling of a BEV TMS using a graph-based modeling framework at both the component and cycle levels. By developing a physics-based, reduced-order model, the thermal interactions within individual components and between connected components are analyzed and discussed in detail. Furthermore, I validate the graph-based model against a high-fidelity benchmark model to assess its accuracy and reliability. The validation process involves simulating and analyzing the dynamic state variables and key performance parameters of the TMS, including temperature, pressure, and enthalpy. These metrics are compared to a high-fidelity benchmark model across various operating conditions. The validated framework provides a strong foundation for future advancements in thermal management systems for BEVs.</p> Electric Vehicle Thermal Management System Battery Electric Vehicle System Modeling System Validation Thermodynamics Python Dymola Reduced-Order Model Low-Fidelity Model HVAC Refrigeration Cycle Two-Phase Flow Closed-Loop Analysis Open-Loop Analysis Data Analysis Transient Response Analysis EV Vapor Compression Cycle Cabin Cycle Battery Cycle Electronics Cooling Cycle Graph-Based Model

1

Page generated in 0.0586 seconds