Shear-Stress Occurrence in a Single Use Flowmeter

In this article, Flowmeister BV shares insights and conclusions that were obtained in a guided experiment on the quantitive effect of shear-stress through one of our flowmeters.

Context to this investigation was the intention to start using a new design of our Single Use flowmeter in life-science applications.

The potential of a Single Use flowmeter is very broad, from Biopharmaceutical liquids to measuring bloodflow.

We want to offer potential users additional insight to the contributors of shear-induced defects in the static part of a full flow-path.

Physical setups as used to obtain data:

To transport the test-liquid through the flowpath, we have used a mechanically operated syringe. We compared the cell-viability after flow through three flowpaths:

1. Control 1 = Straight tube
2. Control 2 = Straight tube, interrupted by Triclamp-Triclamp connection
3. DUT = Straight tube, interrupted by Triclamp-flowmeter-triclamp

Original test-reports and detailed description of the used setup are available upon request.

Performed and professionally documented by Regen Biomedical, we were positively surprised to see the following conclusions and findings.

Findings:

• In each test-cycle we measured a slight loss of cell-viability.
• The absolute percentage of cell-viability-loss showed nearly no variance between test setup 1, 2 or 3.
• The absolute percentage of cell-viability-loss correlates with the liquid flowrate (flow-speed)

Conclusions:

The practical test-findings resemble the previously made COMSOL computational simulations.

Although the flowmeter inner geometry has a few unavoidable edges, the physical design directs the inner flow in such a way that no significant cell-damage is caused.

Recommendations:

With the proven relationships between flowpath and flowspeed, we recommend the use of our ultrasonic flowmeter for applications where flow-measurement is of added value in shear-stress-sensitive media.

In order to obtain minimized loss of cell-viability, it is important to keep the flow-speed as low as possible.

Our upgraded Single Use flowmeter is capable of measuring accurately at relative low flow-speed, which is beneficial for low stress and high cell-survival.

Flowmeister delivers non-metal flowpath solutions from 10 nanoliter up to 900 liter per minute.

Supported by our European partners, we’re glad to provide you with the solutions to fill in your flow-measurement or flow-control applications, both in Single Use as in regular applications.