On Meshfree GFDM Solvers for the Incompressible Navier-Stokes Equations
For researchers using meshfree methods for fluid dynamics, this work addresses a known accuracy bottleneck in mass conservation.
The paper identifies drawbacks of existing meshfree GFDM schemes for incompressible Navier-Stokes equations, particularly inaccurate mass conservation, and proposes a modified monolithic scheme that improves velocity divergence approximation, demonstrating higher accuracy in numerical comparisons.
Meshfree solution schemes for the incompressible Navier--Stokes equations are usually based on algorithms commonly used in finite volume methods, such as projection methods, SIMPLE and PISO algorithms. However, drawbacks of these algorithms that are specific to meshfree methods have often been overlooked. In this paper, we study the drawbacks of conventionally used meshfree Generalized Finite Difference Method~(GFDM) schemes for Lagrangian incompressible Navier-Stokes equations, both operator splitting schemes and monolithic schemes. The major drawback of most of these schemes is inaccurate local approximations to the mass conservation condition. Further, we propose a new modification of a commonly used monolithic scheme that overcomes these problems and shows a better approximation for the velocity divergence condition. We then perform a numerical comparison which shows the new monolithic scheme to be more accurate than existing schemes.