Heat transfer optimization of pulsating flow in corrugated channel Heat transfer optimization of pulsating flow in corrugated channel Heat transfer optimization of pulsating flow in corrugated channel luận văn tốt nghiệp,luận văn thạc sĩ, luận văn cao học, luận văn đại học, luận án tiến sĩ, đồ án tốt nghiệp luận văn tốt nghiệp,luận văn thạc sĩ, luận văn cao học, luận văn đại học, luận án tiến sĩ, đồ án tốt nghiệp
HANOI UNIVERSITY OF SCIENCE AND TECHNOLOGY MASTER THESIS Heat transfer optimization of pulsating flow in corrugated channel Hoang Van Quan hoangquan.b59@gmail.com School of Transportation Engineering Instructor: PhD Dinh Cong Truong Signature School: School of Transportation Engineering Ha Noi, 05/2020 SOCIALIST REPUBLIC OF VIETNAM Independence - Freedom - Happiness CERTIFICATION OF AMENDMENT OF MASTER'S THESIS Full name of author: Hoang Van Quan Subjet: Heat transfer optimization of pulsating flow in corrugated channel Major: Mechanical Engineering Student ID: CBC19003 The author, scientific instructor and dissertation Council confirm that the author has amended or supplemented the dissertation according to the date of the Council meeting date …… ………… with the following content: - Edit thesis according to the form - Specify the scope of the study - Detailed the thermal performance factor - Corrected the TPF term Hanoi 13th July, 2020 Instructor Author Dissertation Chair CONTENTS INTRODUCTION 1.1 Overview 1.2 Application NUMERICAL ANALYSIS 2.1 Simulation domain setup 2.2 Important parameters 2.3 Governing equations 2.4 Sub-grid scale model 11 2.5 CFD solver setup 11 Mesh generation 12 Boundary condition setup 13 RESULTS AND DISCUSSION 15 3.1 Grid dependency test and validation 15 3.2 Steady flow inside the corrugated channel 16 3.3 The effect of pulsating flow 20 3.4 The effect of amplitude of pulsating flow 28 3.5 The effect of frequency of pulsating flow 31 CONCLUSION 38 REFERENCES 39 APPENDIX 43 Abstract Pulsating flow has been widely studied for enhancement heat transfer Since there are plenty of applications, especially on the biological field Due to pulsating flow is a complex natural process, a number of parameters that effect on heat enhancement factors are unclear or lack of overall assess until recent years when the power of computer and advance CFD software is presented The OpenFOAM allows us to test and find the optimal parameters that most effect on heat enhancement The computational zone is the corrugated channel with the length of 300mm Using Large Eddy Simulation with the Wall-Adapting Local EddyViscosity sub-grid scale modal to solve the Navier-Stocks equations The mesh is refined at near the heated walls to make sure y+ at Reynolds number by 5371 is 0.1 The amplitude changes from to and the frequency change from to 25 Hz Reynolds numbers in the range of 2000 ≤ Re ≤ 6000 The heat enhancement factor, TPF is obtained as 