Session: Research Posters

Paper Number: 113349

113349 - Cfd Analysis of the Impacting Factors of Patients Varying Blood Conditions on the Artificial Heart’s Device Performance 

Centrifugal pumps have been widely used in the industry and can be applied as blood pump for the cardiovascular circulation. It plays a critical role in maintaining a patient’s circulatory transportation by providing the needed kinetic energy to drive blood. Since the working principle of such an axisymmetric turbomachinery is to transfer energy between impeller blades and the impacting blood, the impeller is more easily affected by fluid-structure interaction due to the fast rotation and large contacting area. Therefore, the working performance of the blood pump is inclined to be affected by varying fluid behavior and may lead to a deviation from the designed optimal operating zone. Compare to most research investigating the blade imposed influence on blood or red blood cells, this study investigates the influence of blood behavior on the device performance. The computational fluid dynamics (CFD) technology is carried out to reveal shear stress, turbulent kinetic loss and other flow field details which are hard to obtain through experiments. Both the k-e and SST models are selected as the Reynolds-averaged Navier-Stokes (RANS) models for the computationally efficient calculation of turbulent flow. Other external characteristics of the artificial heart in terms of the pump head, pressure loss, shaft work, and device efficiency are also investigated. Moreover, considering some typical situations that some patients may experience, such as high blood pressure, hyperlipidemia, abnormal temperature, and etc., the artificial pump’s performance and operation safety are comprehensively evaluated by means of numerical simulation as well. The most influential factor is then analyzed through the correlation methods. Meanwhile, the numerical model is further validated by comparing it with the laboratory's benchmark test data provided by U.S. Food and Drug Administration (FDA). The velocity distribution and pump head from the simulation results show good agreement with the experimental data. Results of this study show that the artificial heart condition responds to the varying blood condition, and all abnormal blood condition, especially hyperlipidemia causes device energy burden and shifts its best efficiency point (BEP) more obviously. In some extreme conditions, the blood pressure can be hardly sustained by the artificial heart as the energy loss becomes severe and thus need rotation adjustment to sustain the required pressure or device power. Among varying blood conditions of pressure, density, viscosity, and temperature, the pearson and spearman grade correlation coefficients can be used to qualitatively reveal their influence on different performances termed as torque, output pressure, and energy efficiency. This study helps understand the effects of blood conditions on artificial heart device, and gives corresponding guidelines for its further design and safety control strategy for similar medical devices.

Keywords: Artificial heart, blood pump, hyperlipidemia, performance analysis, device safety.

Presenting Author: Zheng Cao School of Chemical Engineering and Technology,Xi’an Jiaotong University

Presenting Author Biography: Zheng CAO is an Associate Professor, Ph.D. in the Department of Process Equipment & Control Engineering, Xi’an Jiaotong University. His major interest involves energy recovery; fluid machinery; hydraulic engineering; artificial heart; computational fluid dynamics; and willing to learn&try anything new;

Authors:

Zheng Cao School of Chemical Engineering and Technology,Xi’an Jiaotong University
Qi Xia Xi'an Jiaotong University
Jianqiang Deng Xi’an Jiaotong University
Lin Lu The Hong Kong Polytechnic University