English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We investigate experimentally the dissolution of an almost sphericalbutyramide particle during its sedimentation, in the low Reynolds high P\'ecletregime. The particle sediments in a quiescent aqueous solution, and its shapeand position are measured simultaneously by a camera attached to a translationstage. The particle is tracked in real time, and the translation stage movesaccordingly to keep the particle in the field of the camera. The measurementsfrom the particle image show that the radius shrinking rate is constant withtime, and independent of the initial radius of the particle. We explain thiswith a simple model, based on the sedimentation law in the Stokes' regime andthe mass transfer rate at low Reynolds and high P\'eclet numbers. Thetheoretical and experimental results are consistent within $20\%$. We introducetwo correction factors to take into account the non-sphericity of the particleand the inclusions of air bubbles inside the particle, and reach quantitativeagreement. With these corrections, the indirect measurement of the radiusshrinking rate deduced from the position measurement is also in agreement withthe model. We discuss other correction factors, and explain why there arenegligible in the present experiment. We also compute the effective Sherwoodnumber as a function of an effective P\'eclet number.

Sedimentation of a single soluble particle at low Reynolds and high P\'eclet numbers