Turbulent suppression of spinodal decomposition

Light scattering experiments reveal a strong suppression of phase separation near the critical point of a vigorously stirred binary liquid mixture. For stirring Reynolds numbers R ranging from 6.0 ×{} 10³ to 4.5 ×{} 10³, the apparent critical temperature is depressed by {~}1 mK to {~}50 mK. This temperature depression ΔTc^' can be fitted to a power law ΔTc^'~R^λ where λ~2. The magnitude of ΔTc^' is consistent with simple models which attribute the effect to the suppression of composition fluctuations by shear; however, these models predict λ0.80 in contrast to the observed value of {~}2. Below the apparent critical temperature the turbidity τ changes significantly throughout a temperature range of tens of millikelvin following a power law τ∝(Tc-T)^ζ where ζ increases from {~}1 to {~}6 as R is increased.