caa a22 4500 606197338 CHVBK 20210128100928.0 cr unu---uuuuu 210128e20150601xx s 000 0 eng 10.1007/s00348-015-1995-6 doi (NATIONALLICENCE)springer-10.1007/s00348-015-1995-6 Drag of a turbulent boundary layer with transverse 2D circular rods on the wall [Elektronische Daten] [Md Kamruzzaman, L. Djenidi, R. Antonia, K. Talluru] In this paper, we present the results of a turbulent boundary layer developing over a rod-roughened wall with a spacing of $$\lambda /k = 8$$ λ / k = 8 ( $$\lambda$$ λ is the spacing between two adjacent roughness elements, and $$k$$ k is the rod diameter). Static pressure measurements are taken around a single roughness element to accurately determine the friction velocity, $$U_\tau$$ U τ and the error in the origin, $$d_0$$ d 0 , which are the two prominent issues that surround rough-wall boundary layers. In addition, velocity measurements are taken at several streamwise locations using hot-wire anemometry to obtain $$C_\mathrm{f}$$ C f from the momentum integral equation. Results showed that both methods give consistent values for $$U_\tau$$ U τ , indicating that the contribution of the viscous drag over this rough wall is negligible. This supports the results of Perry et al. (J Fluid Mech 177:437-466, 1969) and Antonia and Luxton (J Fluid Mech 48(04):721-761, 1971) in a boundary layer and of Leonardi et al. (2003) in a channel flow but does not agree with those of Furuya et al. (J Fluids Eng 98(4):635-643, 1976). The results show that both $$U_{\tau }$$ U τ and $$d_0$$ d 0 can be unambiguously measured on this particular rough wall. This paves the way for a proper comparison between the boundary layer developing over this wall and the smooth-wall turbulent boundary layer. Springer-Verlag Berlin Heidelberg, 2015 Kamruzzaman Md Discipline of Mechanical Engineering, School of Engineering, The University of Newcastle, 2308, Callaghan, NSW, Australia aut Djenidi L. Discipline of Mechanical Engineering, School of Engineering, The University of Newcastle, 2308, Callaghan, NSW, Australia aut Antonia R. Discipline of Mechanical Engineering, School of Engineering, The University of Newcastle, 2308, Callaghan, NSW, Australia aut Talluru K. Discipline of Mechanical Engineering, School of Engineering, The University of Newcastle, 2308, Callaghan, NSW, Australia aut Experiments in Fluids Springer Berlin Heidelberg 56/6(2015-06-01), 1-8 0723-4864 56:6<1 2015 56 348 https://doi.org/10.1007/s00348-015-1995-6 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00348-015-1995-6 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Kamruzzaman Md Discipline of Mechanical Engineering, School of Engineering, The University of Newcastle, 2308, Callaghan, NSW, Australia aut NATIONALLICENCE 700 1- Djenidi L. Discipline of Mechanical Engineering, School of Engineering, The University of Newcastle, 2308, Callaghan, NSW, Australia aut NATIONALLICENCE 700 1- Antonia R. Discipline of Mechanical Engineering, School of Engineering, The University of Newcastle, 2308, Callaghan, NSW, Australia aut NATIONALLICENCE 700 1- Talluru K. Discipline of Mechanical Engineering, School of Engineering, The University of Newcastle, 2308, Callaghan, NSW, Australia aut NATIONALLICENCE 773 0- Experiments in Fluids Springer Berlin Heidelberg 56/6(2015-06-01), 1-8 0723-4864 56:6<1 2015 56 348