University of Pennsylvania ScholarlyCommons Publicly Accessible Penn Dissertations 2017 Thermodynamic Analysis For Improving Understanding And Performance Of Hybrid Power Cycles Using Multiple Heat Sources Of Different Temperatures Ting Yue University of Pennsylvania, [email protected] Follow this and additional works at: https://repository.upenn.edu/edissertations Part of the Mechanical Engineering Commons, and the Oil, Gas, and Energy Commons Recommended Citation Yue, Ting, "Thermodynamic Analysis For Improving Understanding And Performance Of Hybrid Power Cycles Using Multiple Heat Sources Of Different Temperatures" (2017). Publicly Accessible Penn Dissertations. 2658. https://repository.upenn.edu/edissertations/2658 This paper is posted at ScholarlyCommons. https://repository.upenn.edu/edissertations/2658 For more information, please contact [email protected]. Thermodynamic Analysis For Improving Understanding And Performance Of Hybrid Power Cycles Using Multiple Heat Sources Of Different Temperatures Abstract Past studies on hybrid power cycles using multiple heat sources of different temperatures focused mainly on case studies and almost no general theory about this type of systems has been developed. This dissertation is a study of their general thermodynamic performance, with comparisons to their corresponding single heat source reference systems. The method used in the dissertation was step-wise: to first analyze the major hybrid power cycles (e.g. Rankine, Brayton, Combined Cycles, and their main variants) thermodynamically, without involving specific operation parameter values, and develop some generalized theory that is at least applicable to each type of system. The second step was to look for commonalities among these theories and develop the sought generalized theory based on these commonalities. A number of simulation case studies were performed to help the understanding and confirm the thermodynamic esults.r Exergo-economic analysis was also performed to complement the thermodynamic analysis with consideration of externalities, and was compared to the conventional economic analysis method. The generalized expressions for the energy/exergy efficiency differences between the hybrid and the corresponding single heat source systems were developed. The results showed that the energy and exergy efficiencies of the hybrid systems are higher than those of their corresponding single heat source reference systems if and only if the energy/exergy conversion efficiency (defined in the dissertation) of the additional heat source (AHS, can be any heat source that has lower temperature) is larger than that of the original heat source. Sensitivity analysis results showed the relations between the temperature and heat addition rate of the AHS and the energy/exergy efficiency of the hybrid systems. Other big advantages of hybrid systems, i.e. the effects on replacement of fossil fuel by renewable, nuclear and waste energy, lower emissions and depletion of fossil fuel, were revealed in the economic analysis, by considering the cost reduction from fuel saving and carbon tax. Simple criteria were developed to help compare the hybrid and reference systems and determine under which conditions the hybrid systems will have better thermodynamic or economic performance than the reference ones. The results and criteria can be used to help design the hybrid systems to achieve higher energy and/or exergy efficiencies and/or lower vle elized electricity cost (LEC) before detailed design or simulation or experiment. So far, 3 archival journal papers and 3 conference papers were published from this dissertation work. Degree Type Dissertation Degree Name Doctor of Philosophy (PhD) Graduate Group Mechanical Engineering & Applied Mechanics First Advisor Noam Lior Keywords Exergo-economic analysis, Multiple heat sources with different temperatures, Power systems simulation, Thermal hybrid power cycles, Thermochemical hybrid power cycles, Thermodynamic analysis Subject Categories Engineering | Mechanical Engineering | Oil, Gas, and Energy This dissertation is available at ScholarlyCommons: https://repository.upenn.edu/edissertations/2658 THERMODYNAMIC ANALYSIS FOR IMPROVING UNDERSTANDING AND PERFORMANCE OF HYBRID POWER CYCLES USING MULTIPLE HEAT SOURCES OF DIFFERENT TEMPERATURES Ting Yue A DISSERTATION in Mechanical Engineering and Applied Mechanics Presented to the Faculties of the University of Pennsylvania in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy 2017 Supervisor of Dissertation _________________________ Dr. Noam Lior Professor, Department of Mechanical Engineering and Applied Mechanics Graduate Group Chairperson _________________________ Dr. Kevin T. Turner, Professor, Mechanical