Design and Flow Analysis of Impeller in Total Artificial Heart

• Main Authors: Lin, Jih-Yih, 林志益
• Other Authors: Young Der-Liang, Hsieh Shang-Hsien
• Format: Others
• Language: zh-TW
• Published: 1997
• Online Access: http://ndltd.ncl.edu.tw/handle/48844871515203631287

碩士 === 國立臺灣大學 === 土木工程學系 === 85 === Implantation of total artificial heart (T.A.H.) into the human bodyhas inspired courage in clinic, yet the strive to develop a new-typeT.A.H. is still undergoing. The former Phoenix pneumatic-type T.A.H.is often criticized for its low mobility and high possibility ofinfection. The newly developed Phoenix electro-hydraulic T.A.H. ismainly aimed at tackling these shortcomings. The movement of bloodflow inside the artificial heart is driven by a set of impellers inconjunction with DC motors. Due to the limited physiological chestspace for implanting the T.A.H., these driving devices are of verysmall sized and little information is available for their performance. The experiments conducted by the University of Utah did not revealsatisfactory results, and a theoretical analysis was inevitable.The present study utilizes the partial differential equation( PDE )method to generate surface representation of impellers. Other detailedstructures are designed with the popular CAD packages, such as AutoCADand Matlab. Flow Analysis around the impeller is performed by using thecommercial code, CFX4, to solve the fully incompressible three-dimensionalNavier- Stokes equations plus turbulence model with moving grids Numericalresults show that secondary flows are observed in the vicinity of blades.These secondary flows contribute to major energy loss in the pumping device.One way to improve the efficiency is through the optimization design todestroy these flow structures of secondary eddies.