本研究係以數值模擬的方式，探討不同進回風口位置對實驗室內污染物被排除的效果及氣流狀態之影響，與微塵粒徑大小受重力效應影響下在實驗室中的抑制效果、排除效果、淨空時間、與各出風口的排除比例。前者使用之統御方程式包括連續方程式、動量方程式、能量方程式與粒子運動方程式，其紊流模式採用標準 紊流模式，統御方程式之對流項採用upwind方法解離；後者利用拉格朗日粒子軌跡追蹤法與CFD模擬研究。分析結果顯示：當進風口置於靠近門處，可防止污染物大量進入實驗室內，卻無法有效的將原存於實驗室內之污染粒子排除；若進風口置於實驗室中間，雖無法有效抑制污染粒子進入，但可將汙染粒子帶至各角落之排風口予以排除；倘進風口遠離門處，則對污染粒子不論是抑制或排除效果皆不理想。另外，送風口位置對不同粒徑大小之微塵粒子的抑制率與移除率的研究結果顯示：送風口以最靠近門處的抑制率為最高，以房間正中央處的排除效果為最好，且送風口位置離門愈遠，其抑制與排除效果有越不明顯的趨勢。後續找出最適當之送風口位置後，繼續對不同粒徑大小之粒子進行分析，結果顯示：粒徑愈大，受重力效應之影響則愈大，較快沉澱到地面上而經由排風口排除，反之則容易受氣流所帶動漂浮在半空中。另外，抑制率與排除率因粒徑大小而有明顯之趨勢。

The efficiency of restraining particles and particle removal from laboratory, installed air supply and air exhaust in various positions were investigated by numerical method to simulate the flow conditions, accompanied by a Lagrangian particle-tracking method to calculate the trajectories of the particles in the laboratory. Three cases with air supplied from different locations in the laboratory were used to investigate the restraint and removal effects in the study. The equation of continuity, momentum equation, energy equation and particle’s equation of motion are considered in governing equation. model is adopted in Turbulence Models. The convection term of governing equation is used upwind method to solve, then, Lagrangian particle-tracking method and CFD simulation method is introduced to simulate all conditions. The analysis results indicate that when air supply is located on the ceiling near the door, the efficiency of restraining particles from entrance of the laboratory is the best of these three cases. Nevertheless, the existing particle removal efficiency of this case can not remove contaminated particles effectively. Although the contaminated particles can not be removed effectively, but they cannot be spread out in laboratory when the air supply is located in the ceiling center of laboratory. If the air supply is located in the distant place of laboratory, the inhibition and elimination efficiency of the contaminated particles are not obvious. Otherwise, the analysis results of the inhibition and elimination efficiency of the contaminated particles the different outlet positions in proportion to various diameters of particles reveal that the inhibition efficiency of the contaminated particles is the best when outlet is located in the entrance of laboratory and the elimination efficiency of the contaminated particles is the best when outlet is located in the center ceiling of laboratory. Then, the analysis results of the inhibition and elimination efficiency of the various contaminated particles indicate that the bigger diameters of particles are affected by the more gravity, when they settle to ground, they will be discharged by outlet. Contrarily, the smaller particles are easily affected by airflow to float in mid air. The inhibition and elimination efficiency of the various contaminated particles are obviously influenced by size of particles.

第一章　緒論 1
　1.1　前言 1
　1.2　文獻回顧 1
　1.3　研究目的 2
第二章　物理模式 3
　2.1　物理模型 3
　2.2　物理模型使用之假設 4
　2.3　邊界條件 4
第三章　數值方法 7
　3.1　數值方法 7
　3.2　網格建立 7
第四章　結果與討論 8
　4.1　進風口靠近門(case1) 10
　4.2　進風口位於中間(case2) 23
　4.3　進風口遠離門(case3) 38
4.4 不同粒徑粒子的流動狀態 42
4.5 不同粒徑大小粒子，對抑制率的影響 43
4.6 不同粒徑大小粒子，對移除率的影響 45
4.7 各個排風口的移除率 46
第五章　結論 50
參考文獻 52

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