1.76 which is the maximum value in the case of the corrugated channel for the Reynolds number of Re=2371 and the and the frequency f = 25 and amplitude A = 0.8 The 3D view of turbulence at different frequency and amplitude has been illustrated in detail Keywords: pulsating flow, heat transfer, thermal performance factor,, Nusselt number, OpenFOAM, friction factor LIST OF TABLES Table Effect of amplitude of pulsating flow 28 Table Effect of frequency of pulsating flow 31 LIST OF FIGURES Figure The distribution of investigated channels’ percentage Figure The distribution of investigated channels’ percentage Figure The heat exchanger used for aviation industry and different fin Figure Geometry parameter and computational domain Figure BlockMesh control parameter code 12 Figure Structure of the grid system 13 Figure Boundary condition setup files 13 Figure Grid-dependency test 15 Figure Validation of numerical results with experimental data 16 Figure 10 3D iso-surface of Q-criterion with regard to different Reynolds numbers 17 Figure 11 Instantaneous contour of spanwise temperature and vorticity of steady flow 18 Figure 12 Instantaneous contour of heat plate temperature of steady flow 19 Figure 13 Variation of Nusselt number with Reynolds number 21 Figure 14 Variation of fraction factor with Reynolds number 21 Figure 15 3D iso-surface of Q-criterion with different time state at Reynolds of 2371 22 Figure 16 Comparing instantaneous streamwise velocity for Reynolds of 2371 23 Figure 17 Comparing instantaneous streamwise vorticity for Reynolds of 2371 25 Figure 18 Comparing instantaneous streamwise temperature for Reynolds of 2371 26 Figure 19 3D comparing instantaneous streamwise vorticity for Reynolds of 2371 27 Figure 20 Effect of amplitude of pulsating flow at fixed Reynolds number of 2371 and frequency of 10Hz 29 Figure 27 Thermal performance factor for Re=2371 at constant frequency 10Hz 30 Figure 21 Effect of frequency of pulsating flow at fixed Reynolds number of 2371 and amplitude of 0.8 32 Figure 22 3D iso-surface of Q-criterion at amplitude = 0.8 and frequency = 25 for Reynolds of 2371 33 Figure 23 Instantaneous streamwise velocity for Reynolds of 2371 frequency 25 Hz, amplitude 0.8 34 Figure 24 Instantaneous streamwise vorticity for Reynolds of 2371 frequency 25 Hz, amplitude 0.8 34 Figure 25 Instantaneous streamwise temperature for Reynolds of 2371 frequency 25 Hz, amplitude 0.8 35 Figure 26 3D instantaneous temperature with different time state at Reynolds of 2371 frequency 25 Hz amplitude 36 Figure 28 Thermal performance factor for Re=2371 at constant amplitude A=0.8 37 Nomenclature 𝐴 𝐴𝑎𝑟𝑒𝑎 amplitude of the pulsating flow heated area (𝑚2 ) 𝐴𝑤 wavy wall amplitude (mm) 𝐶𝑝 specific heat (J/kg K) 𝐶𝑤 LES WALE constant 𝐷ℎ hydraulic diameter (= 4𝐻𝑊/(2(𝐻 + 𝑊 )) 𝐸 heat enhancement ratio 𝑓 friction factor 𝑓𝑝 frequency of the pulsating flow (Hz) ℎ heat transfer coefficient (W/m2 K) 𝐻 height of channel (m) 𝑘 thermal conductivity of the fluid (W/m K) 𝐿 wavy pitch (mm) 𝐿𝑡 distance from leading edge of corrugated plate (mm) 𝑁𝑢 time average of heated wall Nusselt number 𝑝 static pressure (Pa) 𝑞 heat flux (W/m2) 𝑅𝑒 Reynolds number 𝑇 temperature (K) 𝑇𝑃𝐹 thermal performance factor 𝑈0 inlet reference velocity (m/s) 𝑆𝑖𝑗 rate of strain tensor 𝑊 width of channel (mm) 𝑋 distance from leading edge of corrugated plate along corrugated surface (mm) 𝑦+ y in law-of-the-wall coordinate Greek symbols ∆ ∆x, ∆y, ∆z characteristic grid spacing grid spacing in x-, y-, z-directions ∆𝑝 pressure drop (Pa) 𝜃 wavy angle 𝜌 air density (kg/ m3) 𝜐 kinematic viscosity of the fluid (m2/s) 𝜐𝑡 eddy viscosity (m2/s) 𝜏𝑖𝑗 sub-grid scale stress tensor Abbreviations CFD Computational Fluid Dynamics ANNs Artificial Neural Networks LES Large Eddy Simulation WALE Wall-adapting Local Eddy-viscosity (WALE) model PISO Pressure-Implicit with Splitting of Operators Superscripts ̅ resolved grid scale (//y direction //(0.2 0.3 8) //(0.6 0.4 1) //(0.2 0.3 0.125) ) (//z direction (0.2 0.3 8) (0.6 0.4 1) (0.2 0.3 0.125) ) ) //tail block hex (88 96 97 89 90 98 99 91) ($gridx $gridy $gridz) simpleGrading ( (//x direction // (0.2 0.3 8) //(0.6 0.4 1) // (0.2 0.3 0.125) ) (//y direction //(0.2 0.3 8) //(0.6 0.4 1) //(0.2 0.3 0.125) ) (//z direction (0.2 0.3 8) (0.6 0.4 1) (0.2 0.3 0.125) ) ) hex (0 7) ($gridx $gridy $gridz) simpleGrading ( (//x direction // (0.2 0.3 8) //(0.6 0.4 1) // (0.2 0.3 0.125) ) (//y direction //(0.2 0.3 8) //(0.6 0.4 1) //(0.2 0.3 0.125) ) (//z direction (0.2 0.3 8) (0.6 0.4 1) (0.2 0.3 0.125) ) ) //(1 10 0.1) hex (1 10 11 6) ($gridx $gridy $gridz) simpleGrading ( (//x direction 46 // (0.2 0.3 8) //(0.6 0.4 1) // (0.2 0.3 0.125) ) (//y direction //(0.2 0.3 8) //(0.6 0.4 1) //(0.2 0.3 0.125) ) (//z direction (0.2 0.3 8) (0.6 0.4 1) (0.2 0.3 0.125) ) ) //(1 10 0.1) hex (8 12 13 10 14 15 11) ($gridx $gridy $gridz) simpleGrading ( (//x direction // (0.2 0.3 8) //(0.6 0.4 1) // (0.2 0.3 0.125) ) (//y direction //(0.2 0.3 8) //(0.6 0.4 1) //(0.2 0.3 0.125) ) (//z direction (0.2 0.3 8) (0.6 0.4 1) (0.2 0.3 0.125) ) ) //(1 10 0.1) hex (12 16 17 13 14 18 19 15) ($gridx $gridy $gridz) simpleGrading ( (//x direction // (0.2 0.3 8) //(0.6 0.4 1) // (0.2 0.3 0.125) ) (//y direction //(0.2 0.3 8) //(0.6 0.4 1) //(0.2 0.3 0.125) ) (//z direction (0.2 0.3 8) (0.6 0.4 1) (0.2 0.3 0.125) ) ) //(1 10 0.1) 47 hex (16 20 21 17 18 22 23 19) ($gridx $gridy $gridz) simpleGrading ( (//x direction // (0.2 0.3 8) //(0.6 0.4 1) // (0.2 0.3 0.125) ) (//y direction //(0.2 0.3 8) //(0.6 0.4 1) //(0.2 0.3 0.125) ) (//z direction (0.2 0.3 8) (0.6 0.4 1) (0.2 0.3 0.125) ) ) //(1 10 0.1) hex (20 24 25 21 22 26 27 23) ($gridx $gridy $gridz) simpleGrading ( (//x direction // (0.2 0.3 8) //(0.6 0.4 1) // (0.2 0.3 0.125) ) (//y direction //(0.2 0.3 8) //(0.6 