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The Measurement of the Adhesion of Glaze Ice

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The Measurement of the Adhesion of Glaze Ice University of Louisville ThinkIR: The University of Louisville's Institutional Repository Electronic Theses and Dissertations 5-2018 The measurement of the adhesion of glaze ice. Andrew Hardesty Work Jr. University of Louisville Follow this and additional works at: https://ir.library.louisville.edu/etd Part of the Other Aerospace Engineering Commons Recommended Citation Work, Andrew Hardesty Jr., "The measurement of the adhesion of glaze ice." (2018). Electronic Theses and Dissertations. Paper 2987. https://doi.org/10.18297/etd/2987 This Doctoral Dissertation is brought to you for free and open access by ThinkIR: The University of Louisville's Institutional Repository. It has been accepted for inclusion in Electronic Theses and Dissertations by an authorized administrator of ThinkIR: The University of Louisville's Institutional Repository. This title appears here courtesy of the author, who has retained all other copyrights. For more information, please contact [email protected]. THE MEASUREMENT OF THE ADHESION OF GLAZE ICE By Andrew Hardesty Work Jr. B.S, University of Louisville 2011 M.Eng., University of Louisville 2012 A Dissertation Submitted to the Faculty of the J.B. Speed School of Engineering of the University of Louisville in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy in Mechanical Engineering Department of Mechanical Engineering University of Louisville Louisville, Kentucky May 2018 THE MEASUREMENT OF THE ADHESION OF GLAZE ICE By Andrew Hardesty Work Jr. B.S, University of Louisville 2011 M.Eng., University of Louisville 2012 A Dissertation Approved on April 19, 2018 By the following Dissertation Committee: __________________________________ Dr. Yongsheng Lian __________________________________ Dr. Geoffrey Cobourn __________________________________ Dr. Stuart Williams ___________________________________ Dr. Gerold Willing ii ACKNOWLEDGEMENTS First and foremost, I would like to thank my advisor Dr. Yongsheng Lian for his support in advising me across two projects during my dissertation, and to Dr. Stuart Williams, Dr. Gerold Willing, and Dr. Geoffrey Cobourn for their guidance and support in serving on my technical committee. I would like to thank the Icing Branch at NASA Glenn for their support of my work by providing countless hours of patient guidance; I would especially like to thank Mario Vargas for his reliable support, guidance, and encouragement. I would also like to thank Peter Struk and Paul Tsao for their support and mentorship. Thanks to Andy Broeren for his help in designing the XT model and for the other guidance he provided, to Chris Porter for his help in the aerodynamic design of the XT model, to Bill Wright for the numerous helpful discussions on LEWICE and past experiments performed in the IRT, and to Tom Ratvasky for his support. Thanks to Mary Wadel, Eric Kreeger, and Mark Potapczuk for their guidance and leadership, and to Justyna Ragiel-Smith for her extensive administrative support. I would also like to thank the RVLT and AATT projects for providing the opportunity to do the work, and to Tony Nerone for his help supporting my work. I would especially like to thank Susan Johnson for her flexibility in consistently going out of her way to support my work and planning ahead to account for the expenses due to my mistakes. My thanks to Andy Gyekenyesi and Jon Salem for their extensive technical guidance and test support, and for catching many of my mistakes. Thanks to Dan Scheiman iii for his generous support in providing test data supporting the XT model, and to John Ramsey for his help in the mechanical analysis of the XT model. I would like to thank Carl Blaser for his advice over the last two years and instrumental help designing and drafting components, as well as his general support in getting the parts produced. Thanks to Tim Heineke for his help in designing and machining components. Thanks to Quentin Schwinn and Jordan Salkin for their imaging support and discussions during piggyback testing. I would especially like to thank the exceptional IRT staff for their generous help during tests, especially Shaun McNea for his support during the first IRT test and making sure the test was successful. I would also like to express my gratitude to my interns for supporting this work and their patience with my novice guidance: Tina Schirmer, Jaime McCarrell, Rebekah Doughlass, Zak Koster, Matthew Gazella, Jodi Turk, and Shawn McTaggart. I would also like to extend my thanks the Ohio Aerospace Institute for their support both in funding several of my students, and for their flexibility in helping collaboration on publications to occur. I would especially to Ann Heyward and Tony Smith. I would