Fluid simulation analysis of ECMO hollow-fiber membrane fabrics from knitting technology

Abstract

The study proposes a fluid simulation and analysis of oxygenated membrane fabrics for Extracorporeal Membrane Oxygenation (ECMO) by applying knitting technology from the field of textile technology. This is aimed at addressing the lack of research on the impact of the oxygenator flow field before and after knitting of oxygenated membrane fabrics. For this investigation, a commercial oxygenator was selected, featuring a polymethylpentene (PMP) hollow fiber membrane as the oxygenator membrane material, along with a knitted yarn made of a 50D/24F polyester low-elasticity filament. The knitting organization utilized warp knitting technology with a pillar stitch/weft lining structure. Through the integration of theoretical geometric modeling and finite element analysis method of flow-solid coupling, the study examined the influence of knitting on the oxygenator before and after the knitting of the PMP membrane material. Extracorporeal membrane oxygenation (ECMO) technology represents a sophisticated equipment within the domain of in vitro medical treatment. The research findings indicated that the total pressure drop in the oxygenator’s flow field was 472.6 Pa for the unknitted PMP membrane and 269.4 Pa for the knitted oxygenator fabric, signifying a near 40% reduction in pressure with the knitted PMP membrane. This reduction in pressure also led to a 50% decrease in turbulence within the flow field. The maximum displacement of the knitted PMP membrane within the flow field was measured at 0.16 mm, whereas the unknitted membrane displayed a maximum displacement of 0.37 mm. The knitted PMP membrane significantly enhanced the pressure and velocity uniformity of the oxygenator’s flow field, resulting in decreased stress-strain effects and improved service life of the oxygenator. In conclusion, the study illustrates that knitting the PMP membrane can substantially improve the flow field distribution of ECMO oxygenators, leading to enhanced oxygenation efficiency and membrane durability.