Simulation on 3D Flow Characteristics inside Bronchia of NonHeart Beating Donor Lung
1 Institute of Biothermal Science and Technology, University of Shanghai for Science and Technology, Shanghai 200093, China
2 Institute of Refrigeration and Cryogenic Engineering, University of Shanghai for Science and Technology, Shanghai 200093,China
3 Shanghai Pulmonary Hospital, Shanghai 200433,China
Abstract：Nonheart beating donor (NHBD) lung is expected to be the most potential donor source for clinical lung transplantation, and the low temperature ventilation is normally thought to effectively protect the donor lung in vivo. A 3D asymmetric bronchial model with four levels was formed in this work; computational fluid dynamics (CFD) technique was adopted for investigating the 3D flow characteristics inside NHBD lung bronchia. Results show that there were some differences of dimensionless velocity distribution between inhaling and exhaling, the velocity distribution was also different on the left lung bronchus and the right lung bronchus sections. In particular, the dimensionless velocity of left lobar bronchus was 17 but the right upper lobar was 08. The flow ratios of left and right bronchia were 55% and 45%, respectively. The flow ratio of left inferior lobar bronchus was the largest one, about 35%. This is related to bifurcation angles and diameters changing with varied levels. The average pressure drop coefficients inside bronchia were also obtained here, which was the function of Re as 〖AKC-〗p〗∝Re－06. Because of the existence of asymmetric structure of bronchial and bifurcation space rotation angle, the gas flow in the bronchus became complicated, which is valuable for clinical and experimental study on NHBD lung in situ through cryopreservation.
〖KH2D〗
〖WTHZ〗Key words：〖WTBZ〗〖BP(〗┣┣（英）关键词┫┫〖BP)〗〖HT〗〖ST〗〖WT〗〖HJ〗〖HK〗
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