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arXiv · 2510.18107

In vivo evidence of blood flow slippage: failure of the no-slip boundary condition assumption

Alena Jarolímová·Jaroslav Hron·Karel Tůma·Josef Málek·Radomír Chabiniok·Keshava Rajagopal
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Abstract

The assumption that blood adheres to vessel walls, the ``no-slip'' boundary condition, is an essential premise of cardiovascular fluid dynamics. Yet, whether it holds true \emph{in vivo} has not been established. Using 4D flow magnetic resonance imaging of the human thoracic aorta and modeling blood as a Navier--Stokes fluid, we quantify the velocity of blood at the wall. We find tangential wall velocities of about 30--80\% of the mean luminal velocity, providing clear evidence of blood slippage. To our knowledge, this is the first demonstration that the no-slip condition does not apply to blood flow \emph{in vivo}. This finding challenges a fundamental assumption in cardiovascular modeling and directly affects key blood flow characteristics such as pressure drop, vorticity, wall shear stress, and energy dissipation, all of which play important roles across a wide range of cardiovascular conditions.

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Alena Jarolímová, Jaroslav Hron, Karel Tůma, Josef Málek, Radomír Chabiniok, Keshava Rajagopal. 2025-10-20. In vivo evidence of blood flow slippage: failure of the no-slip boundary condition assumption. https://arxiv.org/abs/2510.18107

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