Basis operator bispectral analysis
نویسندگان
چکیده
A new procedure for calculating model coefficients from fluctuation data for fully developed turbulence is derived. This procedure differs from previous related methods in that it is constructed in a spatial rather than spectral representation. This has a number of advantages, such as reduced data set requirements, ability to represent spatially inhomogeneous systems such as the ones with curvature or zonal flows, and ability to use data from experimental diagnostics with limited spatial resolution. In this method, the model equation is represented as a linear superposition of linear and nonlinear differential operators. The coefficients of this superposition are calculated using a least-squares method. This method has been tested on simulations of fully developed two dimensional turbulence and compared to previous methods. © 2009 American Institute of Physics. DOI: 10.1063/1.3093844
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