0.4 1) //(0.2 0.3 0.125) ) (//z direction (0.2 0.3 8) (0.6 0.4 1) (0.2 0.3 0.125) ) ) //(1 10 0.1) hex (24 28 29 25 26 30 31 27) ($gridx $gridy $gridz) simpleGrading ( (//x direction // (0.2 0.3 8) //(0.6 0.4 1) // (0.2 0.3 0.125) ) (//y direction //(0.2 0.3 8) //(0.6 0.4 1) //(0.2 0.3 0.125) ) (//z direction (0.2 0.3 8) 48 (0.6 0.4 1) (0.2 0.3 0.125) ) ) //(1 10 0.1) hex (28 32 33 29 30 34 35 31) ($gridx $gridy $gridz) simpleGrading ( (//x direction // (0.2 0.3 8) //(0.6 0.4 1) // (0.2 0.3 0.125) ) (//y direction //(0.2 0.3 8) //(0.6 0.4 1) //(0.2 0.3 0.125) ) (//z direction (0.2 0.3 8) (0.6 0.4 1) (0.2 0.3 0.125) ) ) //(1 10 0.1) hex (32 36 37 33 34 38 39 35) ($gridx $gridy $gridz) simpleGrading ( (//x direction // (0.2 0.3 8) //(0.6 0.4 1) // (0.2 0.3 0.125) ) (//y direction //(0.2 0.3 8) //(0.6 0.4 1) //(0.2 0.3 0.125) ) (//z direction (0.2 0.3 8) (0.6 0.4 1) (0.2 0.3 0.125) ) ) //(1 10 0.1) hex (36 40 41 37 38 42 43 39) ($gridx $gridy $gridz) simpleGrading ( (//x direction // (0.2 0.3 8) //(0.6 0.4 1) // (0.2 0.3 0.125) ) (//y direction //(0.2 0.3 8) //(0.6 0.4 1) //(0.2 0.3 0.125) 49 ) (//z direction (0.2 0.3 8) (0.6 0.4 1) (0.2 0.3 0.125) ) ) //(1 10 0.1) hex (40 44 45 41 42 46 47 43) ($gridx $gridy $gridz) simpleGrading ( (//x direction // (0.2 0.3 8) //(0.6 0.4 1) // (0.2 0.3 0.125) ) (//y direction //(0.2 0.3 8) //(0.6 0.4 1) //(0.2 0.3 0.125) ) (//z direction (0.2 0.3 8) (0.6 0.4 1) (0.2 0.3 0.125) ) ) //(1 10 0.1) hex (44 48 49 45 46 50 51 47) ($gridx $gridy $gridz) simpleGrading ( (//x direction // (0.2 0.3 8) //(0.6 0.4 1) // (0.2 0.3 0.125) ) (//y direction //(0.2 0.3 8) //(0.6 0.4 1) //(0.2 0.3 0.125) ) (//z direction (0.2 0.3 8) (0.6 0.4 1) (0.2 0.3 0.125) ) ) //(1 10 0.1) hex (48 52 53 49 50 54 55 51) ($gridx $gridy $gridz) simpleGrading ( (//x direction // (0.2 0.3 8) //(0.6 0.4 1) // (0.2 0.3 0.125) ) (//y direction 50 //(0.2 0.3 8) //(0.6 0.4 1) //(0.2 0.3 0.125) ) (//z direction (0.2 0.3 8) (0.6 0.4 1) (0.2 0.3 0.125) ) ) //(1 10 0.1) hex (52 56 57 53 54 58 59 55) ($gridx $gridy $gridz) simpleGrading ( (//x direction // (0.2 0.3 8) //(0.6 0.4 1) // (0.2 0.3 0.125) ) (//y direction //(0.2 0.3 8) //(0.6 0.4 1) //(0.2 0.3 0.125) ) (//z direction (0.2 0.3 8) (0.6 0.4 1) (0.2 0.3 0.125) ) ) //(1 10 0.1) hex (56 60 61 57 58 62 63 59) ($gridx $gridy $gridz) simpleGrading ( (//x direction // (0.2 0.3 8) //(0.6 0.4 1) // (0.2 0.3 0.125) ) (//y direction //(0.2 0.3 8) //(0.6 0.4 1) //(0.2 0.3 0.125) ) (//z direction (0.2 0.3 8) (0.6 0.4 1) (0.2 0.3 0.125) ) ) //(1 10 0.1) hex (60 64 65 61 62 66 67 63) ($gridx $gridy $gridz) simpleGrading ( (//x direction // (0.2 0.3 8) //(0.6 0.4 1) 51 // (0.2 0.3 0.125) ) (//y direction //(0.2 0.3 8) //(0.6 0.4 1) //(0.2 0.3 0.125) ) (//z direction (0.2 0.3 8) (0.6 0.4 1) (0.2 0.3 0.125) ) ) //(1 10 0.1) hex (64 68 69 65 66 70 71 67) ($gridx $gridy $gridz) simpleGrading ( (//x direction // (0.2 