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Information to Users 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 affect 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 C om pany 300 North Z eeb Road. Ann Arbor. Ml 48106-1346 USA 313/761-4700 800/521-0600 Order Number 9325512 Investigation and modeling of complex interfacial effects for porous/non-porous configurations Huang, Po-Chuan, Ph.D. The Ohio State University, 1993 UMI 300 N. Zeeb Rd. Ann Arbor, MI 48106 INVESTIGATION AND MODELING OF COMPLEX INTERFACIAL EFFECTS FOR POROUS/NON-POROUS CONFIGURATIONS DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of the Ohio State University By Po-Chuan Huang, B.S., M.S. The Ohio State University 1993 Dissertation Committee: Approved by Prof. K. Vafai Prof. T. E. Blue Adv Prof. Robert H. Essenhigh Department of Mechanibal E eenng To My Parents, Wife and My Beloved Daughter ACKNOWLEDGMENTS I would like to express my deepest appreciation to Prof. K. Vafai for his guidance and insight throughout the research and for his infinite patience. I also thank my committee members, Prof. T. E. Blue, Robert H. Essenhigh and S. Roklin for the time they took to make critical comments. I am grateful to Ohio Supercomputer Center for providing me with the computer time for the numerical computation. In addition, I am grateful for many helpful discussions related to this study from James Wang, Hsing-Sen Hsiao, Wen-Tong Wang and my colleagues. Finally, I want to express my indebtedness to my wife, Meir-Chyun Tzou for her understanding and everlasting support, and my daughter Rouh-Yau Huang since I was frequently not available at home while they really needed me. Finally, I would like to dedicate this dissertation to my parents, brothers, and sisters for their love and support during the course of study. VITA January 20, 1955 ..................................................... Born-Tainan, Taiwan, R. O. C. 1978 ........................................................................... B.S., National Chiao Tung University, Hsichu, Taiwan, R. O. C. 1983 ........................................................................... M.S., Tatung Institute of Technology, Taipei, Taiwan R. O. C. 1984-1989 ................................................................. Instructor, Tung-Nan College and China Maritime College, Taipei, Taiwan 1990-1993 ................................................................. Graduate Student The Ohio State University Columbus, Ohio FIELD OF STUDY Major Field: Mechanical Engineering Studied in Heat transfer and Fluid Mechanics Prof. K. Vafai TABLE OF CONTENTS ACKNOWLEDGEMENTS..............................................................................................iii VITA ....................................................................................................................................... iv LIST OF TABLES.................................................................................................................vii LIST OF FIGURES.............................................................................................................viii NOMENCLATURE...........................................................................................................xviii CHAPTER PAGE I . GENERAL INTRODUCTION........................................................................1 II. ANALYSIS OF FLOW AND HEAT TRANSFER OVER AN EXTERNAL BOUNDARY COVERED WITH A POROUS SUBSTRATE 2.1 Statement of the problem ...........................................................7 2.2 Theory of the problem .......................................................................10 2.3 Analysis and solution ........................................................................ 14 2.4 Results and discussion .....................................................................20 III. FORCED CONVECTION OVER INTERMITTENTLY EMPLACED POROUS CAVITIES 3.1 Statement of the problem ................................................................. 24 3.2 Analysis and formulation ................................................................. 27 3.3 Numerical scheme ............................................................................. 34 3.4 Results and discussion .............................................................38 IV. FORCED CONVECTION OVER POROUS BLOCK ARRAY 4.1 Statement of the problem ................................................................. 56 4.2 Theory .................................................................................................60 4.3 Numerical method and procedure ....................................................66 4.4 Results and discussion .................................................. 71 V. AN INVESTIGATION OF FORCED CONVECTION THROUGH ALTERNATE POROUS CAVITY-BLOCK OBSTACLES 5.1 Statement of the problem ....................................................................97 5.2 Analysis ............................................................................................ 101 5.3 Numerical scheme .............................................................................108 5.4 Results and discussion ..................................................................... 115 VI. ANALYSIS OF FORCED CONVECTION ENHANCEMENT IN A CHANNEL USING POROUS BLOCKS 6.1 Statement of the problem ....................................................... 134 6.2 Mathematical formulation .................................................................138 6.3 Computational details .............................................................. 144 6.4 Results and discussion ..................................................................... 150 VII. INTERNAL HEAT TRANSFER AUGMENTATION IN A PARALLEL PLATE CHANNEL USING AN ALTERNATE SET OF POROUS CAVITY-BLOCK OBSTACLES 7.1 Statement of the problem ........................................................174 7.2 Theory ...........................................................................................178 7.3 Boundary conditions ........................................................................ 181 7.4 Numerical solution method ..............................................................187 7.5 Results and discussion .....................................................................194 VIII. CONCLUSIONS AND RECOMMENDATIONS 8.1 Conclusions .......................................................................................216 8.2 Recommendations for further research ........................................220 LIST OF REFERENCES..................................................................................................221 LIST OF TABLES TABLES PAGE 3.1 Input data of governing parameters for intermittently emplaced c a v itie s ...........................................................................................................39 5.1 Coefficients of equation (5.24) ................................................................. 110 LIST OF FIGURES FIGURES PAGE 2.1 Schematic diagram of the flow over an external boundary with anattached porous substrate ........................................................................... 11 2.2 Control volume for integral momentum analysis of 1) porous boundary layer, 2) interfacial region between the porous and fluid layers and 3) and the fluid boundary layer ..................................................15 2.3 (a) Velocity and (b) temperature distribution along the flat plate at three different locations, *=0.2, 0.5 and 0.8, for Re^ = 3 x105> Al =0.35, DaL = 8xl0"\ Pr=0.7, kf/r/ k f = 1 .0 ,H/L=0.02............21 2.4 Comparison of the integral solutions with numerical solutions for x-compoment interfacial velocity along the flat plate for AL = 0.35 , ReL = 3 x l 0 5, DaL = 8 x 10-6, / / /L=0.02 .............................................. 23 3.1 Schematic diagram of flow and heat transfer over intermittently emplaced porous cavities ............................................................................... 28 3.2 (a) The non-uniform grid system for the whole computational domain, (b) Local integration cell in the computational domain .............. 35 3.3 (a) Streamlines and (b) isotherms for flow over four obstructing porous cavities for
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