In this paper are presented PIV measurements of turbulent pipe flow at bulk Reynolds numbers Re _D between 3.4 × 10 ⁵ and 6.9 × 10 ⁵ . So-called single-pixel correlation is applied that yields a superior spatial resolution that is slightly larger than the equivalent size of a pixel in the flow. The location and shape of the averaged correlation peak give the mean velocity and normal and Reynolds stresses. A novel aspect of the single-pixel correlation approach is the extension to determine the 2-point spatial correlation of the velocity fluctuations and the spectrum of the longitudinal velocity fluctuations. Detailed results are presented for Re _D = 4.98 × 10 ⁵ , corresponding to a shear Reynolds number Re _τ = 10.3 × 10 ³ , with a spatial resolution in wall units of Δy⁺ = 19.

In this paper we present PIV measurements of turbulent pipe flow at Reynolds numbers between 3.4×10⁵ and 6.9×10⁵. We apply a so-called 'single-pixel correlation' that yields a superior spatial resolution (Westerweel et al., 2004). We use the location and shape of the averaged correlation peak to obtain the mean velocity and normal and Reynolds stresses (Scharnowski et al., 2012). A novel aspect of the single-pixel correlation approach is the extension to determine the spatial correlation of the velocity fluctuations. In this paper we present the results for Re = 4.98×10⁵, corresponding to a shear Reynolds number Re_τ = 10.3×10³, with a spatial resolution of ∆y⁺ = 18.