Pressure losses in pipe bends reduce the energy efficiency of piping systems and are of particular importance in applications such as engine intake systems. Although dimpled surfaces have demonstrated the potential to reduce drag in straight pipes and flat plates, their application to pipe bends has not yet been widely investigated. This work presents the development and experimental characterization of a compressed-air test facility designed to provide fully developed turbulent inflow conditions for future investigations of pressure loss reduction in dimpled 90° pipe bends. To characterize the developed test facility, outlet velocity profiles were measured at Reynolds numbers of Re = 28300 and 50000 using pressure probes and Particle Image Velocimetry (PIV). For both Reynolds numbers tested, the horizontal and vertical velocity profiles exhibited a symmetric distribution, and close agreement was observed between the experimental measurements and the turbulent flow model, confirming fully developed turbulent flow conditions at the pipe outlet. These measurements provide the experimental basis for the subsequent design and evaluation of dimpled elbow configurations.     «

Pressure losses in pipe bends reduce the energy efficiency of piping systems and are of particular importance in applications such as engine intake systems. Although dimpled surfaces have demonstrated the potential to reduce drag in straight pipes and flat plates, their application to pipe bends has not yet been widely investigated. This work presents the development and experimental characterization of a compressed-air test facility designed to provide fully developed turbulent inflow condition...     »