vii TABLE OF CONTENTS CHAPTER 1 2 TITLE PAGE DECLARATION ii DEDICATION iii ACKNOWLEDEMENT iv ABSTRACT v ABSTRAK vi TABLE OF CONTENTS vii LIST OF TABLES x LIST OF FIGURES xii LIST OF SYMBOLS xx LIST OF APPENDICES xxv INTRODUCTION 1 1.1 Research Background 1 1.2 Problem Statements 5 1.3 Objectives and Scope 6 1.4 Significance of Study 7 1.5 Thesis Outline 8 LITERATURE REVIEW 10 2.1 Introduction 10 2.2 Flow over a Stretching Sheet in a Micropolar Fluid 10 2.3 Flow over a Shrinking Sheet in a Micropolar Fluid 15 2.4 Micropolar Fluid in a Porous Medium 20 viii 3 4 MATHEMATICAL FORMULATION 23 3.1 Introduction 23 3.2 Governing Equations 23 3.3 Boussinesq Approximation 29 3.4 Non-dimensional Equations 31 3.5 Boundary Layer Approximation 34 3.6 Non-similar Transformation 36 3.7 Physical Quantities 38 THERMOPHORESIS AND SUCTION OR INJECTION 40 EFFECTS ON THE STAGNATION POINT FLOW TOWARDS A HORIZONTAL SHEET 5 4.1 Introduction 40 4.2 Governing Equations 41 4.3 Non-dimensional Equations 43 4.4 Non-similar Transformation 43 4.5 Solution Procedure 45 4.6 Results and Discussions 46 THERMOPHORESIS AND SLIP EFFECTS ON THE 64 STAGNATION POINT FLOW TOWARDS A SHRINKING SHEET 6 5.1 Introduction 64 5.2 Governing Equations 65 5.3 Non-similar Transformation 66 5.4 Results and Discussions 67 MIXED CONVECTION STAGNATION POINT FLOW 85 TOWARDS A PERMEABLE SHRINKING SHEET WITH SLIP EFFECT 6.1 Introduction 85 6.2 Governing Equations 86 6.3 Non-dimensional Equations and Boundary Layer Approximation 87 ix 7 6.4 Non-similar Transformation 88 6.5 Results and Discussions 90 MIXED CONVECTION STAGNATION POINT FLOW 107 TOWARDS A STRETCHING SHEET IN A POROUS MEDIUM WITH SORET AND DUFOUR EFFECTS 8 7.1 Introduction 107 7.2 Governing Equations 108 7.3 Non-dimensional Equations and Boundary Layer Approximation 109 7.4 Non-similar Transformation 111 7.5 Results and Discussions 113 CONCLUSION 132 8.1 Summary of Research 132 8.2 Suggestion for Future Research 136 REFERENCES 138 Appendices A-C 150-182 x LIST OF TABLES TABLE NO. 4.1 4.2 TITLE PAGE Comparison of values of the skin friction of final steady-state flow ( 1) for various values of f 0 when K M n 0 48 Results of the skin friction for various values of K 1, M 1, f0 1, n 0.5, 0.6 with different step sizes. 49 4.3 The skin friction, the Nusselt number and the Sherwood number for various values of f 0 and when K 1, M 1, Pr 0.71, 49 Sc 0.94, 0.2, n 0.5 5.1 Comparison of the values of f ''(0) for stretching sheet in the absence of concentration , thermophoresis and slip parameter 70 Comparison of the values of f ''(0) for shrinking sheet when K 0 in the absence of concentration , thermophoresis and slip parameter . 71 The reduced skin friction, the reduced Nusselt number and the reduced Sherwood number for various values of and when K 1, M 1,Pr 0.71, Sc 0.94, 0.2, n 0, 0.2 71 The reduced skin friction, the reduced Nusselt number and the reduced Sherwood number for various values of and when K 1, M 1,Pr 0.71, Sc 0.94, 0.2, n 0, 0.75 72 Comparison of the values of f ''(0) for stretching sheet in the absence of concentration , magnetic parameter M and slip parameter 93 5.2 5.3 5.4 6.1 6.2 Comparison of the values of f ''(0) for shrinking sheet when K 0 in the absence of concentration , magnetic parameter xi 6.3 6.4 7.1 7.2 7.3 M and slip parameter . 