Asymptotic behavior of the steady Prandtl equation

We study the asymptotic behavior of Oleinik’s solution to steady Prandtl equation when outer flow $$U(x)=1$$ . Serrin proved that converges famous Blasius $${\bar{u}}$$ in $$L^\infty _y$$ sense as $$x\rightarrow +\infty $$ The explicit decay estimates $$u-{\bar{u}}$$ and its derivatives were by Iyer (ARMA 237,2020) initial data is a small localized perturbation profile. In this paper, we prove estimate $$u-\bar{u}$$ for general with exponential decay. also has an additional concave assumption. Our proof based on maximum principle techniques. key ingredient find series barrier functions.