Closure of two-dimensional turbulence: the role of pressure gradients.
Inverse energy cascade regime of two-dimensional turbulence is investigated by means of high resolution numerical simulations. Numerical computations of conditional averages of transverse pressure gradient increments are found to be compatible with a recently proposed self-consistent Gaussian model. An analogous low-order closure model for the longitudinal pressure gradient is proposed and its validity is numerically examined. In this case numerical evidence for the presence of higher-order terms in the closure is found. The fundamental role of conditional statistics between longitudinal and transverse components is highlighted.
Boffetta
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G
Dipartimento di Fisica Generale and INFM, Università di Torino, Via Pietro Giuria 1, I-10125 Torino, Italy.
Cencini
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M
Davoudi
J
J