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You searched for +publisher:"Clemson University" +contributor:("Dr. Mark Hoffman, Co-Chair"). Showing records 1 – 2 of 2 total matches.

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Clemson University

1. O'Donnell, Ryan. Experimental and Analytical Techniques for Evaluating the Impact of Thermal Barrier Coatings on Low Temperature Combustion.

Degree: PhD, Automotive Engineering, 2018, Clemson University

Homogeneous Charge Compression Ignition (HCCI), exhibits many fundamentally attractive thermodynamic characteristics. These traits, along with lean charge and low combustion temperatures, generally act to increase thermal efficiency relative to competing spark and/or compression ignition strategies. However, HCCI's extreme sensitivity to in-cylinder thermal conditions, place limits on practical implementation. Thus, at low temperatures, combustion remains incomplete limiting cycle efficiency while increasing emissions. In contrast, the introduction of thermal barrier coatings (TBCs) to in-cylinder surfaces has been shown to fundamentally alter gas-wall interactions. The work in this dissertation explores HCCI/TBC synergies. Both experimental and analytical pathways are explored, attempting to illuminate the impact(s) of coatings on engine heat transfer and combustion metrics. Efforts to correlate TBC thermophysical properties and surface phenomena with HCCI performance and emissions are also explored. Finally, methods are proposed to evaluate the TBC-gas interaction as it relates to thermal stratification of the in-cylinder charge. The present work seeks to identify, and eventually quantify HCCI/TBC synergies. A specific research effort is developed, attempting to illuminate the impact(s) of TBCs on fundamental HCCI combustion metrics. Efforts to correlate TBC thermophysical properties and surface phenomena with HCCI performance and emissions are also proposed. Analysis is enabled through complimentary analytic and experimental pathways - which includes specialized solution methodology and experimental hardware. Combined, these tools enable a more complete qualitative assessment of thermal barrier coating's impact on engine performance and emissions metrics, heat loss at the wall, and ultimately thermal stratification of the in-cylinder temperature field. Advisors/Committee Members: Dr. Zoran Filipi, Committee Chair, Dr. Mark Hoffman, Co-Chair, Dr. Richard Miller, Dr. Robert Prucka.

Subjects/Keywords: Combustion Efficiency; HCCI; Heat Transfer; Low Temperature Combustion; Thermal Barriers; Thermal Efficiency

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

O'Donnell, R. (2018). Experimental and Analytical Techniques for Evaluating the Impact of Thermal Barrier Coatings on Low Temperature Combustion. (Doctoral Dissertation). Clemson University. Retrieved from https://tigerprints.clemson.edu/all_dissertations/2200

Chicago Manual of Style (16th Edition):

O'Donnell, Ryan. “Experimental and Analytical Techniques for Evaluating the Impact of Thermal Barrier Coatings on Low Temperature Combustion.” 2018. Doctoral Dissertation, Clemson University. Accessed January 25, 2021. https://tigerprints.clemson.edu/all_dissertations/2200.

MLA Handbook (7th Edition):

O'Donnell, Ryan. “Experimental and Analytical Techniques for Evaluating the Impact of Thermal Barrier Coatings on Low Temperature Combustion.” 2018. Web. 25 Jan 2021.

Vancouver:

O'Donnell R. Experimental and Analytical Techniques for Evaluating the Impact of Thermal Barrier Coatings on Low Temperature Combustion. [Internet] [Doctoral dissertation]. Clemson University; 2018. [cited 2021 Jan 25]. Available from: https://tigerprints.clemson.edu/all_dissertations/2200.

Council of Science Editors:

O'Donnell R. Experimental and Analytical Techniques for Evaluating the Impact of Thermal Barrier Coatings on Low Temperature Combustion. [Doctoral Dissertation]. Clemson University; 2018. Available from: https://tigerprints.clemson.edu/all_dissertations/2200


Clemson University

2. Xu, Bin. Plant Modeling, Model Reduction and Power Optimization for an Organic Rankine Cycle Waste Heat Recovery System in Heavy Duty Diesel Engine Applications.