0.3 8) //(0.6 0.4 1) // (0.2 0.3 0.125) ) (//y direction //(0.2 0.3 8) //(0.6 0.4 1) //(0.2 0.3 0.125) ) (//z direction (0.2 0.3 8) (0.6 0.4 1) (0.2 0.3 0.125) ) ) //(1 10 0.1) hex (68 72 73 69 70 74 75 71) ($gridx $gridy $gridz) simpleGrading ( (//x direction // (0.2 0.3 8) //(0.6 0.4 1) // (0.2 0.3 0.125) ) (//y direction //(0.2 0.3 8) //(0.6 0.4 1) //(0.2 0.3 0.125) ) (//z direction (0.2 0.3 8) (0.6 0.4 1) (0.2 0.3 0.125) ) ) //(1 10 0.1) hex (72 76 77 73 74 78 79 75) ($gridx $gridy $gridz) simpleGrading ( 52 (//x direction // (0.2 0.3 8) //(0.6 0.4 1) // (0.2 0.3 0.125) ) (//y direction //(0.2 0.3 8) //(0.6 0.4 1) //(0.2 0.3 0.125) ) (//z direction (0.2 0.3 8) (0.6 0.4 1) (0.2 0.3 0.125) ) ) //(1 10 0.1) hex (76 80 81 77 78 82 83 79) ($gridx $gridy $gridz) simpleGrading ( (//x direction // (0.2 0.3 8) //(0.6 0.4 1) // (0.2 0.3 0.125) ) (//y direction //(0.2 0.3 8) //(0.6 0.4 1) //(0.2 0.3 0.125) ) (//z direction (0.2 0.3 8) (0.6 0.4 1) (0.2 0.3 0.125) ) ) //(1 10 0.1) hex (80 84 85 81 82 86 87 83) ($gridx $gridy $gridz) simpleGrading ( (//x direction // (0.2 0.3 8) //(0.6 0.4 1) // (0.2 0.3 0.125) ) (//y direction //(0.2 0.3 8) //(0.6 0.4 1) //(0.2 0.3 0.125) ) (//z direction (0.2 0.3 8) (0.6 0.4 1) (0.2 0.3 0.125) 53 ) ) //(1 10 0.1) hex (84 88 89 85 86 90 91 87) ($gridx $gridy $gridz) simpleGrading ( (//x direction // (0.2 0.3 8) //(0.6 0.4 1) // (0.2 0.3 0.125) ) (//y direction //(0.2 0.3 8) //(0.6 0.4 1) //(0.2 0.3 0.125) ) (//z direction (0.2 0.3 8) (0.6 0.4 1) (0.2 0.3 0.125) ) ) //(1 10 0.1) ); edges ( ); boundary ( inlet { type patch; faces ( ( 92 93 95 94 ) ); } outlet { type patch; faces ( ( 96 97 99 98 ) ); } heatWall1 { type wall; faces ( (4567) ( 10 11 ) ( 10 14 15 11 ) (14 18 19 15 ) (18 22 23 19 ) (22 26 27 23 ) 54 (26 30 31 27 ) (30 34 35 31 ) (34 38 39 35 ) (38 42 43 39 ) (42 46 47 43 ) (46 50 51 47 ) (50 54 55 51 ) (54 58 59 55 ) (58 62 63 59 ) (62 66 67 63 ) (66 70 71 67 ) (70 74 75 71 ) (74 78 79 75 ) (78 82 83 79 ) (82 86 87 83 ) (86 90 91 87 ) ); } heatWall2 { type wall; faces ( (0123) (1892) ( 12 13 ) (12 16 17 13 ) (16 20 21 17 ) (20 24 25 21 ) (24 28 29 25 ) (28 32 33 29 ) (32 36 37 33 ) (36 40 41 37 ) (40 44 45 41 ) (44 48 49 45 ) (48 52 53 49 ) (52 56 57 53 ) (56 60 61 57 ) (60 64 65 61 ) (64 68 69 65 ) (68 72 73 69 ) (72 76 77 73 ) (76 80 81 77 ) (80 84 85 81 ) (84 88 89 85 ) ); } top { type wall; separationVector (0 0); faces ( (3267) ( 11 ) 55 ( 13 15 11 ) (13 17 19 15 ) (17 21 23 19 ) (21 25 27 23 ) (25 29 31 27 ) (29 33 35 31 ) (33 37 39 35 ) (37 41 43 39 ) (41 45 47 43 ) (45 49 51 47 ) (49 53 55 51 ) (53 57 59 55 ) (57 61 63 59 ) (61 65 67 63 ) (65 69 71 67 ) (69 73 75 71 ) (73 77 79 75 ) (77 81 83 79 ) (81 85 87 83 ) (85 89 91 87 ) ); } bot { type wall; separationVector (0 0); faces ( (0154) ( 10 ) ( 12 14 10 ) (12 16 18 14 ) (16 20 22 18 ) (20 24 26 22 ) (24 28 30 26 ) (28 32 34 30 ) (32 36 38 34 ) (36 40 