Biomedical Fluid Mechanics

Biomedical fluid mechanics examines the behaviour of biological fluids—most notably blood, lymph and interstitial perfusates—within living tissues and medical devices. Central to the discipline are the principles of fluid dynamics as applied to complex geometries, compliant boundaries and non-Newtonian rheology. Blood flow, with its shear-thinning viscosity and cellular components, is guided by pressure gradients, vessel elasticity and pulsatile driving from the heart, and underpins circulation from large arteries down to microvessels. Interstitial and lymphatic flows govern tissue homeostasis, drug delivery and immune surveillance, while engineered constructs such as tissue-engineering scaffolds depend critically on pore-scale flow to supply nutrients and remove waste. Biomedical fluid mechanics integrates theoretical models (Navier–Stokes and porous-media formalisms), high-fidelity computational simulations and in vitro experiments to predict flow patterns, wall shear stress distributions and mass-transport phenomena. Insights into flow-induced forces on cells inform mechanotransduction, vascular remodelling, atherogenesis and device performance. Advances in imaging, microfabrication and machine learning are now enabling patient-specific modelling, real-time flow assessment and optimised design of implants, bioreactors and microfluidic diagnostic platforms.

Research from Nature Portfolio

A novel permeability test bench has been developed for porous scaffolds used in tissue engineering. Compliant with ASTM guidelines, the system employs a closed-loop hydraulic circuit to measure intrinsic permeability across a wide range of scaffold architectures, validating results against an alternative acoustic method. The protocol enables repeatable, standardised characterisation of transport properties in both regularly patterned and random structures, thereby facilitating optimisation of mass transport in clinical-scale constructs.

In parallel, machine-learning-accelerated haemodynamic simulations have been applied to congenital aortic coarctation. By training neural networks on high-throughput, parallelised fluid–structure interaction data, researchers rapidly predicted pressure gradients and wall shear stress for varying stenosis severity and blood properties. The framework achieves clinical-level accuracy with minimal input data, promising non-invasive assessment of disease severity and personalised therapeutic planning.

Research from all publishers

An advanced computational model coupling Navier–Stokes and Darcy–Brinkman equations has elucidated radial-flow packed-bed bioreactor performance. Simulations of oxygen and glucose transport in axisymmetric constructs revealed how radial flux distribution controls pericellular nutrient concentrations and cell viability, providing design criteria for uniform perfusion and real-time control in large-scale bioreactors.

Complementing this, a computational fluid-dynamics study of biomimetic porous scaffolds quantified the impact of tortuosity on permeability and wall shear stress. By comparing gyroid-based and cancellous-bone-inspired architectures, investigators showed that modest adjustments in pore pathway convolution dramatically alter flow resistance and mechanical cues, thereby guiding scaffold design to match native tissue transport characteristics.

In the microvasculature, clinical ektacytometry studies have characterised red blood cell deformability in early-stage diabetes. By measuring cell elongation under controlled shear, researchers established a deformability index that correlates with disease severity and altered osmotic fragility. These findings link rheological changes to impaired oxygen delivery and suggest new prognostic markers for vascular complications.

Biomedical Fluid Mechanics publication trend

The graph below shows the total number of articles in biomedical fluid mechanics across all publications each year (not limited to Nature Index journals).

Technical terms

Non-Newtonian fluid: A fluid whose viscosity varies with shear rate, as in blood where viscosity decreases under faster flow.

Wall shear stress (WSS): Tangential force per unit area exerted by flowing fluid on a bounding surface.

Perfusion bioreactor: A device that circulates physiological fluid through a porous scaffold to deliver nutrients and apply shear to cells.

Permeability: A measure of how easily fluid passes through a porous medium, critical to nutrient transport in scaffolds.

Tortuosity: The degree of path winding in a porous network, influencing flow resistance and solute diffusion.

Porous-media formalism: Mathematical description of flow through media composed of solid matrix and interconnected pores.

Pressure gradient: The spatial change in fluid pressure that drives flow through vessels or devices.

Fluid–structure interaction (FSI): Coupled modelling of fluid flow and deformation of flexible boundaries such as blood-vessel walls.

References

1. Adaptable test bench for ASTM-compliant permeability measurement of porous scaffolds for tissue engineering. Scientific Reports (2024).
2. Accelerating massively parallel hemodynamic models of coarctation of the aorta using neural networks. Scientific Reports (2020).
3. The Effect of Tortuosity on Permeability of Porous Scaffold. Biomedicines (2023).
4. Altered RBC deformability in diabetes: clinical characteristics and RBC pathophysiology. Cardiovascular Diabetology (2024).