FSI modeling and simulation of blood viscosity impacts on cavitation in mechanical heart valves

Heart valve replacements are critical for patients with valve malfunctions, and the tri-leaflet mechanical heart valve (tMHV) is one of the most durable options available. The tMHV is used to replace malfunctioning heart valves, restoring normal blood flow with exceptional durability, often lasting...

Full description

Saved in:
Bibliographic Details
Main Authors: Joseph Amponsah, Archibong Archibong-Eso, Aliyu M. Aliyu, Tabbi Wilberforce Awotwe
Format: Article
Language:English
Published: Elsevier 2024-11-01
Series:International Journal of Thermofluids
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S2666202724004026
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850244704336084992
author Joseph Amponsah
Archibong Archibong-Eso
Aliyu M. Aliyu
Tabbi Wilberforce Awotwe
author_facet Joseph Amponsah
Archibong Archibong-Eso
Aliyu M. Aliyu
Tabbi Wilberforce Awotwe
author_sort Joseph Amponsah
collection DOAJ
description Heart valve replacements are critical for patients with valve malfunctions, and the tri-leaflet mechanical heart valve (tMHV) is one of the most durable options available. The tMHV is used to replace malfunctioning heart valves, restoring normal blood flow with exceptional durability, often lasting up to 20 years without needing replacement. This durability makes tMHVs particularly suitable for patients under 60. However, mechanical issues like cavitation can undermine the valve's functionality, posing risks to both its longevity and the overall efficacy of cardiovascular treatments. While previous studies have investigated some aspects of cavitation in these valves, the combined effects of blood viscosity and fluid-structure interaction (FSI) on cavitation dynamics remain insufficiently explored.This work models and numerically simulate the influence of blood viscosity on cavitation within tMHVs, using FSI principles. A detailed geometric model of the tMHV was developed, incorporating experimental data and non-Newtonian fluid behaviour to accurately replicate blood flow. Simulations were conducted in ANSYS Fluent R1® using a transient solver to capture the dynamic FSI, with the Carreau-Yasuda model representing blood's shear-dependent viscosity. Cavitation was observed at pressures as low as 4.5 Pa—well below the 15-20 Pa range typically reported—indicating a higher vulnerability than previously recognized. The simulations further showed significant vapour bubble formation, with the maximum vapour volume fraction reaching 0.953. High-speed leakage flows, peaking at 11 m/s during valve closure, were also noted, considerably exceeding velocities observed in earlier studies.These findings demonstrate that cavitation occurs when blood pressure drops below vapour pressure, causing vapour bubbles to form. These bubbles generate shock waves that can damage the valve surfaces and surrounding tissue. Insights from this study will aid in the design of next-generation tMHVs with optimised flow dynamics, potentially reducing cavitation risks and enhancing patient outcomes by minimising valve-associated complications.
format Article
id doaj-art-dc413375177b4cf5bf4ebf0011e961f5
institution OA Journals
issn 2666-2027
language English
publishDate 2024-11-01
publisher Elsevier
record_format Article
series International Journal of Thermofluids
spelling doaj-art-dc413375177b4cf5bf4ebf0011e961f52025-08-20T01:59:39ZengElsevierInternational Journal of Thermofluids2666-20272024-11-012410096210.1016/j.ijft.2024.100962FSI modeling and simulation of blood viscosity impacts on cavitation in mechanical heart valvesJoseph Amponsah0Archibong Archibong-Eso1Aliyu M. Aliyu2Tabbi Wilberforce Awotwe3Iowa State University, Department of Mechanical Engineering, 1801 S Lincoln Way, Ames, IA, 50011, USAUniversity of Birmingham, Department of Mechanical Engineering, Dubai Campus, Dubai P.O. Box 341799, United Arab Emirates; Corresponding author.University of Lincoln, Brayford Pool, School of Engineering and Physical Sciences, LN6 7TS, UKFaculty of Natural, Mathematical and Engineering Sciences, Kings College London, Strand, London, WC2R 2LS, UKHeart valve replacements are critical for patients with valve malfunctions, and the tri-leaflet mechanical heart valve (tMHV) is one of the most durable options available. The tMHV is used to replace malfunctioning heart valves, restoring normal blood flow with exceptional durability, often lasting up to 20 years without needing replacement. This durability makes tMHVs particularly suitable for patients under 60. However, mechanical issues like cavitation can undermine the valve's functionality, posing risks to both its longevity and the overall efficacy of cardiovascular treatments. While previous studies have investigated some aspects of cavitation in these valves, the combined effects of blood viscosity and fluid-structure interaction (FSI) on cavitation dynamics remain insufficiently explored.This work models and numerically simulate the influence of blood viscosity on cavitation within tMHVs, using FSI principles. A detailed geometric model of the tMHV was developed, incorporating experimental data and non-Newtonian fluid behaviour to accurately replicate blood flow. Simulations were conducted in ANSYS Fluent R1® using a transient solver to capture the dynamic FSI, with the Carreau-Yasuda model representing blood's shear-dependent viscosity. Cavitation was observed at pressures as low as 4.5 Pa—well below the 15-20 Pa range typically reported—indicating a higher vulnerability than previously recognized. The simulations further showed significant vapour bubble formation, with the maximum vapour volume fraction reaching 0.953. High-speed leakage flows, peaking at 11 m/s during valve closure, were also noted, considerably exceeding velocities observed in earlier studies.These findings demonstrate that cavitation occurs when blood pressure drops below vapour pressure, causing vapour bubbles to form. These bubbles generate shock waves that can damage the valve surfaces and surrounding tissue. Insights from this study will aid in the design of next-generation tMHVs with optimised flow dynamics, potentially reducing cavitation risks and enhancing patient outcomes by minimising valve-associated complications.http://www.sciencedirect.com/science/article/pii/S2666202724004026Fluid-structure interactionBlood viscosityCavitationTri-leaflet mechanical heart valveVapor bubbles
spellingShingle Joseph Amponsah
Archibong Archibong-Eso
Aliyu M. Aliyu
Tabbi Wilberforce Awotwe
FSI modeling and simulation of blood viscosity impacts on cavitation in mechanical heart valves
International Journal of Thermofluids
Fluid-structure interaction
Blood viscosity
Cavitation
Tri-leaflet mechanical heart valve
Vapor bubbles
title FSI modeling and simulation of blood viscosity impacts on cavitation in mechanical heart valves
title_full FSI modeling and simulation of blood viscosity impacts on cavitation in mechanical heart valves
title_fullStr FSI modeling and simulation of blood viscosity impacts on cavitation in mechanical heart valves
title_full_unstemmed FSI modeling and simulation of blood viscosity impacts on cavitation in mechanical heart valves
title_short FSI modeling and simulation of blood viscosity impacts on cavitation in mechanical heart valves
title_sort fsi modeling and simulation of blood viscosity impacts on cavitation in mechanical heart valves
topic Fluid-structure interaction
Blood viscosity
Cavitation
Tri-leaflet mechanical heart valve
Vapor bubbles
url http://www.sciencedirect.com/science/article/pii/S2666202724004026
work_keys_str_mv AT josephamponsah fsimodelingandsimulationofbloodviscosityimpactsoncavitationinmechanicalheartvalves
AT archibongarchibongeso fsimodelingandsimulationofbloodviscosityimpactsoncavitationinmechanicalheartvalves
AT aliyumaliyu fsimodelingandsimulationofbloodviscosityimpactsoncavitationinmechanicalheartvalves
AT tabbiwilberforceawotwe fsimodelingandsimulationofbloodviscosityimpactsoncavitationinmechanicalheartvalves