Application of mapping closure to non-Gaussian velocity fields

An attempt is made to assess the mapping closure for turbulent velocity fie lds with non-Gaussian probability density functions (PDFs). The a priori as sumption of the Gaussian velocity statistics is not made in the present map ping closure, which generalizes the results for the Burgers turbulence by K raichnan [Phys. Rev. Lett. 65, 575 (1990)] and Gotoh and Kraichnan [Phys. F luids A 5, 445 (1993)]. The PDFs calculated from the mapping closure are co mpared to the results obtained from the direct numerical simulation for non -Gaussian initial fields. The statistics of second- and higher-order deriva tive terms are discussed also. (C) 1999 American Institute of Physics. [S10 70-6631(99)00908-3].