# Computational Fluid Dynamic Analysis of Fluid Motion and Volumetric Gas–Liquid Mass Transfer in Agitated Platelet Concentrate Storage

## TL;DR

This paper uses computer simulations to study how agitation affects platelet storage, finding that it increases stress and fluid motion but oxygen supply depends more on container material than agitation.

## Contribution

The study introduces a CFD-based approach to analyze mechanical stress and oxygen transfer in platelet storage under agitation.

## Key findings

- Agitation increases fluid velocity and wall shear stress while maintaining sinusoidal motion symmetry.
- Oxygen transfer is enhanced in open containers but constrained by storage material permeability.
- Reducing agitation may minimize platelet damage without compromising oxygenation.

## Abstract

Computational fluid dynamics (CFD) offers a powerful tool in characterizing the complex biophysical environment inducing by dynamic storage conditions, providing insights often beyond the reach of conventional experimental approaches. As our understanding of platelet (PLT) biology has advanced, increased attention has been directed toward mechanical stresses, attributing shear forces encountered during collection, processing, and storage to an acceleration decline in PLT concentrate (PC) quality. CFD simulations using the volume of fluid model were used to simulate PC storage under varying agitation frequencies. Key parameters assessed include fluid velocity, wall shear stress (WSS), and gas–liquid mass transfer. Agitation increased fluid velocity and WSS while preserving the temporal symmetry characteristic of sinusoidal motion. Enhanced oxygen transfer was observed in open‐top containers; however, when accounting for the gas permeability of storage materials, oxygen availability was ultimately constrained by container permeability rather than fluid motion. These results highlight the dual role of agitation: promoting oxygen transfer while simultaneously introducing mechanical stress that may contribute to PLT storage lesions. Importantly, since oxygen supply is limited by container permeability, reducing agitation could minimize shear‐induced PLT damage without compromising oxygenation. Future optimization strategies may involve modifying storage container geometry or permeability to further improve oxygen delivery during storage.

Platelets (PLTs) are small blood cells that play a vital role in stopping bleeding. After donation, they are stored in special bags, but their quality decreases over time. One reason for this decline is the mechanical stress they experience during collection, processing, and storage. PLT bags are often agitated (gently shaken) to help maintain oxygen supply, but this movement has also been suggested to increase stress on the cells. Using computer simulations, we studied how agitation affects fluid flow, mechanical stress, and oxygen transfer in stored PLTs. We found that agitation increases fluid movement and stress on PLTs. It also improves oxygen transfer when PLTs are stored in open containers. However, in standard storage bags, oxygen availability is mostly determined by the material of the bag, not by agitation. These results suggest that reducing agitation could help to protect PLTs from stress without reducing oxygen supply. Future improvements in PLT storage may come from designing bags with better materials or shapes to optimize oxygen transfer, rather than relying heavily on agitation.