Design and simulation of mechanical ventilators

Area of Science:

• Biomedical Engineering
• Mechanical Engineering
• Computational Fluid Dynamics

Background:

• The COVID-19 pandemic highlighted critical shortages of medical equipment, particularly ventilators.
• Low-cost mechanical ventilators offer a potential solution to address equipment deficits in healthcare settings.

Purpose of the Study:

• To numerically predict the performance of two novel low-cost mechanical ventilator designs.
• To compare the efficacy of an Ambu-bag-based design versus a piston-cylinder design.
• To identify methods for achieving pressure control mode (PCM) and volume control mode (VCM).

Main Methods:

• Numerical analysis using ANSYS Workbench platform.
• Fluid-structure interaction (FSI) analysis for the first design.
• Computational fluid dynamics (CFD) with a moving boundary for the second design.

Main Results:

• The Ambu-bag-based ventilator demonstrated challenges in controlling ventilation variables, risking patient harm like barotrauma.
• The piston-cylinder mechanical ventilator provided more satisfactory delivered parameters for patients.
• Key factors influencing ventilator output include inlet flow, cylinder length, and piston diameter.

Conclusions:

• The piston-cylinder mechanical ventilator design is a more promising alternative for low-cost ventilation.
• Optimizing design parameters like inlet flow, cylinder length, and piston diameter is crucial for effective mechanical ventilation.
• Numerical simulations are valuable tools for evaluating and refining medical device designs.