A one-sided direct forcing immersed boundary method using moving least squares

This paper presents a one-sided immersed boundary (IB) method using kernel functions constructed via moving least squares (MLS) method. The resulting kernels effectively couple structural degrees of freedom to fluid variables on only one side the fluid-structure interface. reduces spurious feedback forcing and internal flows that are typically observed in IB models use isotropic structure both sides developed here extends original MLS methodology introduced by Vanella Balaras (2009) [27]. Prior IB/MLS methods have used coupled interfacial freedom. approach converts cubic spline weights employed reconstruction into an function satisfies particular discrete moment conditions. shows same can be construct (kernel referred as generating literature). We also examine performance new for family Peskin. It is demonstrated construction tends generate non-monotone interpolation with large over- undershoots. present two simple weight shifting strategies positive monotone, which enhances stability methodology. Benchmark cases test order accuracy verify simulations three spatial dimensions. simulate flow over Ahmed car model, highlights applicability this modeling complex engineering flows.