## MODEL OF THE SURFACE OF EQUAL CONCENTRATION IN A TURBULENT REACTING FLOW

Yu. V. Zhukova and V. A. Sosinovich UDC 532.517.4 Statistical data on the scalar-field gradient obtained by means of direct numerical simulation of turbulence is used in the present paper to predict the form of the specific area of the isoscalar surface at different stages of evolution of a turbulent flow. From the available literature data on the conditional scalar dissipation rate a suggestion of the form of typical realizations of the turbulent field at different stages of its evolution is made and on this basis the form of the scalar gradient probability density on the isoconcentric surface is proposed. Using this quantity and the idea that the turbulent scalar field is multiscale in nature, it is possible to calculate the dependence of the specific area of equal concentration on the scalar value at the initial, intermediate, and final stages of turbulent mixing. The results of the present work are compared with the results of other theoretical approaches to the calculation of the surface area of equal concentration. A. V. Luikov Heat and Mass Transfer Institute, National Academy of Sciences of Belarus, Minsk, Belarus; email:svaturb@ns1.hmti.ac.by. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 75, No. 3, pp. 51-62, May-June, 2002. Original article submitted July 11, 2001. JEPTER74920200216 JEPTER7492016