Degree: PhD, Automotive Engineering, 2017, Clemson University

With pressure from strict emission and fuel consumption regulations, researchers are searching for improved internal combustion engine performance. Especially for the heavy-duty vehicles, which takes up 7% of the total vehicle volume while consume around 30% of transportation energy in US. Around 40-60% of energy is wasted as heat in heavy-duty diesel (HDD) vehicles in different engine operating conditions, which mainly includes the waste heat in exhaust gas, exhaust gas recirculation (EGR) circuit, and engine coolant. Waste heat recovery (WHR) techniques are potential to achieve the fuel economy and emission reduction goals. Among the available WHR techniques, organic Rankine cycle (ORC) is preferred by many researchers for its mature technologies and high efficiency. The aim of this dissertation is to analyze the power of HDD vehicle by: (i) building a high fidelity, physics-based ORC-WHR dynamic system plant model, (ii) building a reduced order model framework, and (iii) conducting the power analysis based on the developed plant and reduced models. The dynamic system plant model is built, which includes heat exchangers, a turbine expander, pumps, control valves, compressible volumes, junctions and a reservoir. Components are modelled and calibrated individually. Subsequently, the component models are integrated into an entire ORC-WHR system model. The entire ORC-WHR system model is validated over transient engine conditions. Actuator sensitivity study is conducted for the ORC-WHR power generation analysis using the ORC-WHR plant model. Besides the ORC-WHR plant model, a reduced order model framework is developed utilizing Proper Orthogonal Decomposition (POD) and Galerkin projection approaches. The POD-Galerkin reduced order model framework inherits the system physics from the high fidelity, physics-based ORC-WHR plant model. POD Galerkin reduced order models are compared with three existing models (finite volume model, moving boundary model and 0D lumped model) and show their advantages over the existing models in terms of accuracy or computation cost. In addition, identification method is applied to the low order POD Galerkin reduced order model to increase the accuracy. Given the validated ORC-WHR plant model and POD Galerkin reduced order model framework, the ORC-WHR system power analysis is conducted. Steady state power analysis is conducted over two quasi-steady driving cycles using the ORC-WHR plant model. An engine model is developed to predict the exhaust conditions in transient engine operating conditions. Transient power analysis is conducted with ORC-WHR plant model and engine model co-simulation by optimizing three vapor temperature reference trajectories. Finally, dynamic programming (DP) is implemented with the POD-Galerkin reduced order model to generate ORC-WHR power benchmark in a driving cycle, which can give the guidance on the ORC power optimization and evaluate the controller performance. Advisors/Committee Members: Dr. Simona Onori, Committee Chair, Dr. Zoran Filipi, Co-Chair, Dr. Mark Hoffman, Co-Chair, Dr. Beshah Ayalew.

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Xu, B. (2017). Plant Modeling, Model Reduction and Power Optimization for an Organic Rankine Cycle Waste Heat Recovery System in Heavy Duty Diesel Engine Applications. (Doctoral Dissertation). Clemson University. Retrieved from https://tigerprints.clemson.edu/all_dissertations/2040

Chicago Manual of Style (16th Edition):

Xu, Bin. “Plant Modeling, Model Reduction and Power Optimization for an Organic Rankine Cycle Waste Heat Recovery System in Heavy Duty Diesel Engine Applications.” 2017. Doctoral Dissertation, Clemson University. Accessed January 25, 2021. https://tigerprints.clemson.edu/all_dissertations/2040.

MLA Handbook (7th Edition):

Xu, Bin. “Plant Modeling, Model Reduction and Power Optimization for an Organic Rankine Cycle Waste Heat Recovery System in Heavy Duty Diesel Engine Applications.” 2017. Web. 25 Jan 2021.

Vancouver:

Xu B. Plant Modeling, Model Reduction and Power Optimization for an Organic Rankine Cycle Waste Heat Recovery System in Heavy Duty Diesel Engine Applications. [Internet] [Doctoral dissertation]. Clemson University; 2017. [cited 2021 Jan 25]. Available from: https://tigerprints.clemson.edu/all_dissertations/2040.

Council of Science Editors:

Xu B. Plant Modeling, Model Reduction and Power Optimization for an Organic Rankine Cycle Waste Heat Recovery System in Heavy Duty Diesel Engine Applications. [Doctoral Dissertation]. Clemson University; 2017. Available from: https://tigerprints.clemson.edu/all_dissertations/2040

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