Vortex flows impart chirality-specific lift forces

Area of Science:

• Fluid dynamics
• Chirality studies
• Separations science

Background:

• Vortex flows' ability to discriminate between chiral molecules is debated.
• Previous studies lacked experimental control and were affected by instrumental artifacts.
• The interaction between vortex flows and stereoisomers remains unresolved.

Purpose of the Study:

• To investigate the interaction between macroscopic vortex flows and chiral objects.
• To resolve the controversy surrounding vortex-driven chiral discrimination.
• To develop a quantitative model for chirality-specific forces in shear flows.

Main Methods:

• Utilizing a Taylor-Couette cell as a model experimental system.
• Implementing macroscopic vortex flows to study chiral object behavior.
• Developing a quantitative hydrodynamic model for non-linear shear flows.

Main Results:

• Chiral objects in a Taylor-Couette cell experience a chirality-specific lift force.
• This force is directed parallel to the shear plane, differing from prior observations.
• A hydrodynamic model explains chirality-specific motion via shear-induced rotation and orbital translation.

Conclusions:

• Macroscopic vortex flows can exert chirality-specific forces on objects.
• The findings provide a mechanistic understanding of chiral discrimination in shear flows.
• This research suggests potential for micro- and nanoscale chiral separation using rotating flows.