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Suspended Sediment Concentration Profiles in the Bottom Boundary Layer W&M ScholarWorks Dissertations, Theses, and Masters Projects Theses, Dissertations, & Master Projects 1993 Suspended sediment concentration profiles in the bottom boundary layer Jingping Xu College of William and Mary - Virginia Institute of Marine Science Follow this and additional works at: https://scholarworks.wm.edu/etd Part of the Geology Commons, and the Oceanography Commons Recommended Citation Xu, Jingping, "Suspended sediment concentration profiles in the bottom boundary layer" (1993). Dissertations, Theses, and Masters Projects. Paper 1539616914. https://dx.doi.org/doi:10.25773/v5-55tq-zj21 This Dissertation is brought to you for free and open access by the Theses, Dissertations, & Master Projects at W&M ScholarWorks. It has been accepted for inclusion in Dissertations, Theses, and Masters Projects by an authorized administrator of W&M ScholarWorks. For more information, please contact [email protected]. INFORMATION TO USERS This manuscript has been reproduced from the microfilm master. UMI films the text directly from the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter face, while others may be from any type of computer printer. The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleedthrough, substandard margins, and improper alignment can adversely afreet reproduction. In the unlikely event that the author did not send UMI a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. Oversize materials (e.g., maps, drawings, charts) are reproduced by sectioning the original, beginning at the upper left-hand corner and continuing from left to right in equal sections with small overlaps. Each original is also photographed in one exposure and is included in reduced form at the back of the book. Photographs included in the original manuscript have been reproduced xerographically in this copy. Higher quality 6" x 9" black and white photographic prints are available for any photographs or illustrations appearing in this copy for an additional charge. Contact UMI directly to order. University Microfilms International A Bell & Howell Information Company 3 0 0 North Z eeb Road. Ann Arbor. M! 48106-1346 USA 313/761-4700 800/521-0600 Order Number 9326237 Suspended sediment concentration profiles in the bottom boundary layer Xu, Jingping, Ph.D. The College of William and Mary, 1993 UMI 300 N. Zeeb Rd. Ann Aibor, MI 48106 SUSPENDED SEDIMENT CONCENTRATION PROFILES IN THE BOTTOM BOUNDARY LAYER A Dissertation Presented to The Faculty of the School of Marine Science The College of William and Mary in Virginia In Partial Fulfillment Of the Requirements for the Degree of Doctor of Philosophy by Jingping Xu 1993 APPROVAL SHEET This dissertation is submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy Jingping Xu Approved, March 1993 L. Donelson Wright, Ph.D. Committee Chairman/Advisor John D. Boon, III, Ph.D. :"t> m Jr ?{' Albert Y. Kuo, Ph.D. ;obert J. D| Ole S. Madsen, Sc.D, Massachusetts Institute of Technology Cambridge, Massachusetts This thesis is dedicated with love to Jane and Lucy TABLE OF CONTENTS ACKNOWLEDGMENTS ......................................................................................................... vi LIST OF TABLES ...................................................................................................................... vii LIST OF FIGURES........................................................................................................................... viii LIST OF SYMBOLS ......................................................................................................................... x ABSTRACT........................................................................................................................................ xv 1. INTRODUCTION ........................................................................................................................ 2 2. METHODOLOGY AND DATA ANALYSIS ......................................................................... 6 2.1 Introduction .................................................................................................................... 6 2.2 Description of the research site ................................................................................... 7 2.3 Instrument settings ........................................................................................................ 11 2.4 Analysis of Hydrodynamics data ................................................................................ 13 2.4.1 Derivation of u0 ............................................................................................. 13 2.4.2 Derivation of 6 ............................................................................................. 14 2.4.3 Derivation of a,,, ub and T .......................................................................... 17 2.5 Preliminary analysis of the OBS data ......................................................................... 17 3. A WAVE-CURRENT-SEDIMENT INTERACTION BOUNDARY LAYER MODEL........................................................................................ 24 3.1 Introduction .................................................................................................................... 24 3.2 Governing equations ................................................... 29 3.3 Eddy viscosity model ..................................... 31 3.4Solutions ........................................................................................................................ 36 3.4.1 About the continuity of the stability parameter ..................................... 39 - iv - 3.4.2 Solutions of current and mean concentration .......................................... 40 3.5 The reference concentration model ........................................................................... 47 4. BOTTOM ROUGHNESS UNDER WAVE-CURRENT-SEDIMENT INTERACTION ... 49 4.1 Introduction .................................................................................................................... 49 4.2 Existing roughness models ................................................................. 50 4.3 Test of roughness models using field data ................................................................. 56 4.4 A new roughness m o d el ............................................................................................... 63 5. EFFECTS OF STRATIFICATION AND SEDIMENT COMPOSITION ON SUSPENDED SEDIMENT CONCENTRATION PROFILES ............................ 73 5.1 Introduction ........................... 73 5.2 Effect of stratification ................................................. 74 5.3 Effect of sediment composition .................................................................... 76 5.4 Summary and discussions ............................................................................................ 92 6. REFERENCE CONCENTRATION AND SUSPENSION COEFFICIENT ........................ 105 6.1 Introduction ........ 105 6.2 Computation of suspension coefficient .......................................................... 106 6.3 Results and discussions ................................................................................................ 107 6.4 Computation of y 0 using the concentration of silt and clay ...................................... 112 6.5Summary ........................................................................................................................ 116 7. CONCLUSION ............................................................................................................................ 117 LITERATURE CITED...................................................................................................................... 124 VITAE................................................................................................................................................ 131 - v - ACKNOWLEDGEMENTS I would like to thank my parents for making everything possible from the very beginning. I am grateful to Don Wright for his support, enthusiasm, and contribution to my scientific, as well as personal growth. It is hard to conceive of a better mentor and friend. Thanks go to each of my committee member for their time and efforts for the review of this thesis. I would like to thank Ole Madsen for providing inspirations, scientific guidance and pleasant humors. I would also like to thank John Boon, A1 Kuo and Bob Diaz for their contributions to my education through their courses and many insightful conversations. Thanks also go to Jerome Maa for introducing me to numerical approaches and data acquisition instruments. I would like to acknowledge the help of Linda Schaffner, Suzette Kimball, Dan Hepworth and Woody Hobbs for their assistance. Special thanks go to Bob Gammisch and Frank Farmer, who made the field work successful by designing, building and maintaining the equipments. Finally, I would like to thank my wife, Jane, for her support and encouragement. This research was supported by Virginia Institute of Marine Science and the National Science Foundation, Marine Geology and Geophysics Grant OCE-9017828. LIST OF TABLES 2.1 Input parameters used in the boundary layer model ................................................
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