like to thank my friends, Seth Tucker, Kyle Hord, Daniel Porter, Russ Prater, Guibo Li, and Yisen Guo, for their support and technical assistance throughout my time at the University of Louisville, for sharing their work with me, and for including me in their projects. None of this would have been possible without the loving patience of my dear wife Mara, who has selflessly sacrificed years of effort to protect my time and keep me sane when I felt like I had lost my path. iv ABSTRACT THE MEASUREMENT OF THE ADHESION OF GLAZE ICE Andrew Work April 19th, 2018 Icing is a lethal and costly aviation hazard affecting aircraft of all sizes ranging from small UAVs to large commercial craft such as the Boeing 787, resulting in hundreds of deaths over the last century and resulting in billions of dollars of economic impact. Three predominant types of icing, namely, airframe icing, engine icing, and rotorcraft icing, dominate aircraft icing research. Each type poses unique challenges. In the case of rotor icing, attention needs to give to the rotating environment with large oscillatory loads and icing conditions. In the case of airframe icing, special attention needs to be paid to a variety of loading cases from the available options for de-icing and anti-icing equipment. In the case of engine icing, the formation mechanism is poorly understood and the structure of the ice needs to be studied in greater detail. Airframe icing requires However, all three share the same fundamental problem that ice sticks to surfaces. How strongly ice adheres to a surface dictates how hard it is to remove. The adhesion strength then regulates the primary threat from icing - the maximum aerodynamic penalty that accretion will have. It also dictates the threat of impingement from shed ice elsewhere on the aircraft, such that a piece of ice from the main rotor could strike the tail rotor on a helicopter, destroying it. v There exist many methods to evaluate the adhesion of ice to a given substrate, the most common being pusher tests and centrifuge tests. These and other methods are problematic in evaluating the adhesive properties of ice to a substrate in aircraft icing conditions; no data in the literature exists that accounts for stress concentrations at the interface and the strain rate at the interface, and no data was found in the literature on the grain structure of impact ice at speeds relevant to aircraft icing. A new method to measure the adhesion of impact ice has been developed based on a lap joint shear test. Lap joint tests are common in adhesion measurements since they produce nearly uniform stress at the interface of interest. In support of this end, a new shear rig and a new wind tunnel model for the Icing Research Tunnel were designed and fabricated. Six nights of testing in the Icing Research Tunnel were conducted to obtain samples, which were later tested in a laboratory environment. The tests were displacement controlled and samples were tested at four crosshead speed rates. The grain structure of the ice was documented using a cross- polarized optical microscope for the first two nights of testing, showing significant differences in the grain structure dependent on velocity and whether the cloud was in the SLD range or not. Correlations with temperature and test section velocity are demonstrated. It was also demonstrated that residual stresses, which are unaccounted for in the literature, play a significant role in the adhesion of impact ice. Options to improve the test methodology further are discussed. Finally, a shedding model predicting the trajectory of ice at a shed event has been developed and validated against test data. This model successfully predicted the front of a multi-break shed event in the Icing Research Tunnel. vi TABLE OF CONTENTS Acknowledgements ............................................................................................................ iii Abstract ................................................................................................................................v List of Tables ..................................................................................................................... ix List of Figures ......................................................................................................................x Introduction ..........................................................................................................................1 The High Cost of Aircraft Icing ...................................................................................... 3 Rotorcraft Icing ............................................................................................................... 6 Aircraft Ice Adhesion and Its Challenges........................................................................ 7 Deicing
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