Flow uniformity in oxygenators with different outlet port design

Area of Science:

• Biomedical Engineering
• Fluid Dynamics
• Medical Device Design

Background:

• Extracapillary membrane oxygenators are crucial for cardiopulmonary support.
• Optimizing blood flow distribution is essential for efficient oxygenation and patient safety.
• Current designs with tangential outlets may lead to non-uniform flow patterns.

Purpose of the Study:

• To evaluate the optimum design of a blood outlet port structure for uniform blood flow in an extracapillary membrane oxygenator.
• To compare the flow characteristics of a tangential outlet port design with a newly engineered vertical outlet port design.

Main Methods:

• Utilized a cylindrical extracapillary membrane oxygenator (HPO-20) with both tangential and vertical blood outlet port configurations.
• Employed 120 insulated copper-wire electrodes to visualize blood-side flow.
• Measured dimensionless fluid arrival time at each electrode to assess flow uniformity.

Main Results:

• The tangential HPO-20 exhibited non-uniform blood flow, particularly in the outer blood channel.
• The vertical HPO-20 demonstrated significantly more uniform blood flow distribution.
• Reduced stagnation and channeling were observed in the vertical outlet port design.

Conclusions:

• A vertical blood outlet port design leads to more uniform blood flow distribution in extracapillary membrane oxygenators compared to a tangential design.
• This improved flow uniformity can enhance oxygenator performance and potentially patient outcomes.
• The findings suggest a design modification for optimizing extracapillary membrane oxygenator efficiency.