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完整後設資料紀錄
DC 欄位 | 值 | 語言 |
---|---|---|
dc.contributor.advisor | 周逸儒(Yi-Ju Chou) | |
dc.contributor.author | Yen-Cheng Chang | en |
dc.contributor.author | 張晏誠 | zh_TW |
dc.date.accessioned | 2021-06-17T01:23:24Z | - |
dc.date.available | 2017-10-01 | |
dc.date.copyright | 2017-08-11 | |
dc.date.issued | 2017 | |
dc.date.submitted | 2017-08-09 | |
dc.identifier.citation | [1] Acrivos, A. and E. Herbolzheimer (1979). 'Enhanced sedimentation in settling tanks with inclined walls.' Journal of Fluid Mechanics 92(03): 435-457.
[2] Andrews, M. and P. O'Rourke (1996). 'The multiphase particle-in-cell (MP-PIC) method for dense particulate flows.' International Journal of Multiphase Flow 22(2): 379-402. [3] Auton, T., et al. (1988). 'The force exerted on a body in inviscid unsteady non-uniform rotational flow.' Journal of Fluid Mechanics 197: 241-257. [4] Berryman, J. G. (1983). 'Random close packing of hard spheres and disks.' Physical Review A 27(2): 1053. [5] Boycott, A. (1920). 'Sedimentation of blood corpuscles.' Nature 104(2621): 532-532. [6] Chorin, A. J. (1967). 'The numerical solution of the Navier-Stokes equations for an incompressible fluid.' Bulletin of the American Mathematical Society 73(6): 928-931. [7] Chou, Y.-J., et al. (2015). 'An Euler–Lagrange model for simulating fine particle suspension in liquid flows.' Journal of Computational Physics 299: 955-973. [8] Chou, Y.-J. and Y.-C. Shao (2016). 'Numerical study of particle-induced Rayleigh-Taylor instability: Effects of particle settling and entrainment.' Physics of Fluids 28(4): 043302. [9] Cui, A. (1999). On the parallel computation of turbulent rotating stratified flows, Stanford University. [10] Cundall, P. A. and O. D. Strack (1979). 'A discrete numerical model for granular assemblies.' geotechnique 29(1): 47-65. [11] Duran, J. and T. Mazozi (1999). 'Granular boycott effect: How to mix granulates.' Physical Review E 60(5): 6199. [12] Gibilaro, L., et al. (1985). 'Generalized friction factor and drag coefficient correlations for fluid-particle interactions.' Chemical Engineering Science 40(10): 1817-1823. [13] Gidaspow, D. (1994). Multiphase flow and fluidization: continuum and kinetic theory descriptions, Academic press. [14] Graham, W. and R. Lama (1963). 'Continuous thickening in an inclined thickener.' The Canadian Journal of Chemical Engineering 41(4): 162-165. [15] Herbolzheimer, E. (1983). 'Stability of the flow during sedimentation in inclined channels.' Physics of Fluids 26(8): 2043-2054. [16] Herbolzheimer, E. and A. Acrivos (1981). 'Enhanced sedimentation in narrow tilted channels.' Journal of Fluid Mechanics 108: 485-499. [17] Hill, W. D., et al. (1977). 'Boundary-enhanced sedimentation due to settling convection.' International Journal of Multiphase Flow 3(6): 561-583. [18] Hoomans, B. P. B. (2000). Granular dynamics of gas-solid two-phase flows, Universiteit Twente. [19] Hoomans, B. P. B., et al. (1996). 'Discrete particle simulation of bubble and slug formation in a two-dimensional gas-fluidised bed: A hard-sphere approach.' Chemical Engineering Science 51(01): 99-118. [20] Kaushal, D., et al. (2012). 'CFD modeling for pipeline flow of fine particles at high concentration.' International Journal of Multiphase Flow 43: 85-100. [21] Kinosita, K. (1949). 'Sedimentation in tilted vessels (1).' Journal of Colloid Science 4(5): 525-536. [22] Lundgren, R. (1927). 'A study of the physical nature of the sedimentation of blood‐corpuscles.' Journal of Internal Medicine 67(1): 63-104. [23] Nakamura, H. and K. Kuroda (1937). 