Year: 2025
Type: article
Abstract: This study explores recent advancements in viscometry techniques for precise viscosity measurements, focusing on automating the widely used Ubbelohde capillary viscometer. Previous attempts at automation utilising single-camera and infrared laser techniques demonstrated initial promise; however, these approaches exhibited significant limitations. This research introduces the design and validation of a new automated kinematic capillary viscometer system utilising real-time computer vision for simultaneous meniscus detection and timing up to three viscometers. The system incorporates two waterproof cameras per Ubbelohde viscometer connected to a computer running custom-made ViscoCheck software, with temperature control managed by an Arduino microcontroller. It maintains the water bath temperature within ± 0.5 °C and measures flow time with ± 0.01 s resolution. The system was validated by measuring the viscosity of a binary ethanol–hexane mixture across the entire mole fraction range at a constant pressure of 101.325 kPa and a temperature of 298.15 K. Results were compared with literature values and correlated using the Grunberg–Nissan (G–N) and McAllister three-body models. Excess molar volumes ( V E ) and viscosity deviations ( Δƞ ) were calculated to assess accuracy in capturing complex liquid mixture behaviour. Findings revealed general agreement between experimental and reference data. The G–N model showed excellent agreement, exhibiting a low standard deviation (0.036) and absolute average deviation (1.648%). These results demonstrate the system's potential as a reliable tool for precise automated viscosity measurements across various industrial applications.
Language: English
Subfield: Fluid Flow and Transfer Processes
Field: Chemical Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,490
OpenAlex ID: W4410922301