臺灣博碩士論文加值系統

本篇論文利用實驗流場觀測方法及溫度場量測方法探討在較大的噴流到圓盤的距離對於在垂直圓柱容器中一空氣圓形噴流衝擊至一加熱圓盤的穩態及非穏態渦流結構之流場特性進行研究。由於在較大的高度下，慣性力及浮力所驅動的渦流相對的比較強烈，所以本實驗主要的研究重點是在探討噴流到圓盤的距離對於穩態及非穏態的慣性力及浮力渦流結構流場之臨界發生點與特徵，除此之外，由慣性力及浮力所造成的非穏態流場也將會註明。在本實驗研究操作範圍分別是：噴流到圓盤的距離40〜60 mm，噴流的直徑固定為10 mm，流量變化0〜12.0 slpm，加熱圓盤與入口冷空氣間的溫度差範圍0〜25.0℃，所相對的噴流雷諾數變化為0〜1,623，相對於雷利數0〜507,348。
由流場觀測及溫度場量測可以清楚顯示噴流到圓盤的距離對於一次渦流、二次渦流、三次渦流及浮力渦流的臨界發生雷諾數有顯著的影響。其中一次渦流
只有在噴流到圓盤的距離比上噴流的直徑HDj為6且非常高的浮慣比之下會消失，而二次流在HDj為5及6下不會出現。
除此之外，我們定義了四種典型的不穩定現象，分別是慣性力、渦流相互推擠、第一類浮力、第二類浮力所造成的不穩定渦流流場，其中第二類浮力所造成的不穩定渦流流場發生在HDj等於4到6且非常低的雷諾數下。而在HDj等於4時流譜主要是由渦流相互推擠這種不穩定渦流流場所主導，而當HDj由4增加到6時，流譜則漸漸轉由非週期性的慣性力所造成的不穩定渦流流場主導。除此之外，當HDj增加時，流譜中的穩定渦流流場區域逐漸縮小。
最後，我們對由慣性力及浮力所造成的渦流及各類的渦流流場不穩定性的實驗結果做分析，求得經驗公式。

ABSTRACT i
TABLE OF CONTENTS iii
LIST OF TABLES v
LIST OF FIGURES vi
NOMENCLATURE xiv
CHAPTER 1 INTRODUCTION 1
1.1 Motivation 1
1.2 Literature Review 2
1.3 Objective and Scope of Present Study 6
CHAPTER 2 EXPERIMENTAL APPARATUS AND
PROCEDURES 8
2.1 Experimental Apparatus 8
2.2 Experimental Procedures 11
CHAPTER 3 DIMENSIONLESS GROUPS AND
UNCERTAINTY ANALYSIS 16
3.1 Dimensionless Groups 16
3.2 Uncertainty Analysis 16
CHAPTER 4 RESULTS AND DISCUSSION 20
4.1 Typical Vortex Flow Patterns 21
4.2 Effects of HDj on Onsets of Inertia and Buoyancy
Driven Vortex Rolls 23
4.3 Effects of HDj on Steady Vortex Flow
Characteristics 28
4.4 Effects of HDj on Vortex Flow Instabilities 30
4.5 Effects of HDj on Time-Dependent Vortex Flow
Characteristics 38
CHAPTER 5 CONCLUDING REMARKS 161
REFERECES 164