Engineering and Applied Mechanics and Materials Science and Engineering Dissertation Committee Dr. Haim H. Bau, Professor, Committee Chair, Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania Dr. Warren D. Seider, Professor, Department of Chemical and Biomolecular Engineering, University of Pennsylvania Dr. Gerard F. Jones, Professor, Department of Mechanical Engineering, Villanova University THERMODYNAMIC ANALYSIS FOR IMPROVING UNDERSTANDING AND PERFORMANCE OF HYBRID POWER CYCLES USING MULTIPLE HEAT SOURCES OF DIFFERENT TEMPERATURES COPYRIGHT 2017 Ting Yue This work is licensed under the Creative Commons Attribution- NonCommercial-ShareAlike 3.0 License To view a copy of this license, visit https://creativecommons.org/licenses/by-nc-sa/3.0/us/ DEDICATION To my loving parents, especially my Mother for their support and caring, persistently and endlessly iii ACKNOWLEDGMENT First and foremost, I would like to express my sincere gratitude to my beloved academic advisor, Professor Noam Lior. It was a great honor to work under the guidance of Dr. Lior, at one of best universities in the world for the past years. With the help of his decades of experience in the field of power generation and many other related fields, Dr. Lior helped me define the topic, objective and scope of this dissertation and provided much guidance continuously over the years assisting me to overcome the many difficulties that were encountered during my research, with patience and immense knowledge. Dr. Lior also helped me improve my English pronunciation and writing skills, as well as my presentation skills. What’s more, he also taught me about the culture in the US and invited me many times for leisure trips and holiday dinners, making my research life a little easier. There is an old saying in my country as “once a teacher, always a father”, and Dr. Lior is like my father and will always be. Besides my advisor, I would like to thank the rest of my thesis committee: Professor Haim Bau, Professor Warren Seider, and Professor Gerard Jones, for their time in reviewing my proposal and dissertation, and for their insightful comments and encouragement. I would also like to thank all the professors who taught me courses at the University of Pennsylvania, including Dr. Lior, Dr. Lukes, Dr. Ayyaswamy, Dr. Carchidi, Dr. Kumar, Dr. Castañeda, Dr. Kothmann and Dr. Mylovanov. iv Also, thank all the staff in the MEAM office, especially Maryeileen, Peter and Sue, who helped me many kinds of things, which are hard to count. I would like to thank my fellow labmates, especially Yuejun, for the stimulation discussions, for all the work we have been working together, and for all the fun we had in the past years. Also, I would like to thank Professor Zhang Na for teaching me how to use the software and for all other help, such as accompanying my mom when she felt lonely in the US while I was working on my research and could not spend too much time with her. What’s more, I would like to thank the University of Pennsylvania, for admitting me as a PhD student, with the help of Dr. Lior. The university is one of the oldest and best university in the US. It provides modern and comprehensive facilities that made my research and life easier. To name a few, there are numerous food trucks all around the campus, providing cheap and tasty foods from all over the world. It also provides several modern playgrounds so that I can play soccer in the weekend for fun and to keep healthy. One of the playgrounds is even covered with an air tent in the winter so that people can play in there even there is heavy snow outside. Besides the infrastructures, the university is embedded with its unique culture, influencing all its students. For the past many years, I not only studied here but also lived here. This was a priceless experience for me and will surely positively influence my future life. I am really proud of being about to graduate as a PhD student from Penn and hope that Penn will be proud of me as one of her students in the future. v Last but not the least, I would like express my earnest appreciations to my parents. This dissertation is dedicated to them. Without their support, I could not have finished this dissertation. Their support is unconditional and persistent. I will do my best to pay back their love after graduation and make them happy. Ting Yue Philadelphia, PA vi ABSTRACT THERMODYNAMIC ANALYSIS FOR IMPROVING UNDERSTANDING AND PERFORMANCE OF HYBRID POWER CYCLES USING MULTIPLE HEAT SOURCES OF DIFFERENT TEMPERATURES Ting Yue Dr. Noam Lior Past studies on hybrid power cycles using multiple heat sources of different temperatures focused mainly on case studies and almost no general theory about this type of systems has been developed. This