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研究生:林正民
研究生(外文):Cheng-Min Lin
論文名稱:各種對衝流場之數值模擬與分析
論文名稱(外文):Numerical Simulation and Analysis of a Various Impinging Streams Flow Field
指導教授:莊書豪莊書豪引用關係
指導教授(外文):Shu-Hao Chunag
學位類別:碩士
校院名稱:國立中興大學
系所名稱:機械工程學系
學門:工程學門
學類:機械工程學類
論文種類:學術論文
論文出版年:2003
畢業學年度:91
語文別:中文
論文頁數:119
中文關鍵詞:對衝流場燃燒室橫向流混合效果
外文關鍵詞:opposing streamscombustion chambercrossflowmixing quality
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摘要
本文使用套裝軟體PHOENICS對二維層流或紊流對衝流場的混合效果及流體行為做綜合性的探討與分析。在層流中,直接建立Navier-Stokes方程式,並以控制體積積分法建立有限差分方程式,按SIMPLEST計算程序求解;而在模擬二維、不可壓縮之矩形對衝紊流流場,則採用修正後之Lam— 雙方程式紊流模式,並以控制體積積分法建立有限差分方程式,按SIMPLEST計算程序求解,分別就上下噴口速度比(VR)、噴口中心間距(S)、兩平板距離(H)及橫向流的有無( )等參數變化,分析它們對流場中速度、壓力、溫度及結構的影響。
經所得結果顯示,在無橫向流的對衝流場之下,無論是單噴對衝或是雙噴對衝,紊流所得的混合效果均較層流良好。且當上下噴口速度比愈大時,其所獲得溫度分佈愈均勻,混合狀況愈佳。隨著高度增加,其混合效果逐漸變差。當有橫向流時,其速度愈大,所挾帶動量也愈大,對於對衝流場則有較差的混合效果。
綜合言之,分析對衝流場的混合效果及流場結構,有助於了解空氣和燃油的混合,且更能充分掌握影響燃燒的因子,以提供業界在設計各種燃燒室上的參考。
關鍵字:對衝流揚、燃燒室、橫向流、混合效果
Abstract
In this study, a computational fluid (CFD) code, PHOENICS is used to calculate the flow field of 2-D double impinging streams to make the exploration of the comprehensive about mixing effects and flow behavior in two-dimensional opposed streams. In the laminar flow, directly construct the Navier-Stokes equation, and the control-volume integration formula for finite difference and SIMPLEST algorithm to solute. In the turbulence flow, the Lam correctional k-e two-equation turbulence model and the control-volume integration formula for finite difference and SIMPLEST algorithm are employed to simulate the two-dimensional, incompressible flow field. The velocity ratios (VR) of top jets to bottom jets, the nozzle to nozzle centerline spacing (S), the plate to plate distance (H) and the effect of the crossflow velocity ( ) on the flow field structure will be studied.
From the numerical results, either single group or dual jets without crossflow, turbulent flow is better than laminar flow. When jets velocity ratio became larger, it got more uniform temperature distribution and mixing. But when the height is increasing, mixing quality got worst.
Finally, analyzing mixing effects in the opposing streams and field structures, it would be helpful to understand the mixing of air-fuel ratio. The numerical results could prove industry to design all kinds of combustion chambers.
Key Words:opposing streams, combustion chamber, crossflow, mixing quality
目 錄
中文摘要 Ⅰ
英文摘要 Ⅱ
目 錄 Ⅲ
表 目 錄 Ⅵ
圖 目 錄 VII
符號說明 XVII
第一章 緒論 1
1-1 前言 1
1-2 流場分析 2
1-3 文獻回顧 5
1-4 研究動機與目的 9
第二章 物理模型與統御方程式 11
2-1 物理模型 11
2-2 基本假設 12
2-3 統御方程式 13
2-4 紊流模式 15
2-4-1 標準 與Lam- 模式之統御方程式 15
2-4-2 Lam-Bremhorst- 紊流模式 18
2-5 邊界條件 20
2-6 溫度混合指標 21
第三章 數值方法與求解程序 23
3-1 簡介 23
3-2 交錯式網格點系統 23
3-3 離散方程式的建立 25
3-3-1 差分方程式 25
3-3-2 混合法則 27
3-3-3 離散方程式的建立 31
3-4 求解程序 33
3-4-1 SIMPLE求解法 33
3-4-2 SIMPLE與SIMPLEST求解法之比較 36
3-4-3 鬆弛因子 38
3-4-4 收斂條件 39
3-5 數值模擬流程 40
第四章 結果與討論 42
4-1 前言 42
4-2 流場結構分析 43
4-2-1 單噴對衝 43
4-2-2 雙噴對衝 45
4-3 對衝流場混合效果之分析 50
4-3-1 上下噴射主流速度比對混合效果的影響 50
4-3-2 噴口中心間距對混合效果的影響 51
4-3-2 兩平板距離高度對混合效果的影響 52
4-3-4 橫向流的影響 53
第五章 結論與未來研究方向建議 54
參考文獻 56
附錄A 壁函數的說明 61
附表 65
附圖 69
參考文獻
1.J. C. ROY, C. Bertrand, “Numerical and Experimental Study of Mixed and Forced Convection in a Junction”, Int. J. Heat Mass Transfer, Vol.37, No.14, pp.1985-2006, 1994.