'La cause de l’acceleration de la vitesse de sedimentation des suspensions dans les recipients inclines.' Keijo J. Med 8: 256-296. [24] Patankar, N. and D. Joseph (2001). 'Lagrangian numerical simulation of particulate flows.' International Journal of Multiphase Flow 27(10): 1685-1706. [25] Patankar, N. and D. Joseph (2001). 'Modeling and numerical simulation of particulate flows by the Eulerian–Lagrangian approach.' International Journal of Multiphase Flow 27(10): 1659-1684. [26] Pearce, K. (1962). Settling in the presence of downward-facing surfaces. Proceedings of the Symposium on the Interaction between Fluids and Particles, London. [27] Ponder, E. (1925). 'On sedimentation and rouleaux formation.' Experimental Physiology 15(3): 235-252. [28] Richardson, J. and W. Zaki (1954). 'The sedimentation of a suspension of uniform spheres under conditions of viscous flow.' Chemical Engineering Science 3(2): 65-73. [29] Snider, D., et al. (1998). 'Sediment flow in inclined vessels calculated using a multiphase particle-in-cell model for dense particle flows.' International Journal of Multiphase Flow 24(8): 1359-1382. [30] van der Hoef, M. A., et al. (2006). 'Multiscale modeling of gas-fluidized beds.' Advances in chemical engineering 31: 65-149. [31] Vohra, D. and B. Ghosh (1971). 'Studies of sedimentation in inclined tubes.' Indust. Engng Chem 13: 3240. [32] Xu, Z.-J. and E. E. Michaelides (2005). 'A numerical simulation of the Boycott effect.' Chem. Eng. Comm. 192(4): 532-549. [33] Zahavi, E. and E. Rubin (1975). 'Settling of solid suspensions under and between inclined surfaces.' Industrial & Engineering Chemistry Process Design and Development 14(1): 34-41. [34] Zhang, D. and A. Prosperetti (1997). 'Momentum and energy equations for disperse two-phase flows and their closure for dilute suspensions.' International Journal of Multiphase Flow 23(3): 425-453. [35] 古詩弘 (2014). '固液二相懸浮微粒問題之雙向耦合數值模式.' 臺灣大學應用力學研究所學位論文. | |
dc.identifier.uri | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/67203 | - |
dc.description.abstract | 本研究使用雙向耦合之固液二相流Eulerian-Lagrangian三維數值模式,對於Boycott effect問題進行模擬與探討。在Eulerian-Lagrangian模式中,流體相以尤拉描述法在尤拉網格解析Navier-Stokes方程式,固體相則以拉格朗日描述法追蹤每顆顆粒的運動。為了模擬顆粒在邊界的堆積,本模式引入了新的碰撞模型,使顆粒在此碰撞機制下達到隨機緊密堆積。而原本的史托克阻力模型已不再適用於此高濃度流場,故本研究參考其他阻力模型,考慮流場中的顆粒濃度,進行阻力係數修正,建立本模式模擬高濃度流場之能力。
本文以Boycott effect物理問題作為範例,將容器與垂直軸傾斜一角度,模擬顆粒在傾斜容器中加速沉降現象,並以PNK theory驗證其準確性,其模擬結果非常接近理論值。接著改變不同容器傾角,觀察沉降過程中之克耳文-亥姆霍茲不穩定性(Kelvin-Helmholtz instability),且發現此界面不穩定性的形成與容器內清水層厚度有很大的關係,清水層厚度愈大,沉降過程愈穩定,反之愈容易發生不穩定性。最後改變顆粒的直徑與流場初始濃度,分析在不同的參數設定下的顆粒沉降效率,當粒徑愈大,不穩定性的影響愈弱,沉降效率愈好;當初始濃度較低時,也有類似的效果。然而,比較容器傾角、顆粒直徑、流場初始濃度三個參數之影響,改變容器傾角與顆粒直徑的效果優於改變流場初始濃度。模擬結果顯示Boycott effect的確可有效加速顆粒沉降,說明傾斜板或傾斜容器對於顆粒沉降的重要性。 | zh_TW |
dc.description.abstract | This article presents a three dimensional Eulerian-Lagrangian model to simulate the enhanced sedimentation in an inclined vessel which called Boycott effect. The model solves the governing equation of fluid phase on the Eulerian mesh and calculate the motion of Lagrangian particles by Newton’s second law. In order to simulate the depositing particles at the wall, a soft-sphere collisional method is introduced so that the volume fraction reaches a random closed packing limit by the collisional mechanism. Additionally, Stokes’ drag, the previous drag model, is unsuitable for the denser suspension. A drag reduction model that considering the concentration of the fluid is employed. Ultimately, the two-phase model is capable of calculating the motion of fluid and particles in the dense flow.
