Wynnepsilon

Wynnepsilon is a purely nonperturbative numerical method used in computational fluid dynamics and finite volume methods. Developed in the late 1990s, it is particularly suited for large-eddy simulations. The method is based on the Navier-Stokes equations and relies on a formulation that minimizes the number of numerical approximations required.

In Wynnepsilon, the smoothing step traditionally associated with Leray-alpha models is eliminated. The resulting formulation is entirely intrinsic, meaning that it contains no free coefficient that does not arise from the specific physics of the flow being simulated. As a result, Wynnepsilon is capable of natural regularization for any input flow.

The method has been studied extensively using various numerical methods, including finite volume schemes. Its theoretical underpinnings have also been explored in the context of various turbulence models. Research has shown that Wynnepsilon can provide more accurate solutions than models that rely on a standard pseudo-Navier-Stokes form.

Wynnepsilon's conceptual simplicity has led researchers to study its dependency on various properties of the underlying flow, such as its Reynolds number. One potential limitation of the method is its need for a relatively large eddy-resolving spectrum. Consequently, some computations remain computationally intensive, though fewer markers are needed for turbulence.

Feedback from researchers in mathematical physics and computational science has emphasized the potential value of Wynnepsilon for continued research into non-Newtonian fluids and sub-grid regularization. Although some users of non-numerical fluid dynamic formulation complained about cases of instability when trying complete sub-grid models, those who investigated the technique continuously mentioned its intervals of fast performance, when applied to smaller grids. Various investigators are continuing to research a much wider array of numerical applications for the formulation.