2.T.-M.Liou, S.-M.Wu, Y.-H.Hwang,“Experimental and Theoretial
Investigations of Turbulent Flow in a Side-Inlet Rectangular Combustion”, J. Propul., Vol.6, No.12, pp.131-138, 1990.
3.劉明山,許家隆,「側向噴流對後續燃燒器之流場混合效應數值模擬
分析(A Numerical Investigation of Mixing of the Flow in A
Seqential Burner with Transverse Jets)」,逢甲大學機械工程研
究所碩士論文(1990).
4.Sakamon Devahastin, Arun S. Mujumdar, “A Study of Turbulent Mixing of Confined Impinging Streams Using a New Composite Turbulence Model", Ind. Eng. Chem. Res, Vol. 40, pp.4998-
5004, 2001.
5.Sakamon Devahastin, Arun S. Mujumdar, “A Numerical Study of Flow and Mixing Characteristics of Laminar Confined Impinging
Stream”, Chemical Engineering Journal, Vol. 85, pp.215-223,
2002.
6.Sakamon Devahastin, Arun S. Mujumdar, “A Numerical Study of
Mixing in a Novel Impinging Stream in-Line Mixer”, Chemical
Engineering Journal, Vol. 40, pp.459-470, 2001.
7.Y. R. Chang, K. S. Chen, “Prediction of Opposing Turbulent Line Jets Discharged Laterally into a Confined Crossflow”, Int. J. Heat Mass Transfer, Vol. 38, No. 9, pp.1693-1703, 1995.
8.Y. R. Chang, K. S. Chen, “Measurement of Opposing Heated Line Jets Discharged at an Angle to a Confined Crossflow”, Int. J. Heat Transfer, Vol. 37, No. 18, pp.2935-2946, 1994.
9.K. S. Chen, J. Y. Hwang, “Experimental Study on the Mixing of One- and and Dual-Line Heated Jets with a Cold Crossflow in a Confined Channel”, AIAA Journal, Vol. 29, No. 3, pp.353-360,
1991.
10.N. Chinzei, G. Masuya, S. Ishii, K. Kudo, A. Murakami, T.
Komuro,“A Study of Air Breathing Rockets(I)―Pressure Distribution and Combustion Performances of Subsonic Cylindrical Secondary Combustions”, Nat. Aerospace Lab. REP., NAL TR-573(in Japanese), 1979.
11.A. Murakami, T. Kudou, G. Masuya, N. Chinzei, “A Study of Breathing Rochets(IV) ─Direct Fuel Injection into a Secondary Combustion”, NTIS Report#N85-18083/4/XAB
(in Japanease), 1984.
12.邱耀平,「噴流在一受限橫向流場之衝擊過程特性研究」,力學會刊,
pp.141-151, 1997.
13.Z.A. Khan,J.H. Whitelaw,“Vector and Scalar Characteristics
of Opposed Jets Discharging Normally into A Cross Stream”,
Int. J. Heat Mass Transfer, Vol. 23, pp.1443-1980.
14.M.J. Siclari, W.G.Hill, R.C. Jenkins, “Stagnation Line and
Upwash Formation of Two Impinging Jets”,AIAA Journal, Vo1.
19, No. 10, pp.1286-1293, 1981.
