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Mavroudis, Angelos

University of British Columbia

Severe gastrointestinal hemorrhaging presents a complex challenge that can lead to potentially fatal outcomes. Although existing medical solutions offer some assistance in managing internal bleeding, they are unreliable due to their limitations. Recent work on innovative hemostatic powders has shown promising results in effectively controlling bleeding without imposing any risk to the patient. However, to efficiently deliver this hemostatic agent, an optimized delivery system is required. The hemostatic powder is characterized by adhesive properties that negatively impact its flowability. This research aims to create a prototype of a medical device to test and improve the flow of an adhesive hemostatic powder through a 0.002 m in diameter and 1.47 m in length catheter. A detailed experimental analysis is performed to understand which parameters and how they affect the performance of the delivery system. In the experiments, the performance of the delivery system is characterized based on the delivery time and the powder mass deposition at the outlet of the catheter. A high-velocity gas flow is responsible for transporting the powder through a catheter and into a sealed container. A pressure regulator regulates the maximum pressure of the system at 68 kPa (10 psi), while the flow rate is adjusted using a gas flow regulator. Three different flow rates are examined in the experimental part of this work: 0.37 m³/h, 0.31 m³/h, and 0.23 m³/h. Furthermore, to improve the device, different designs are being tested. The effects of dimensional changes on powder flowability are being examined with respect to the efficiency of powder delivery through the catheter. A primary modeling approach for turbulent and dense gas-solid multiphase flows is being presented using computer-aided engineering. Computational fluid dynamics (CFD) and discrete element methods (DEM) are combined to develop a computational model of the granular flow. This model is defined by specific attributes of the powder and the carrying fluid. The numerical results verification is supported by experimental data.

Text

2023-10-18

Attribution-NonCommercial-NoDerivatives 4.0 International

http://hdl.handle.net/2429/86195

Mechanical Engineering

University of British Columbia

UBCV

http://creativecommons.org/licenses/by-nc-nd/4.0/