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Uncertainty calculation methodologies in microflow measurements: Comparison of GUM, GUM-S1 and Bayesian approach
J A Sousa1, E Batista1, S Demeyer2
1IPQ - Portuguese Institute for Quality, 2829-513 Caparica, Portugal.
Measurement : Journal of the International Measurement Confederation
|December 21, 2022
Summary
Accurate microflow measurement is critical in medicine and research. This study addresses challenges in precise fluid delivery at micro-to-femto flow rates, discussing error sources and alternative methods for reliable quantification.
Area of Science:
- Medical applications, drug development, Organ-on-a-Chip, bioanalysis, and pandemic response.
Background:
- Accurate fluid delivery is critical in medical applications, impacting patient outcomes.
- Microflow applications (micro-to-femto L/s) are increasingly important but challenging to measure accurately.
- Existing methods face challenges with measurement quality, including mass measurement, evaporation, adsorption, and repeatability.
Purpose of the Study:
- To highlight the critical importance of measurement quality in medical and scientific microflow applications.
- To identify and discuss key sources of error in microflow rate measurements.
- To explore alternative methods for overcoming measurement challenges and evaluating uncertainty.
Main Methods:
- Analysis of established error sources in microflow measurements.
- Discussion of challenges in evaluating measurement uncertainty for low flow rates.
- Review of alternative methodologies developed for microflow applications.
Main Results:
- Identified critical error sources: mass measurement, fluid evaporation, tube adsorption, and pump-related repeatability issues.
- Highlighted difficulties in assessing measurement uncertainty for flow rates near zero.
- Indicated the development and suitability of alternative methods to address these challenges.
Conclusions:
- Ensuring measurement quality is paramount in microflow applications for medical and scientific fields.
- Addressing identified error sources and measurement uncertainty is crucial for reliable microflow quantification.
- Alternative methods offer promising solutions for accurate and reliable microflow measurements.
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