94 The reduced skin friction, the reduced Nusselt number and the reduced Sherwood number for various values of f 0 , and when K 1, M 1,Pr 0.71, Sc 0.94, n 0, 0.2, 1, 0.6 94 The reduced skin friction, the reduced Nusselt number and the the reduced Sherwood number for various values of f 0 , and when K 1, M 1,Pr 0.71, Sc 0.94, n 0, 0.75, 1, 0.6 95 Comparison of the values of C fx Re1/x 2 and Nux / Re1/x 2 for different values of Pr in absence of concentration , Soret S r and Dufour D f effects when 1 and 1 117 Comparison of the values of C fx Re1/x 2 and Nux / Re1/x 2 for different values of Pr in absence of concentration , Soret S r and Dufour effects D f when 1 and 1 117 Values of C fx Re1/x 2 , Nux / Re1/x 2 and Shx / Re1/x 2 for different values of and MD when K 1, Pr 0.71, Sc 0.94, n 0, 1, Sr 0.2, D f 0.2, 1, 0.6 for assisting 0 and opposing 0 flow 7.4 118 Values of C fx Re1/x 2 , Nux / Re1/x 2 and Shx / Re1/x 2 for different values of and S r when K 1, MD 1.5, Pr 0.71, Sc 0.94, n 0.5, 1, D f 0.2, 1, 0.6 for assisting 0 and opposing 0 flow 7.5 119 Values of C fx Re1/x 2 , Nux / Re1/x 2 and Shx / Re1/x 2 for different values of and D f when K 1, MD 1.5, Pr 0.71, Sc 0.94, n 0.5, 1, Sr 0.2, 1, 0.6 for assisting 0 and opposing 0 flow 120 xii LIST OF FIGURES FIGURE NO. TITLE PAGE 4.1 Physical model and coordinate system 4.2 The velocity profiles for various values of when K 1, M 1, n 0.5 (a) suction f 0 1 and (b) injection f 0 1 4.3 41 50 The microrotation profiles for various values of when K 1, M 1 , n 0.5 (a) suction f 0 1 and (b) injection f 4.4 0 1 51 The temperature profiles for various values of when K 1, M 1, Pr 0.71, Sc 0.94, n 0.5 (a) suction f 0 1 and (b) injection f 0 1 4.5 The concentration profiles for various values of when K 1, M 1, Pr 0.71, Sc 0.94, 0.2, n 0.5 (a) suction f 4.6 0 1 and (b) injection f 0 1 53 The velocity profiles for various values of when K 1, M 1, n 0 (a) suction f 0 1 and (b) injection f 0 1 4.7 52 54 The microrotation profiles for various values of when K 1, M 1, n 0 (a) suction f 0 1 and (b) injection f 4.8 0 1 55 The temperature profiles for various values of when K 1, M 1, Pr 0.71, Sc 0.94, n 0 (a) suction f 0 1 and (b) injection f 0 1 56 xiii 4.9 The concentration profiles for various values of when K 1, M 1, Pr 0.71, Sc 0.94, 0.2, n 0 (a) suction f 4.10 4.11 4.12 4.13 4.14 4.15 4.16 4.17 4.18 4.19 4.20 4.21 5.1 0 1 and (b) injection f 0 1 57 The velocity profiles for various values of f 0 when K 1, M 1, n 0, 0.4 58 The microrotation profiles for various values of f 0 when K 1, M 1, n 0, 0.4 58 The temperature profiles for various values of f 0 when K 1, M 1, Pr 0.71, Sc 0.94, n 0, 0.4 59 The concentration profiles for various values of f 0 when K 1, M 1, Pr 0.71, Sc 0.94, 0.2, n 0, 0.4 59 The velocity profiles for various values of K for suction or injection when M 1, n 0, 0.6 60 The microrotation profiles for various values of K for suction or injection when M 1, n 0, 0.6 60 The concentration profiles for various values of for suction or injection when K 1, M 1, Pr 0.71, Sc 0.94, n 0, 0.6 61 The velocity profiles for various values of M for suction or injection when K 1, n 0, 0.6 61 The microrotation profiles for various values of M for suction suction or injection when K 1, n 0, 0.6 62 Variation of the skin friction with for different values of suction or injection when K 1, M 1, n 0.5 62 Variation of the Nusselt number with for different values of suction or injection when K 1, M 1, Pr 0.71, Sc 0.94, n 0.5 63 Variation of the Sherwood number with for different values of suction or injection when K 1, M 1, Pr 0.71, Sc 0.94, 0.2, n 0.5 63 Physical model and coordinate system 65 xiv 5.2 The velocity profiles for various values of when K 1, M 1, 73 n 0, 0.2, 0.8 5.3 The microrotation profiles for various values of when K 1, M 1, n 0, 0.2, 0.8 73 The temperature profiles for various values of when K 1, M 1, Pr 0.71, Sc 0.94, n 0, 0.2 0.8 74 The concentration profiles for various values of when