1. Frnank. P. Incropera, Liquid cooling of electronic devices by single-phase convection, John Wiley & Sons, Inc, New York, 1999 (chapter 2).
2. K. Jambunathan, E. Lai, M. A. Moss and B. L. Button, A review of heat transfer data for single circular jet impingement, International Journal of Heat and Fluid Flow 13 (1992) 106-115.
3. R. Viskanta, Heat transfer to impinging isothermal gas and flame jets, Experimental Thermal and Fluid Science 6 (1993) 111-134.
4. Z. H. Lin, Y. J. Chou and Y. H. Hung, Heat transfer behaviors of a confined slot jet impingement, International Journal of Heat and Mass Transfer 40 (1997) 1095-1107.
5. J. A. Fitzgerald and S. V. Garimella, A study of the flow field of a confined and submerged impinging jet, International Journal of Heat and Mass Transfer 41 (1998) 1025-1034.
6. G. K. Morris, and S.V. Garimella, Orifice and impingement flow fields in confined jet impingement, J. Electronic Packaging 120 (1998) 68-72.
7. G. K. Morris, S. V. Garimella and J. A. Fitizgerald, Flow-field prediction in submerged and confined jet impingement using the Reynolds Stress Model, J. Electronic Packaging 121 (1999) 255-262.
8. D. W. Colucci and R. Viskanta, Effect of nozzle geometry on local convective heat transfer to a confined impinging air jet, Experimental Thermal and Fluid Science 13 (1996) 71-80.
9. N. Gao and D. Ewing, Investigation of the effect of confinement on the heat transfer to round impinging jets existing a lone pipe, International J. Heat and Fluid Flow 27 (2006) 33-41.
10. V. Narayanan, J. Seyed – Yagoobi, and R. H. Page, An experimental study of fluid mechanics and heat transfer in an impinging slot jet flow, International Journal of Heat and Mass Transfer 47 (2004) 1827-1845.
11. M. Angioletti, R. M. Di Tommaso, E. Nino, and G. Ruocco, Simultaneous visualization of flow field and evaluation of local heat transfer by transitional impinging jets, International Journal of Heat and Mass Transfer 46 (2003) 1703-1713.
12. T. H. Park, H. G. Choi, J. Y. Yoo and S. J. Kim, Streamline upwind numerical simulation of two-dimensional confined impinging slot jets, International Journal of Heat and Mass Transfer 46 (2003) 251-262.
13. J. C. Hsieh, T. C. Cheng and T. F. Lin, Characteristics of vortex flow in a low speed air jet impinging onto a heated disk in a vertical cylindrical chamber, International Journal of Heat and Mass Transfer 46 (2003) 4639-4656.
14. H. S. Law and J. H. Masliyah, Mass transfer due to a confined laminar impinging axisymmetric jet, Int. Eng. Chem. Fundam. 23 (1984) 446-454.
15. D. Sahoo and M. A. R. Sharif, Numerical modeling of slot-jet impingement cooling of a constant heat flux surface confined by a parallel wall, International Journal of Thermal Sciences 43 (2004) 877-887.
16. J. C. Hsieh and T. F. Lin, Effects of jet-to-disk separation distance on the characteristics of mixed convective vortex flow in an impinging air jet confined in a cylindrical chamber, International Journal of Heat and Mass Transfer 48 (2005) 511-525.
17. V. A. Chiriac and A. Ortega, A numerical study of the unsteady flow and heat transfer in a transitional confined slot jet impinging on an isothermal surface, International Journal of Heat and Mass Transfer 45 (2002) 1237-1248.
18. H. V. Santen, C. R. Kleijn and H. E. A. Van Den Akker, Mixed convection in radial flow between horizontal plates- І. Numerical simulations, International Journal of Heat and Mass Transfer 43 (2000) 1523-1535.
19. H. V. Santen, C. R. Kleijn and H. E. A. Van Den Akker, Mixed convection in radial flow between horizontal plates- ΙΙ. Experiments, International Journal of Heat and Mass Transfer 43 (2000) 1537-1546.
20. Y. M. Chung and K. H. Luo, Unsteady heat transfer analysis of an impinging jet, ASME Transac. C, J. Heat Transfer 124 (2002) 1039-1048.
21. H. J. Poh, K. Kumar, and A. S. Mujumdar, Heat transfer from a pulsed laminar impinging jet, International Communicatios in Heat and Mass Transfer 32 (2005) 1317-1324.
22. J. C. Hsieh, C. W. Cheng and T. F. Lin, Suppression of buoyancy-driven vortex flow resulting from a low speed jet impinging onto a heated disk in a vertical cylinder by cylinder top tilting, International Journal of Heat and Mass Transfer 47 (2004) 3031-3045.
23. H. S. Law and J. H. Masliyah, Numerical prediction of the flow field due to a confined laminar two-dimensional submerged jet, Computers & Fluids 12 (1984) 199-215.
24. P. Y. Lin, Transient liquid crystal measurement of local heat transfer in a low air speed air jet impinging onto a disk in a vertical cylindrical chamber, M. S.thesis. National Sun Yat-sen University, Kaohsiung, Taiwan, R. O. C., 2004.
25. Y. J. Chou and Y. H. Hung, Impinging cooling of an isothermally heated surface with a confined slot jet, J. Heat Transfer 116 (1994) 479-482.
26. F. C. Hsieh, J.H. Wu, J. C. Hsieh and T. F. Lin, Unstable Vortex Flow and New Inertia-Driven Vortex Rolls Resulting from an Air Jet Impinging onto a Confined Heated Horizontal Disk, International Journal of Heat and Mass Transfer 49 (2006) 4697-4711.
27. G. Wahl, Hydrodynamic description of CVD processes, Thin Solid Films 40 (1977) 13-26.
28. D. I. Fotiadis and S. Kieda, Transport phenomena in vertical reactor for metalorganic vapor phase epitaxy, J. Crystal Growth 102 (1990) 441-470.
29. A. H. Dilawari and J. Szekely, A mathematical representation of a modified stagnation flow reactor for MOCVD application, J. Crystal Growth 108 (1991) 491-498.
30. C. Y. Soong, Gasdynamic characteristics and thermal-flow design of metal organic chemical vapor deposition reactors for semiconductor thin-films, Instruments Today, 25(3), (1993) 71-82.
31. H. V. Santen, C. R. Kleijn and H. E. A. Van Den Akker, Symmetry breaking in a stagnation-flow CVD reactor, J. Crystal Growth 212 (2000) 311-323.
32. S. P Vanka, G. Luo, and N. G. Glumac, Parametric effects on thin film growth and uniformity in an atmospheric pressure impinging jet CVD reactor, J. Crystal Growth 267 (2004) 22-34.
33. G. Luo, S. P. Vanka, and N. Glumac, Fluid flow and transport processes in a large area atmospheric pressure stagnation flow CVD reactor for deposition of thin films, International Journal of Heat and Mass Transfer 47 (2004) 4979-4994.
34. W. Burwash, W. Finlay, and E. Matida, Deposition of particles by a confined impinging jet onto a flat surface ar Re = 104, Aerosol Science and Technology 40 (2006) 147-156.
35. S. J. Kline and F. A. Mcclintock, Describing Uncertainties in Single-Sample Experiment, Mechanical Engineering 75 (1953) 3-8.
36. R. J. Moffat, Contributions to the Theory of Single-Sample Uncertainty Analysis, ASME Transac, J. Fluids Engineering 104 (1982) 250-260.
37. Thermophysical Properties of Fluid, JSME Data Book (1983)