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Investigation of Various Novel Air-Breathing Propulsion Systems

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Investigation of Various Novel Air-Breathing Propulsion Systems Investigation of Various Novel Air-Breathing Propulsion Systems A thesis submitted to the Graduate School of the University of Cincinnati in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE in the Department of Aerospace Engineering & Engineering Mechanics of the College of Engineering and Applied Science 2016 by Jarred M. Wilhite B.S. Aerospace Engineering & Engineering Mechanics University of Cincinnati 2016 Committee Chair: Dr. Ephraim Gutmark Committee Members: Dr. Paul Orkwis & Dr. Mark Turner Abstract The current research investigates the operation and performance of various air-breathing propulsion systems, which are capable of utilizing different types of fuel. This study first focuses on a modular RDE configuration, which was mainly studied to determine which conditions yield stable, continuous rotating detonation for an ethylene-air mixture. The performance of this RDE was analyzed by studying various parameters such as mass flow rate, equivalence ratios, wave speed and cell size. For relatively low mass flow rates near stoichiometric conditions, a rotating detonation wave is observed for an ethylene-RDE, but at speeds less than an ideal detonation wave. The current research also involves investigating the newly designed, Twin Oxidizer Injection Capable (TOXIC) RDE. Mixtures of hydrogen and air were utilized for this configuration, resulting in sustained rotating detonation for various mass flow rates and equivalence ratios. A thrust stand was also developed to observe and further measure the performance of the TOXIC RDE. Further analysis was conducted to accurately model and simulate the response of thrust stand during operation of the RDE. Also included in this research are findings and analysis of a propulsion system capable of operating on the Inverse Brayton Cycle. The feasibility of this novel concept was validated in a previous study to be sufficient for small-scale propulsion systems, namely UAV applications. This type of propulsion system consists of a reorganization of traditional gas turbine engine components, which incorporates expansion before compression. This cycle also requires a heat exchanger to reduce the temperature of the flow entering the compressor downstream. While adding a heat exchanger improves the efficiency of the cycle, it also increases the engine weight, resulting in less endurance for the aircraft. Therefore, this study focuses on the selection and development of a new heat exchanger design that is lightweight, and is capable of transferring significant amounts of heat and improving the efficiency and performance of the propulsion system. ii iii Acknowledgements First and foremost, I would like to acknowledge and thank Dr. Ephraim Gutmark. He has been an excellent advisor who has provided me with meaningful and interesting research opportunities, which have funded me throughout my time as a graduate student. I would also like to thank Dr. Paul Orkwis and Dr. Mark Turner for serving on my thesis committee. Each of my committee members are great professors. I really enjoyed their classes, and was able to learn a lot from both of them. I would like to acknowledge Andrew St. George and Robbie Driscoll, who introduced me to detonation research, and gave me helpful advice to effectively conduct research and write research papers. I would also like to thank my fellow detonation research team members, including Vijay Anand, William Stoddard, Ethan Knight, and Justas Jodele for their encouragement, great advice and willingness to help me complete my experiments. I also thank Kranthi Yellugari for his assistance and willingness to work with me on heat exchanger design and analysis. I am very grateful for the help and assistance from Ron Hudepohl whose guidance in the machine shop was very essential in machining parts for the thrust stand and RDE. I also appreciate the technical knowledge and support that I received from Mark Grooms and Curt Fox in the Gas Dynamics & Propulsion Laboratory. I would also like to thank my fellow lab mates for their support and friendship throughout my time in graduate school. I would also like to acknowledge Dr. Dunn, Mr. Simonson, Ms. Christine Johnson, Dr. Brandi Elliott and Dr. Eric Abercrumbie for their emotional support, encouragement and invaluable mentorship since my freshman year at the University of Cincinnati. Lastly, I dedicate this thesis to my parents, Charles & Myrita, my brother, Justin, and the rest of my family for being an extremely positive influence in my life, and their genuine interest and constant encouragement to succeed and excel in all of my endeavors, especially academics. I also dedicate this to the love of my life, Devaki, who motivates and inspires me to pursue my dreams. iv Table of Contents Abstract ......................................................................................................................................................................................... ii Acknowledgements .................................................................................................................................................................. iv Table of Contents ....................................................................................................................................................................... v List of Figures........................................................................................................................................................................... vii List of Tables ............................................................................................................................................................................... x List of Symbols ......................................................................................................................................................................... xi Chapter 1: Introduction ............................................................................................................................................................ 1 1.1 Rotating Detonation Engine (RDE) ...................................................................................................................... 1 1.2 One-Dimensional Analysis ...................................................................................................................................... 3 a) Detonation Theory ................................................................................................................................................. 3 b) Hugoniot Curve ...................................................................................................................................................... 5 c) ZND Theory ............................................................................................................................................................ 8 1.3 Three-Dimensional Detonation Structure ........................................................................................................... 9 1.4 Thermodynamic Cycle Analysis .......................................................................................................................... 12 a) The Detonation Cycle ......................................................................................................................................... 13 b) The Inverse Brayton Cycle ............................................................................................................................... 15 1.5 RDE Literature ........................................................................................................................................................... 17 1.6 Thrust in Detonation Engines................................................................................................................................ 19 1.7 Research Objectives ................................................................................................................................................. 23 a) Rotating Detonation Engine ............................................................................................................................. 23 b) Inverse Brayton Cycle Propulsion System .................................................................................................. 24 Chapter 2: Experimental Methodology ............................................................................................................................ 26 2.1 University of Cincinnati Detonation Test Facility ......................................................................................... 26 a) Test Bunker & Safety Features ....................................................................................................................... 26 b) Low Mass Flow System .................................................................................................................................... 28 c) High Mass Flow System .................................................................................................................................... 31 d) Data Acquisition (DAQ) and Control System ............................................................................................ 33 2.2 Experimental Setup .................................................................................................................................................. 34 v a) Instrumentation ....................................................................................................................................................
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