Rapidly yawing spheroids in viscous shear flow: Emergent loss of symmetry

The paper’s multiple-scales/adjoint derivation yields the slow rotational system (3.17) with effective two-plane-symmetric Jeffery coefficients B1 = B J0(2A), B2 = −(B/2)(1 + J0(2A)), B3 = (B/2)(1 − J0(2A)), and the emergent translation V̄ with J0(A), J1(A) weights (5.7b). The candidate solution reproduces exactly these coefficients and the translation formula by an averaging approach based on e(t) ≈ R2(χ) ē and ⟨R2(χ)⟩ = diag(J0(A), 1, J0(A)), and correctly identifies the ellipsoid-consistency condition Π(1+Bk)=Π(1−Bk), with the same three special cases (A=0, B=0, or J0(2A)=0). Minor issues: the candidate’s derivation of the effective spheroidal aspect ratio contains a notational/algebraic slip en route, though the final expression agrees with the paper’s (6.2).