We present an enhanced lattice Boltzmann method for simulating viscoelastic fluid flows at high Weissenberg numbers. The approach utilizes dual two-relaxation-time regularized models to separately handle hydrodynamic and conformation tensor fields, with direct incorporation of viscoelastic stress to avoid gradient calculations.  A key innovation is the introduction of a conservative boundary treatment scheme that significantly improves computational stability. The method demonstrates superior performance in benchmark tests including four-roll mill configurations, high Weissenberg number Poiseuille flows, and complex curved boundary geometries, showing marked improvements in numerical accuracy and robustness compared to conventional approaches.
 

Lattice Boltzmann method, high Weissenberg number problem, viscoelastic flows