Slip and turbulence phenomena in journal bearings with application to implantable rotary blood pumps

Abstract This paper describes an investigation into journal bearings with geometries and working fluid similar to centrifugal blood pumps. The aim is to describe the phenomena that cause these journal bearings to deviate from classical predictions. Experimental, analytical and numerical methods are used to investigate the behaviour of a range of bearings with geometries and working fluid similar to blood pumps. It was found that the clearance had a significant effect on the force-eccentricity characteristic of the bearing, with smallest and largest clearances deviating from classical predictions. Experimentally measured pressure distributions show that slip occurs when the clearance is small and that turbulence occurs with the largest clearances. The effects of these phenomena on lubricant pressure and blood compatibility are discussed.

[1]  F. W. Ocvirk.  Short-bearing approximation for full journal bearings , 1952 .

[2]  A. Cheung,et al.  Off-pump implantation of the HeartWare HVAD left ventricular assist device through minimally invasive incisions. , 2011, The Annals of thoracic surgery.

[3]  R. Ponalagusamy,et al.  Blood Flow Through an Artery with Mild Stenosis: A Two-layered Model, Different Shapes of Stenoses and Slip Velocity at the Wall , 2007 .

[4]  J. B. Segur,et al.  Viscosity of Glycerol and Its Aqueous Solutions , 1951 .

[5]  F. Pagani.  Continuous-flow rotary left ventricular assist devices with "3rd generation" design. , 2008, Seminars in thoracic and cardiovascular surgery.

[6]  D B Olsen,et al.  The history of continuous-flow blood pumps. , 2000, Artificial organs.

[7]  J A Reizes,et al.  VentrAssist hydrodynamically suspended, open, centrifugal blood pump. , 2000, Artificial organs.

[8]  W A Smith,et al.  Stable blood lubricated hydrodynamic journal bearing with magnetic loading. , 1998, ASAIO journal.

[9]  Hyun-Duck Kwak,et al.  Numerical prediction of slip flow effect on gas-lubricated journal bearings for MEMS/MST-based micro-rotating machinery , 2005 .

[10]  Y. Nubar.  Blood flow, slip, and viscometry. , 1971, Biophysical journal.

[11]  Harish Hirani,et al.  Rapid performance evaluation of journal bearings , 1997 .

[12]  Chengwei Wu,et al.  Abnormal behavior of a hydrodynamic lubrication journal bearing caused by wall slip , 2005 .

[13]  Mitsuo Umezu,et al.  EVAHEART: an implantable centrifugal blood pump for long-term circulatory support. , 2002, The Japanese journal of thoracic and cardiovascular surgery : official publication of the Japanese Association for Thoracic Surgery = Nihon Kyobu Geka Gakkai zasshi.

[14]  Katharine H Fraser,et al.  The use of computational fluid dynamics in the development of ventricular assist devices. , 2011, Medical engineering & physics.

[15]  Ulrich Steinseifer,et al.  Experimental and analytical performance evaluation of short circular hydrodynamic journal bearings used in rotary blood pumps. , 2013, Artificial organs.

[16]  Akbar Rahideh,et al.  Optimization of Centrifugal Pump Characteristic Dimensions for Mechanical Circulatory Support Devices , 2016, ASAIO journal.

[17]  V. Thourani,et al.  Third-Generation Continuous Flow Left Ventricular Assist Devices , 2010, Innovations.

[18]  D. Farrar,et al.  A versatile intracorporeal ventricular assist device based on the thoratec VAD system. , 2001, The Annals of thoracic surgery.

[19]  Sang Myung Chun,et al.  Study on mixing flow effects in a high-speed journal bearing , 2001 .

[20]  Akbar Rahideh,et al.  The Effects of Ambulatory Accelerations on the Stability of a Magnetically Suspended Impeller for an Implantable Blood Pump. , 2016, Artificial organs.

[21]  K. Litwak,et al.  HeartMate III: Pump Design for a Centrifugal LVAD with a Magnetically Levitated Rotor , 2001, ASAIO journal.