Orbiting sphere viscometer operated in resonant orbiting mode

We present the operation of a previously introduced orbiting sphere viscometer in resonant mode at small amplitudes to demonstrate the feasibility of miniaturization. In chemical processes control, often comparability of novel viscosity measurement and sensing principles with well-established principles is essential since the measured viscosity crucially depends on the measurement parameters utilized (e.g., shear rate, oscillation frequency, etc.). The orbiting sphere viscometer on one hand mimics the falling ball principle and on the other hand extends its properties. It can be operated in an orbiting mode which, for large radii, reproduces the interaction of a linearly moving sphere with the surrounding liquid. For smaller amplitudes, the interaction is more comparable to other oscillating viscometer principles. In the present paper, we focus on this latter mode of operation, show its feasibility and present according sample results.