Experimental and computational fluid dynamics study of lower urinary tract system

• Main Author: 黃慶祥
• Other Authors: 林昭安
• Format: Others
• Language: en_US
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/00854745825028783123

碩士 === 國立清華大學 === 動力機械工程學系 === 92 === In order to provide reliable measured data to validate the CFD predictions, a lower urinary tract system model is fabricated based on the reconstruction of the CT images of patients with BOO. The measured data will help to identify the underlying cause of this difference between the CFD results and the clinical data. Due to the fabricational complexity of the real 3-D urethral model, the adopted model is a straight axi-symmetrical model, but having the same cross-sectional area of the real urethral. To investigate the effects of this simplification, computational study will also be directed to investigate the influences of the 2-D (axi-symmetric) and 3-D geometry on the pressure distributions. Since the present study is to clarify through experimental measurements the cause of the mismatch between the CFD prediction and the clinical data, with the latter being 10 times larger than the former one. Based on the present measurements, this difference might not be caused by the minor loss due to the change of geometry. Instead, other mechanism, which is not accounted for in the present CFD simulation, could be presented. The likely cause is that an opening pressure should be present to open the elastic regions of the prostate and sphincter. This region is in general closed to prevent the urine from leaking from bladder. For a BOO patient, the opening pressure required is even higher.