Some properties of truncated turbulence signals in bounded shear flows

Earlier measurements of the contribution of four distinct classes of motions, i. e. (u 0), (u > 0, v 0, v > 0), to the Reynolds stress - uv in the wall region of a bounded turbulent shear flow have been extended. These classes were obtained by truncating the u and v signals about zero. Various statistical properties of the truncated streamwise and normal velocity components u and v and of their product uv have been determined in an attempt to characterize quantitatively the motions in this flow. Average values and probability density distributions both of the truncated and untruncated signals have been taken.