Development of low-cost rotational rheometer

Area of Science:

• Engineering
• Fluid Dynamics
• Materials Science

Background:

• Non-Newtonian fluids, such as active sludge in membrane bioreactors, exhibit shear-thinning properties crucial for system optimization.
• Accurate rheological characterization is essential for understanding and controlling systems involving these complex fluids.
• Traditional rheometers are often prohibitively expensive, limiting accessibility for research and development.

Purpose of the Study:

• To design and construct a low-cost rotating rheometer.
• To accurately determine the rheology, specifically shear-dependent viscosity, of Newtonian and non-Newtonian liquids.
• To provide an accessible tool for optimizing engineering systems that utilize non-Newtonian fluids.

Main Methods:

• A low-cost rotating rheometer was built based on established rheometer principles.
• Calibration was performed using Newtonian liquids against a Brookfield viscometer.
• Validation involved testing non-Newtonian xanthan gum solutions and comparing results with a Brookfield viscometer and external data.

Main Results:

• The developed rheometer successfully determined the rheology of both Newtonian and non-Newtonian liquids.
• Calibration and validation confirmed the accuracy of the low-cost instrument.
• The study discusses the impact of shear rates and provides guidance for practical application.

Conclusions:

• A cost-effective rheometer can accurately measure the shear-dependent viscosity of non-Newtonian fluids.
• This innovation makes advanced rheological analysis more accessible for various engineering applications.
• The findings support the optimization of systems involving shear-thinning fluids like active sludge.