# 臺灣博碩士論文加值系統

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 膀胱出口阻塞症狀（ＢＯＯ）是一種常見的老年疾病，而現今在臨床上的診斷依據卻又都是用非侵入式的檢測方式，這不僅影響病人的身心健康，還會有感染傳染病的危險。因此，本文的目的是希望能夠利用數值方法發展一套非侵入式的診斷方法來協助醫師診斷膀胱出口阻塞症狀。 本文的研究方法，著重在找出尿道流場中影響壓力損失的最主要因素，我們先建立起尿道的計算網格，利用計算流體力學算出尿道內的流場，壓力分布，在配以實驗驗證我們的數值結果，最後利用這些結果找出一個無因次參數圖來診斷膀胱出口阻塞症狀。 在數值方法上，我們是採用三維的非正交（non-orthogonal）非交錯的網格來處理複雜的幾何外型，並且採用Hybrid的方法來解我們的流場，在壓力修正項方面，我們是採用Simple的方法來避開棋盤狀的速度場和壓力場，另外再以 紊流模式配合壁面函數做為紊流流場的計算。 實驗上，我們模擬了一個五倍大的尿道模型，並配以不同阻塞程度，阻塞外型來做實驗，並以計算流體力學驗證之。 根據我們計算和實驗的結果，我們得知在沒有阻塞的尿道流場內，摩擦損失（Major loss）是影響壓力損失最主要的因素；而在輕微阻塞的尿道流場內，磨差損失（Major loss）及阻塞段幾何外型改變，面積改變的能量損失（Minor loss）都影響很大；而在較為嚴重的阻塞情況下，阻塞段的外型，最小截面積等影響能量損失甚為巨大，另外我們根據計算的結果發展出一個無因次參數圖，我們選用了Reynolds number和 來做參數，結果發現這樣不僅可以把阻塞和未阻塞的病例分清，甚至能判斷逼尿肌無力等症狀。
 In the present study, the aim is to develop a non-invasive measurement technique to diagnose patients having Bladder Outlet Obstruction(BOO). This is achieved by identifying major causes of the pressure loss in the lower urinary system by experimental and CFD methods. Computational fluid dynamics is used to compute the pressure distribution within the urinary system to determine the bladder pressure. This will help to diagnose the symptom of BOO. It is found that the pressure loss in the unobstructed case is due to the presence of friction. For slightly obstructed cases, the pressure losses are due to both the major (frictional) loss and the minor loss due to the change of geometry in the obstructed zone. As for the highly obstructed cases, the large proportion of the pressure loss is the minor loss resulting from the change of the geometry in the obstructed zone. A new set of dimensionless nomogram characterized by two parameters and Reynolds number is used to improve the deficiency of the AG number. Based on the newly proposed nomograph, patients both with obstructed and unobstructed cases can be diagnosed accurately. Also, those patients with weak detrusor, where the bladder can not provide enough power to micturate regularly, can also be identified with this new nomograph, which again can not be diagnosed with the Abrams-Griffiths nomogram.
 Contents Abstract i Acknowledgement ii Nomenclature iii List of Tables vi List of Figures vi Contents viii Chapter 1 Introduction 1.1 Introduction 1 1.2 Abstract of Lower Urinary System 2 1.3 Methods of clinical examination and diagnosis 4 1.3.1 Urodynamic study 5 1.3.2 Urethral pressure, urine flow rate and urine velocity profiles 8 1.3.3 Diagnostic method and Abrams-Griffiths nomogram 9 1.3.4 Disadvantage of current diagnostic method 10 1.4 Paper survey 10 1.5 Objective 13 Chapter 2 Mathematic Formulations 2.1 Governing Equation 15 2.2 Turbulence Model ( Model) 16 2.3 Transform Governing Equation 17 Chapter 3 Numerical Solution Procedure 3.1 Discretization Equation 20 3.2 Numerical Method 22 Chapter 4 Experimental Method 4.1 Objective and Method 28 4.1.1 Objective 28 4.1.2 Method 28 4.2 Experiment Apparatus 29 4.3 Experiment Procedure 30 4.4 Operating Ranges for Experiment 31 Chapter 5 Result and Discussion 5.1 Grid System 33 5.2 Experiment and CFD Results 33 5.2.1 Grid-Independent test 34 5.2.2 Comparisons of measurements and CFD predictions 34 5.3 Discussion 36 5.3.1 Effect of Obstructed shape 36 5.3.2 Effect of Flow rate and Obstructed degree 36 5.4 Dimensionless Nomogram 38 Chapter 6 Conclusion and Future work 41 Reference 43