This model is then used to study the Boycott effect. The result is validated against the PNK theory and agrees well with the theoretical values. The Kelvin-Helmholtz instability is observed during the settling process at different tilted angles. We find that the instability on the interface is related to the thickness of clear fluid layer. The greater the thickness of the clear fluid layer, the more stable the settling process is. Finally, the present work simulate under different parameters such as the diameter of the particles and the initial concentration of the flow field. While the diameter of particles are larger, the instability is weaker, and it leads to the better sedimentation efficiency. It also results in the same performance while setting the less concentration in the initial flow field. However, the effect of the tilted angle and the diameter of particles is more sensitive than the initial concentration. The simulation results show that Boycott effect does enhance the sedimentation in the inclined vessel or under tilted plates. | en |
dc.description.provenance | Made available in DSpace on 2021-06-17T01:23:24Z (GMT). No. of bitstreams: 1 ntu-106-R04543077-1.pdf: 6837432 bytes, checksum: f726d7146cb4f44c78dd765b281aa70f (MD5) Previous issue date: 2017 | en |
dc.description.tableofcontents | 口試委員會審定書 #
誌謝 i 中文摘要 ii ABSTRACT iii 目錄 iv 圖目錄 vi 表目錄 viii Chapter 1 緒論 1 1.1 研究背景 1 1.2 文獻回顧 2 1.3 研究動機 9 1.4 本文內容概述 10 Chapter 2 理論與方法 11 2.1 統御方程式 12 2.1.1 動量方程式 12 2.1.2 連續方程式 13 2.2 顆粒傳輸系統 14 2.3 離散粒子模型(Discrete particle model) 15 2.3.1 硬球模型(Hard-sphere model) 16 2.3.2 軟球模型(Soft-sphere model) 19 2.4 阻力模型 24 2.5 研究方法 25 Chapter 3 數值模式之驗證-顆粒堆積 27 3.1 模擬配置 27 3.2 結果 29 Chapter 4 數值實驗配置 33 4.1 流場模擬配置 34 4.2 顆粒模擬配置 36 Chapter 5 結果與討論 37 5.1 傾斜容器所引起之顆粒加速沉降-Boycott effect 37 5.2 界面不穩定性 47 5.3 顆粒粒徑之影響 59 5.4 初始濃度之影響 67 Chapter 6 結論與未來工作 76 6.1 結論 76 6.2 未來工作 77 REFERENCE 1 | |
dc.language.iso | zh-TW | |
dc.title | 傾斜容器內顆粒加速沉降之數值研究 | zh_TW |
dc.title | Numerical simulation of enhanced sedimentation in an inclined vessel | en |
dc.type | Thesis | |
dc.date.schoolyear | 105-2 | |
dc.description.degree | 碩士 | |
dc.contributor.oralexamcommittee | 牛仰堯(Yang-Yao Niu),曾建洲(Chien-Chou Tseng) | |
dc.subject.keyword | 固液二相流,Boycott effect,克耳文-亥姆霍茲不穩定性, | zh_TW |
dc.subject.keyword | Solid-liquid two-phase flow,Boycott effect,Kelvin-Helmholtz instability, | en |
dc.relation.page | 80 | |
dc.identifier.doi | 10.6342/NTU201702802 | |
dc.rights.note | 有償授權 | |
dc.date.accepted | 2017-08-09 | |
dc.contributor.author-college | 工學院 | zh_TW |
dc.contributor.author-dept | 應用力學研究所 | zh_TW |
顯示於系所單位: | 應用力學研究所 |
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