Parametric study of a bubble removing device for hemodialysis

Area of Science:

• Biomedical Engineering
• Fluid Dynamics
• Medical Device Design

Background:

• Hemodialysis requires effective bubble removal to ensure patient safety.
• Existing methods may have limitations in bubble management.
• This study focuses on designing a novel device for bubble collection during hemodialysis.

Purpose of the Study:

• To design and evaluate a device for removing and collecting bubbles during hemodialysis.
• To analyze the influence of design parameters (inlet diameter, velocity, pitch) on bubble behavior.
• To identify the optimal model for efficient bubble removal in hemodialysis circuits.

Main Methods:

• Computational fluid dynamics (CFD) analysis was employed to simulate bubble movement.
• Key parameters such as swirl number, Taylor number, and lift coefficient were implemented.
• Multiple models (Model 1, Model 2, Model 3) with varying initial diameters and pitches were evaluated.

Main Results:

• Model 1 demonstrated a greater average maximum equilibrium position for bubbles (1.995 mm) compared to Model 2 (1.833 mm).
• Validation with 16,000 bubbles showed 81.53% passed through a specific radial region in Model 1.
• An optimal collection plane was identified at 100 mm from the inlet; Model 3 showed a maximum equilibrium position of 2.24 mm.

Conclusions:

• Model 1 emerged as the most effective design for guiding bubbles to the edge without generating additional ones.
• The parametric study provides a viable prototype for bubble removal in hemodialysis.
• The investigated parameters (Taylor number, Lift coefficient, Swirl number) are significant for bubble movement analysis.