| 초록 |
There have been several attempts to simulate a viscoelastic fluid flow in the high Weissenberg number problem (HWNP). Applying various stabilization methods to the equation of motion and viscoelastic constitutive equations that adjust the stress and add artificial numerical convection term could help to simulate the viscoelastic fluid flow with increasing the Weissenberg number (We), but not fully enough to interpolate the exponentially increasing stress in HWNP. Furthermore, unlike the case of a Newtonian fluid, mesh refinement could not help for the viscoelastic fluid as it can possibly violate the positive definiteness of conformation tensor. Fattal and Kupfermann (2004) developed the log conformation reformulation (LCR) to solve the log-converted stress using a polynomial interpolation function. In this study, we attempt to develop the analysis of HWNP with LCR for the Leonov model, which is known as the only viscoelastic constitutive equation showing non-vanishing N2 in simple shear flow by Kwon and Leonov (1995). Also, we compare the stress tensor data in the same We, and the limitation of it when stabilization methods (DEVSS-G/SUPG) or LCR are applied. |