K 1, M 1, Pr 0.71, Sc 0.94, 0.2, n 0, 0.2 , 0.8 74 The velocity profiles for various values of when K 1, M 1, n 0, 0.75, 0.8 75 The microrotation profiles for various values of when K 1, M 1, n 0, 0.75, 0.8 75 The temperature profiles for various values of when K 1, M 1, Pr 0.71, Sc 0.94, n 0, 0.75, 0.8 76 The concentration profiles for various values of when K 1, M 1, Pr 0.71, Sc 0.94, 0.2, n 0, 0.75, 0.8 76 5.4 5.5 5.6 5.7 5.8 5.9 5.10 The velocity profiles for various values of when K 1, M 1, 77 0.75, 0.2 for (a) n 0.5 and (b) n 0 5.11 The microrotation profiles for various values of when K 1, M 1, 0.75, 0.2 for (a) n 0.5 and (b) n 0 78 The temperature profiles for various values of when K 1, M 1, Pr 0.71, Sc 0.94, 0.75, 0.2 for (a) n 0.5 and (b) n 0 79 The concentration profiles for various values of when K 1, M 1, Pr 0.71, Sc 0.94, 0.2, 0.75, 0.2 for (a) n 0.5 and (b) n 0 80 The concentration profiles for various values of when K 1, M 1, Pr 0.71, Sc 0.94, n 0, 0.75, 0.2, 0.8 81 5.12 5.13 5.14 5.15 Variation of the reduced Sherwood number with for different values of when K 1, M 1, Pr 0.71, Sc 0.94, n 0, 0.75, 0.2 81 xv 5.16 Variation of the reduced skin friction with for different values of when K 1, M 1, n 0, 0.2 82 5.17 Variation of the reduced Nusselt number with for different values of when K 1, M 1, Pr 0.71, Sc 0.94, 0.2, n 0, 0.2 82 Variation of the reduced Sherwood number with for different values of when K 1, M 1, Pr 0.71, Sc 0.94, n 0, 0.2 83 Variation of the reduced skin friction with for different values of when K 1, M 1, n 0, 0.75 83 Variation of the reduced Nusselt number with for different values of when K 1, M 1, Pr 0.71, Sc 0.94, n 0, 0.75 84 5.18 5.19 5.20 5.21 Variation of the reduced Sherwood number with for different values of when K 1, M 1, Pr 0.71, Sc 0.94, 0.2, n 0, 0.75 84 6.1 Physical model and coordinate system 87 6.2 The velocity profiles for various values of when K 1, M 1, Pr 0.71, Sc 0.94, n 0, f0 1, 0.75, 0.2, 1, 96 0.8 6.3 The microrotation profiles for various values of when K 1, M 1, Pr 0.71, Sc 0.94, n 0, f0 1, 0.75, 0.2, 1, 0.8 96 6.4 The temperature profiles for various values of when K 1, M 1, Pr 0.71, Sc 0.94, n 0, f0 1, 0.75, 0.2, 1, 97 0.8 6.5 The concentration profiles for various values of when K 1, M 1, Pr 0.71, Sc 0.94, n 0, f0 1, 0.75, 0.2, 1, 0.8 97 6.6 The velocity profiles for various values of when K 1, M 1, 98 Pr 0.71, Sc 0.94, n 0, f0 1, 0.2, 1, 0.8 6.7 The microrotation profiles for various values of when K 1, xvi 6.8 6.9 6.10 M 1, Pr 0.71, Sc 0.94, n 0, f0 1, 0.2, 1, 0.8 98 The temperature profiles for various values of when K 1, M 1, Pr 0.71, Sc 0.94, n 0, f0 1, 0.2, 1, 0.8 99 The concentration profiles for various values of when K 1, M 1, Pr 0.71, Sc 0.94, n 0, f0 1, 0.2, 1, 0.8 99 The velocity profiles for various values of M when K 1, Pr 0.71, Sc 0.94, n 0, f0 1, 0.75, 0.2, 1, 0.8 100 6.11 The microrotation profiles for various values of M when K 1, Pr 0.71, Sc 0.94, n 0, f0 1, 0.75, 0.2, 1, 100 0.8 6.12 The temperature profiles for various values of M when K 1, Pr 0.71, Sc 0.94, n 0, f0 1, 0.75, 0.2, 1, 0.8 101 6.13 The concentration profiles for various values of M when K 1, Pr 0.71, Sc 0.94, n 0, f0 1, 0.75, 0.2, 1, 101 0.8 6.14 The velocity profiles for various values of K when M 1, Pr 0.71, Sc 0.94, n 0, f0 1, 0.75, 0.2, 1, 0.8 102 6.15 The microrotation profiles for various values of K when M 1, Pr 0.71, Sc 0.94, n 0, f0 1, 0.75, 0.2, 1, 102 0.8 6.16 The temperature profiles for various values of K when M 1, Pr 0.71, Sc 0.94, n 0, f0 1, 0.75, 0.2, 1, 0.8 103 6.17 The concentration profiles for various values of K when M 