Axisymmetric spheroidal squirmers and self-diffusiophoretic particles

Area of Science:

• Fluid dynamics
• Microhydrodynamics
• Chemical physics

Background:

• Spherical 'squirmer' models are well-established for microswimmer analysis.
• Understanding non-spherical microswimmer dynamics is crucial for complex biological and synthetic systems.
• Low Reynolds number flows govern the motion of micro-organisms and particles.

Purpose of the Study:

• To investigate the hydrodynamic flow and motion of a spheroidal, axisymmetric squirmer.
• To analytically determine the relationship between squirming modes and resulting fluid dynamics for spheroids.
• To extend findings to self-phoresis of spheroidal, chemically active particles.

Main Methods:

• Exact analytical solution for fluid dynamics.
• Analysis of low Reynolds number hydrodynamic flow.
• Application of the phoretic slip approximation.

Main Results:

• For spheroidal squirmers, individual squirming modes distinctly influence either velocity or stresslet, unlike spherical squirmers.
• Each mode's contribution to squirmer velocity or induced flow stresslet is uniquely determined.
• The analytical framework is directly applicable to self-phoretic spheroidal particles.

Conclusions:

• The distinct mode contributions for spheroidal squirmers offer a new understanding of microswimmer propulsion and flow generation.
• This work provides a foundational model for non-spherical microswimmer behavior and self-phoresis.
• The findings are relevant for designing and analyzing micro-robots and understanding biological microswimmers.