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Design and Testing of Experimental Langmuir Turbulence Facilities University of South Florida Scholar Commons Graduate Theses and Dissertations Graduate School June 2019 Design and Testing of Experimental Langmuir Turbulence Facilities Zongze Li University of South Florida, [email protected] Follow this and additional works at: https://scholarcommons.usf.edu/etd Part of the Mechanical Engineering Commons Scholar Commons Citation Li, Zongze, "Design and Testing of Experimental Langmuir Turbulence Facilities" (2019). Graduate Theses and Dissertations. https://scholarcommons.usf.edu/etd/7845 This Thesis is brought to you for free and open access by the Graduate School at Scholar Commons. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Scholar Commons. For more information, please contact [email protected]. Design and Testing of Experimental Langmuir Turbulence Facilities by Zongze Li A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Mechanical Engineering Department of Mechanical Engineering College of Engineering University of South Florida Major Professor: David Murphy, Ph.D. Andres E. Tejada-Martinez, Ph.D. Rasim Guldiken, Ph.D. Date of Approval: June 11, 2019 Keywords: ANSYS Simulation, Fluid Mechanics, PIV, Cylindrical Lens, High Power LED Copyright © 2019, Zongze Li ACKNOWLEDGMENTS First, I should sincerely thank to my professor, Dr. David Murphy, who gave me the chance to do this thesis and provided support, ideas and knowledge throughout the whole process. Without him, I might be still a layman of research. Just like Dr. Guldiken says: choosing a thesis will be much harder than taking 3 other courses. Sure it is, but I enjoyed it the whole time, which made me grow up in many areas. I should also give my genuine thanks to Dr. Carlowen Smith, Dr. Michael Celestin and Kerry Battles. Carlowen worked closely with me, let me know how to deal with a hard thing step by step, how things work in a researching process and how to find potential problem in a design. Dr. Celestin and Kerry helped me make my design come true, gave me a lot of great improvements on the design and generously taught me knowledge in electronic engineering. Finally, thanks again for all the people who helped me, without you, I could not have finished this paper so comprehensively. TABLE OF CONTENTS LIST OF TABLES ......................................................................................................................... iii LIST OF FIGURES ........................................................................................................................ v ABSTRACT ................................................................................................................................... ix CHAPTER 1: INTRODUCTION ................................................................................................... 1 CHAPTER 2: TANK SIMULATION ............................................................................................. 4 2.1 Introduction ................................................................................................................... 4 2.2 Model Geometry ........................................................................................................... 5 2.3 Boundary Conditions .................................................................................................... 8 2.3.1 Original Tank Boundary Conditions .............................................................. 9 2.3.2 Boundary Conditions for the Improved Tank .............................................. 10 2.4 Mathematic Methods .................................................................................................. 12 2.5 Simulation Results ...................................................................................................... 13 2.5.1 Original Tank Results ................................................................................... 13 2.5.2 Improved Tank Results ................................................................................ 16 2.6 Comparison of Distortions between Original and Improved Tanks ........................... 19 2.7 Conclusion .................................................................................................................. 20 CHAPTER 3: ILLUMINATION (GREEN LANTERN 2.0) FOR EXPERIMENT..................... 21 3.1 Motivation ................................................................................................................... 21 3.2 Principle ...................................................................................................................... 23 3.3 Experiment of LED Box for Green Lantern 2.0 ......................................................... 26 3.3.1 LED Selection .............................................................................................. 26 3.3.2 Using Different Cylindrical Lenses ............................................................. 29 3.3.3 Using Different Sizes of Fresnel Lenses ...................................................... 30 3.4 Green Lantern 2.0 Design ........................................................................................... 32 3.4.1 Heat Sink Assembly ..................................................................................... 33 3.4.2 LED Box Assembly ..................................................................................... 34 3.4.3 Plastic Sheet Assembly ................................................................................ 35 3.4.4 Electronics Assembly ................................................................................... 36 3.5 Comparison of New and Old Green Lanterns............................................................. 37 3.5.1 Thickness of the Light Sheet ........................................................................ 37 3.5.2 Brightness of the Light Sheet ....................................................................... 40 3.6 Thermal Performance of Both Green Lanterns ........................................................... 45 3.7 Discussion ................................................................................................................... 46 CHAPTER 4: EXPERMENT USING PIV ................................................................................... 48 i 4.1 Introduction ................................................................................................................. 48 4.2 Experiment Setup ........................................................................................................ 49 4.3 Results and Conclusion ............................................................................................... 50 CHAPTER 5: CONCLUSION AND FUTURE WORK .............................................................. 57 REFERENCES ............................................................................................................................. 59 APPENDIX A: TANK SIMULATION RESULTS ....................................................................... 61 APPENDIX B: EXPERIMENT DATA OF NEW & OLD GREEN LANTERNS ....................... 66 APPENDIX C: GREEN LANTERN 2.0 MANUAL ................................................................... 71 C.1 Material Used for Green Lantern 2.0 ......................................................................... 71 C.2 Electronic Box Area Specification ............................................................................. 74 ii LIST OF TABLES Table 2.1 Parameters of Original Tank ........................................................................................ 6 Table 2.2 Distance between Two Short Beams ............................................................................ 8 Table 2.3 Aluminum Physical Properties .................................................................................... 8 Table 2.4 Acrylic Sheet Physical Properties ................................................................................ 9 Table 2.5 Results of Tank Simulation ........................................................................................ 15 Table 2.6 Results of Improved Tank Simulation ....................................................................... 18 Table 3.1 Focal Length of Fresnel Lens Vs Width of Image ..................................................... 32 Table 3.2 Divergence Angle for Both Green Lanterns .............................................................. 40 Table 3.3 Efficiency of Green Lantern 2.0 ................................................................................ 42 Table B.1 Brightness at Opening of Green Lantern 2.0 (Unit: lux) ........................................... 66 Table B.2 Brightness at Opening of Green Lantern (Unit: lux) ................................................. 66 Table B.3 Brightness 50cm away above Opening of Green Lantern 2.0 (Unit: lux) ................. 67 Table B.4 Brightness 50cm away above Opening of Green Lantern (Unit: lux) ....................... 67 Table B.5 Light Sheet Thickness of Green Lantern at 50cm above Opening (Unit: cm) .......... 67 Table B.6 Light Sheet Thickness of Green Lantern 2.0 at 50cm above Opening (Unit: cm) .... 68 Table B.7 Light Sheet Thickness of Green Lantern at Opening (Unit: mm) ............................. 68 Table B.8 Light Sheet Thickness of Green Lantern 2.0 at Opening (Unit: mm) ....................... 68 Table B.9 Temperature Vs Time for Heat Sink of Green Lantern 2.0 .......................................
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