42 38 ) (40 44 46 42 ) (44 48 50 46 ) (48 52 54 50 ) (52 56 58 54 ) (56 60 62 58 ) (60 64 66 62 ) (64 68 70 66 ) (68 72 74 70 ) (72 76 78 74 ) (76 80 82 78 ) (80 84 86 82 ) (84 88 90 86 ) ); } entrance { type wall; faces ( ( 92 94 ) 56 ( 94 95) ( 93 95) ( 92 93 ) ); } tail { type wall; faces ( ( 88 96 98 90 ) ( 88 96 97 89) ( 90 98 99 91) ( 89 97 99 91 ) ); } ); A2 Turbulence properties code /* *- C++ -* *\ ========= | \\ / F ield | OpenFOAM: The Open Source CFD Toolbox \\ / O peration | Website: https://openfoam.org \\ / A nd | Version: \\/ M anipulation | \* -*/ FoamFile { version 2.0; format ascii; class dictionary; location "constant"; object turbulenceProperties; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // simulationType LES; LES { LESModel WALE; turbulence on; printCoeffs on; delta cubeRootVol; dynamicKEqnCoeffs { filter simple; } cubeRootVolCoeffs { deltaCoeff 1; } PrandtlCoeffs { delta cubeRootVol; 57 cubeRootVolCoeffs { deltaCoeff 1; } smoothCoeffs { delta cubeRootVol; cubeRootVolCoeffs { deltaCoeff 1; } maxDeltaRatio 1.1; } Cdelta 0.158; } vanDriestCoeffs { delta cubeRootVol; cubeRootVolCoeffs { deltaCoeff 1; } smoothCoeffs { delta cubeRootVol; cubeRootVolCoeffs { deltaCoeff 1; } maxDeltaRatio 1.1; } Aplus Cdelta 26; 0.158; } smoothCoeffs { delta cubeRootVol; cubeRootVolCoeffs { deltaCoeff 1; } maxDeltaRatio 1.1; } } // ************************************************************************* // A3 Discretization Scheme /* *- C++ -* *\ ========= | 58 \\ / F ield | OpenFOAM: The Open Source CFD Toolbox \\ / O peration | Website: https://openfoam.org \\ / A nd | Version: \\/ M anipulation | \* -*/ FoamFile { version 2.0; format ascii; class dictionary; location object "system"; fvSchemes; } // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // ddtSchemes { default backward; } gradSchemes { default Gauss linear; } divSchemes { default div(phi,U) none; Gauss linearUpwind grad(U); 59 div(phi,k) Gauss linearUpwind default; div(phi,s) bounded Gauss limitedLinear 1; div((nuEff*dev2(T(grad(U))))) Gauss linear; div(phi,T) Gauss linearUpwind default; } laplacianSchemes { default Gauss linear corrected; } interpolationSchemes { default linear; } snGradSchemes { default corrected; } // ***************************************************************** ******** // 60 ... Steady flow inside the corrugated channel 16 3.3 The effect of pulsating flow 20 3.4 The effect of amplitude of pulsating flow 28 3.5 The effect of frequency of pulsating flow. .. effect of heat transfer rate Sharp corrugated channel Sinusoidal corrugated channel Rectangular corrugated channel Arc corrugated channel Trapezoidal corrugated channel Figure The distribution of investigated... factor LIST OF TABLES Table Effect of amplitude of pulsating flow 28 Table Effect of frequency of pulsating flow 31 LIST OF FIGURES Figure The distribution of investigated channels’