CFDRC engineers are developing new software tools using wavelet-based multiresolution (MRES) technology. Wavelet based multiresolution technology provides a natural way of resolving high gradient concentrated flow features while still solving the predominantly smooth regions using coarse grids, without resorting to grid refinement or adaptation. Wavelet technology provides up to two-orders-of-magnitude reduction in grid and CPU requirements over traditional computational techniques

Complex problems with very fine flow features, such as in rotorcraft tip vortices, exhaust plume signatures, jet noise, and electronic cooling, require prohibitive levels of grid refinements for accurate solution. Wavelet technology provides a solution to this problem using a novel technology of data compression. In the wavelet method, the solution to the flowfield is stored as multi-level wavelet components in physical space. The primary solution progresses along a very coarse grid. The flow-field regularity is dynamically used to identify regions where greater grid resolution is needed such as regions of concentrated vorticity. The regions of concentrated flow structures are selectively and recursively solved in the finer grid levels. The key strength of the wavelet methods is data compression. If a data set contains fine features embedded in smooth regions, wavelets have superb efficiency in compressing such data. Furthermore, the MRES underlying structure allows the implementation of higher order spatial algorithms even though the solution data is essentially unstructured.