DOI: 10.1615/TSFP5
STUDYING STREAMWISE ROTATION VARIATIONS OF A TURBULENT CHANNEL FLOW USING DIRECT NUMERICAL SIMULATION AND COHERENT VORTEX EXTRACTION
ABSTRACT
In this contribution a study of a turbulent channel flow rotating about the streamwise direction is presented by using direct numerical simulation (DNS). The theory giving a theoretical basis for the mean flow is based on the investigations of Oberlack et al. (2006) employing symmetry group theory. It was found both in DNS and in the theory that a cross flow in the spanwise direction is induced. A series of DNS has been conducted at Reynolds number Reτ = 180 for both the non-rotating case and different rotation numbers up to Ro = 100 to examine the effects of rotation. A further purpose of this paper is to investigate the effects of the structures of the vorticity fluctuations. Hence, the coherent vortex extraction (CVE) algorithm based on the orthogonal wavelet decomposition of vorticity is applied to six selected vorticity fluctuation fields.