15.K. N. Atkinson, Z. A. Khan, J.H. Whitelaw, “Experimental
Investigation of Opposed Jets Discharging Normally into A
Cross-Stream”,J. Fluid Mechanics, Vol. 115, pp.493-504, 1982.
16.J. D. Holdman, R. Srinivasan, A. Berenfeld, “Experimentalin
Dilution JET Mixing”, AIAA Journal, Vol. 21, No. 10, pp.1436-
1443, 1984.
17.R. E. Breidenthal, K.O. Tang, G.S. Wang, R.D. Hamerquist, P.
B. Landry, ”Turbulent Mixing in Two-Dimensional Ducts with
Transverse Jets”, AIAA Journal, Vol.24, No. 11, pp.1867-1869,
1986.
18.C. Shin and S. Gogineni, “Experimental Study of Perturbed
Laminar Wall Jet”, AIAA Journal, Vol. 33, No. 3, pp.559-561,
1994.
19.W. W. Bower, D. R. Kotansky, “A Navier-Stokes Analysis of the
Two-Dimentional Ground Effects Problem”, AIAA paper, pp.576-
621, July 1996.
20.D. R. Kotansky, W. W. Bower, “A Basic Study of the VTOL Ground
Effect Problem for Planar Flow”, J. Aircraft, Vol. 15, No. 4,
pp.214-221, Apr. 1978.
21.王俊琪與李聰盛,「燃燒室內流體混合之研究」,中國航空太空學會
年刊, pp.25-32, 1985.
22.莊書豪,張義鋒,魏清源,「噴射撞擊流之數值模擬與分析(Numerical
Simulation and Analysis of Impinging Jet)」,中原大學機械工
程研究所碩士論文(1990).
23.莊書豪,黃仁智,陳明華,「二維雙噴射撞擊流之數值模與分析
(Numerical Simulation of Two-Dimentional Impinging Twin-
Jet on a Ground Surface)」,逢甲大學機械工程研究所論文
(1990).
24.吳念祖,「駐焰器與側進冷卻突張式燃燒室漩渦流場效應分析」,逢
甲大學機械工程研究所論文(1991).
25.S. W. Kim, T. J. Benson, “Fluid Flow of Jets in Crossflow A
Numerical Study”, AIAA Journal, Vol. 31, No. 5, pp.806-811,
May. 1993.
26.Jorge M.M. Barata, ”Foutain Flow Produced by Multiple Impinging Jets
in a Crossflow”, AIAA Journal, Vol. 34, No. 12, pp.2523-2530,
December 1996.
27. B. E. Launder, D. B. Spalding, “The Numerical Computation of
Turbulent Flow”, Computer Methods in Applied Mechanics and
Engineering, Vol. 3, pp.269-289, 1974.
28.C. K. G. Lam, K. Bremhorst,“A Modified Form of the Model
Model for Predicting Wall Turbulence”, ASME J. of Fluids
Engineering, Vol. 103, pp.456-460, 1981.
29.Concentration, Heat and Momentum Limited (CHAM), POLIS:
Phoenics On-Line Information System, London, 1997,http://
www.cham.co.uk.
30.Keh-Chin Chang, Ching-Shun Chen, “Development of A Hybrid
Turbulence Model for Swirling Recirculating Flows Under Moderate to Strong Swirl Intensities” Int. Journal for Numerical Methods in Fluids, Vol. 16, pp. 421-443, 1993.
31. S. V. Patankar, D. B. Spalding, “A Calculation Procedure for Heat, Mass and Momentum Transfer in Three-Dimensional Parabolic Flows”, Int. J. Heat Transfer, Vol. 15, pp. 1787-1806, 1972.
32. S. V. Patankar, “Numerical Heat Transfer and Fluid Flow”, Hemisphere Publishing Co., New York, 1980.
33. S.V. Patankar, “A Calculation Procedure for Two-Dimensional Elliptic Situations”, Numerical Heat Transfer, Vol. 4., pp. 409-425, 1981.
34.趙勝裕, 黃榮鑑, “ 紊流模式近壁行為之探討”, 力學,Vol. 13, No.3, pp.265-275, 1997.
35.Virendra C. Patel, Wolfgang Rodi, Georg Scheuerer, Turbulence Models for Near-Wall and Low Reynolds Number Flows: A Review”, AIAA Journal, Vol.23, No. 9, pp. 1308-1319, 1985.
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