The application of axial pumps as ventricular assist devices (VADs) requires significant modifications to the size and characteristics of industrial pumps due to the difference in flow fields of industrial and medical pumps. Industrial pumps operate in the region of Reynolds number Re = 108, whereas axial blood pumps operate in Re < 106. The common pump design technique is to rely on the performance of previously designed pumps using the concept of fluid dynamic similarity. Such data are available for industrial pumps as specific speed-specific diameter (n s–d s) graphs. The difference between the flow fields of industrial and medical pumps makes the industrial n s–d s graphs unsuitable for medical pumps and consequently several clinically available axial blood pumps operate with low efficiencies. In this article, numerical and experimental techniques were used to design 62 axial pump impellers with different design characteristics suitable for VADs and mechanical circulatory support devices (MCSDs). The impellers were manufactured and experimentally tested in various operating conditions of flow, pressure, and rotational speed. The hemocompatibility of the impellers was numerically investigated by modeling shear stress and hemolysis. The highest efficiency of each pump impeller was plotted on an n s–d s diagram. The nondimensional results presented in this article enable preliminary design of efficient and hemocompatible axial flow pumps for VADs and MCSDs.
From the *Parks College of Engineering, Aviation and Technology, Saint Louis University, St. Louis, Missouri
†School of Engineering and Materials Science, Queen Mary University of London, London E1 4NS, United Kingdom
‡Department of Cardiology, Barts and the London NHS Trust, London Chest Hospital, London E2 9JX, United Kingdom.
Submitted for consideration March 2017; accepted for publication in revised form September 2017.
Disclosure: The authors have no conflicts of interest to report.
This independent research is funded by the National Institute for Health Research [i4i, Turbocardia, II-LB-1111-20007]. Principal Investigator for the grant is Prof. T. Korakianitis. The views expressed in this publication are those of the authors and not necessarily those of the NHS, the National Institute for Health Research or the Department of Health. The PhD study of S. Mozafari is funded by a QMUL studentship.
Correspondence: Theodosios Korakianitis, ScD, Parks College of Engineering, Aviation and Technology, Saint Louis University, St. Louis, MO 63103. Email: firstname.lastname@example.org.