1, Pr 0.71, Sc 0.94, n 0, f0 1, 0.75, 0.2, 1, 103 0.8 6.18 Variation of the reduced skin friction with for different values of and f 0 when K 1, M 1,Pr 0.71, Sc 0.94, n 0, 0.2, 104 1, 0.6 xvii 6.19 Variation of the reduced Nusselt number with for different values of and f 0 when K 1, M 1, Pr 0.71, Sc 0.94, n 0, 104 0.2, 1, 0.6 6.20 Variation of the reduced Sherwood number with for different values of and f 0 when K 1, M 1,Pr 0.71, Sc 0.94, n 0, 105 0.2, 1, 0.6 6.21 Variation of the reduced skin friction with for different values of and f 0 when K 1, M 1, Pr 0.71, Sc 0.94, n 0, 105 0.75, 1, 0.6 6.22 Variation of the reduced Nusselt number with for different values of and f 0 when K 1, M 1, Pr 0.71, Sc 0.94, n 0, 0.75, 1, 0.6 106 6.23 Variation of the reduced Sherwood number with for different values of and f 0 when K 1, M 1,Pr 0.71, Sc 0.94, n 0, 106 0.75, 1, 0.6 7.1 Physical model and coordinate system 7.2 The velocity profiles for various values of when K 1, MD 1.5, Pr 0.71, Sc 0.94, n 0.5, 1, Sr 0.2, Df 0.2, 1, 0.2 7.3 122 The velocity profiles for various values of S r when K 1, MD 1.5, Pr 0.71, Sc 0.94, n 0.5, 1, Df 0.2, 1, 0.8 7.7 122 The concentration profiles for various values of when K 1, MD 1.5, Pr 0.71, Sc 0.94, n 0.5, 1, Sr 0.2, Df 0.2, 1, 0.2 7.6 121 The temperature profiles for various values of when K 1, MD 1.5, Pr 0.71, Sc 0.94, n 0.5, 1, Sr 0.2, Df 0.2, 1, 0.2 7.5 121 The microrotation profiles for various values of when K 1, MD 1.5, Pr 0.71, Sc 0.94, n 0.5, 1, Sr 0.2, Df 0.2, 1, 0.2 7.4 108 The microrotation profiles for various values of S r when K 1, 123 xviii MD 1.5, Pr 0.71, Sc 0.94, n 0.5, 1, Df 0.2, 1, 7.8 7.9 7.10 0.8 123 The temperature profiles for various values of S r when K 1, MD 1.5, Pr 0.71, Sc 0.94, n 0.5, 1, Df 0.2, 1, 0.8 124 The concentration profiles for various values of S r when K 1, MD 1.5, Pr 0.71, Sc 0.94, n 0.5, 1, Df 0.2, 1, 0.8 124 The velocity profiles for various values of D f when K 1, MD 1.5, Pr 0.71, Sc 0.94, n 0.5, 1, Sr 0.2, 1, 0.8 7.11 The microrotation profiles for various values of D f when K 1, MD 1.5, Pr 0.71, Sc 0.94, n 0.5, 1, Sr 0.2, 1, 0.8 7.12 7.15 126 The concentration profiles for various values of D f when K 1, MD 1.5, Pr 0.71, Sc 0.94, n 0.5, 1, Sr 0.2, 1, 0.8 7.14 125 The temperature profiles for various values of D f when K 1, MD 1.5, Pr 0.71, Sc 0.94, n 0.5, 1, Sr 0.2, 1, 0.8 7.13 125 126 Variation of the skin friction with for different values of MD when K 1, M 1, Pr 0.71, Sc 0.94, n 0.5, 1, Sr 0.2, Df 0.2, 1, 0.6 127 Variation of the Nusselt number with for different values of MD when K 1, M 1, Pr 0.71, Sc 0.94, n 0.5, 1, Sr 0.2, Df 0.2, 1, 0.6 127 7.16 Variation of the Sherwood number with for different values of MD when K 1, M 1, Pr 0.71, Sc 0.94, n 0.5, 1, Sr 0.2, Df 0.2, 1, 0.6 128 7.17 Variation of the skin friction with for different values of S r when K 1, MD 1.5, Pr 0.71, Sc 0.94, n 0.5, 1, Df 0.2, 1, 0.6 128 xix 7.18 Variation of the Nusselt number with for different values of S r when K 1, MD 1.5, Pr 0.71, Sc 0.94, n 0.5, 1, Df 0.2, 1, 0.6 7.19 7.20 7.21 Variation of the Sherwood number with for different values of S r when K 1, MD 1.5, Pr 0.71, Sc 0.94, n 0.5, 1, Df 0.2, 1, 0.6 129 Variation of the skin friction with for different values of D f when K 1, MD 1.5, Pr 0.71, Sc 0.94, n 0.5, 1, Sr 0.2, 1, 0.6 130 Variation of the Nusselt number with for different values of D f when K 1, MD 1.5, Pr 0.71, Sc 0.94, n 0.5, 1, Sr 0.2, 1, 0.6 7.22 129 130 Variation of the Sherwood number with for different values of D f when K 1, MD 1.5, Pr 0.71, Sc 0.94, n 0.5, 1, Sr 0.2, 1, 0.6 131 xx LIST OF SYMBOLS Roman Letters a, b - positive constants b* - induced magnetic field B - magnetic field vector B0 - externally imposed magnetic strength in the y direction cs - concentration susceptibility C - fluid concentration C - nondimensional fluid concentration C - external concentration Cw - surface concentration Cp - specific heat at constant pressure C fx - skin friction coefficient C - concentration difference Da 1 - inverse Darcy number Df - Dufour number Dm - mass diffusivity E - electric field vector f - non-dimensional velocity f0 - suction or injection parameter F - body force Fx - scalar force in x component g - magnitude of the acceleration due to gravity Gc - concentration Grashof number xxi Gr - thermal Grashof number h - non-dimensional microrotation j - microinertia density J - electric current density vector k - thermal conductivity k1 - permeability of porous medium k1* - vortex viscosity kT - thermal diffusion ratio K - micropolar material parameter L - characteristic length L1 - slip length mw - non-dimensional mass flux from the surface of the wall M - magnetic parameter MD - effective Darcy number n - ratio of the microrotation vector component to the fluid skin friction at the wall N - component of the microrotation vector normal to x y plane N - non-dimensional component of the microrotation vector normal to x y plane Nu x - Nusselt number O - order of magnitude p - pressure p - non-dimensional pressure pd - dynamic pressure ph - hydrostatic pressure Pr - Prandtl number qw - non-dimensional heat flux from the surface of the wall Re - Reynolds number Sc - Schmidt number Shx - Sherwood number xxii Sr - Soret number t - time t - non-dimensional time T - fluid temperature T - non-dimensional fluid temperature Tm - mean fluid temperature Tr - reference temperature Tw - surface temperature T - external temperature T - temperature difference ue ( x ) - dimensional external velocity ue ( x) - non-dimensional external velocity uw ( x ) - dimensional velocity along the sheet uw ( x ) - non-dimensional velocity along the sheet u,v - velocity components along x , y axes u, v - non-dimensional velocity components along x and y U - reference velocity V - dimensional velocity vector VT - dimensional thermophoretic velocity v0 - velocity suction or injection x, y - cartesian coordinates along the plate and normal to it, respectively x, y - non-dimensional cartesian coordinates along the wall and normal to it, respectively - gradient Greek Letters - thermal diffusivity - coefficient of thermal expansion xxiii * - coefficient of concentration expansion - partial derivative - spin gradient viscosity , , - transformed coordinate - slip parameter * - boundary layer thickness - non-dimensionl temperature - thermal conductivity * - thermophoretic coefficient - dynamic viscosity m - magnetic permeability - kinematic viscosity - density - fluid density in the ambient medium - shrinking parameter * - convergence tolerance - non-dimensionl concentration - stream function - thermophoretic parameter w - non-dimensional wall shear stress or skin friction * - concentration buoyancy parameter - mixed convection parameter - electrical conductivity - velocity ratio parameter - buoyancy ratio Subscripts ,e - far field or free stream condition w - wall condition d - dynamic pressure xxiv p - constant pressure condition Superscripts k - number of iteration ' - differentiation with respect to xxv LIST OF APPENDICES APPENDIX TITLE A The Keller-Box Method B FORTRAN Program for the Problem of the PAGE 150 Thermophoresis and Suction or Injection Effects on the Stagnation Point Flow towards a C Horizontal Sheet 164 Status of Publications 180