せん断乱流場における Lagrange 相関関数

Abstract

This paper deals with a longitudinal mixing of particles which are instantaneously releasedin a bounded turbulent shear flow. The movements of particles are described in view of theLagrangian particle analysis. The similarity of concerned phenomena to the turbulent diffu-sion by continuous movements in a uniform turbulent flow is studied. The discrepancy oftwo phenomena is also shown with some discussions. In the mixing the Lagrangian auto-correlation function plays the most important role. Some auto-correlation functions in aturbulent shear flow are introduced and their dependency on a released position and traveltime is discussed. The discussion gives useful information of estimating the Lagrangianauto-correlation function in a turbulent shear flow. Finally, the model of the Lagrangianauto-correlation function proposed by the authors in the other paper is referred, and thegeneral features of longitudinal mixing given by the proposed model are compared withthe past knowledge experimentally obtained.