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Updated: Jul 22, 2026
08:02
Thin Film Composite Silicon Elastomers for Cell Culture and Skin Applications: Manufacturing and Characterization
Published on: July 3, 2018
Summary
Human perception of liquid viscosity follows a power law, correlating apparent viscosity with absolute viscosity across a wide range. This finding applies to various sensory judgment methods.
Area of Science:
- Rheology
- Psychophysics
- Materials Science
Background:
- Understanding the relationship between objective material properties and subjective human perception is crucial.
- Viscosity, a measure of a fluid's resistance to flow, is a key material property with significant perceptual implications.
Purpose of the Study:
- To quantify the relationship between the absolute viscosity of silicone liquids and their perceived apparent viscosity.
- To investigate how different sensory methods influence viscosity perception.
Main Methods:
- Participants numerically judged the apparent viscosity of silicone liquids (10.3–95,000 cP) using three methods: bottle shaking/turning, blindfolded stirring, and open-eyed stirring.
- Statistical analysis was performed to determine the relationship between absolute and apparent viscosity.
Main Results:
- Apparent viscosity increased as a fractional power of absolute viscosity for all judgment methods.
- The determined exponents ranged from 0.42 to 0.46.
- Perceived viscosity demonstrated adherence to the psychophysical power law.
Conclusions:
- Human perception of viscosity is quantitatively predictable and follows a power-law relationship with the fluid's absolute viscosity.
- The psychophysical power law effectively models the perception of viscosity across different sensory assessment techniques.
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