Particles effect in a turbulent gas-particle flow within a 90-degree bend

Simultaneous measurements of both the carrier gas phase and the dispersed particulate phase were carried out inside a curved 90o duct bend. These measurements were undertaken in order to investigate the effects of dilute turbulent particulate flows on the gas phase and vice versa. The investigations were carried out experimentally in the Advanced Laser Diagnostic Laboratory at CSIRO Division of Minerals using 2D Phase Doppler Anemometry (PDA). The main objective of the current study is to decipher the effect of streamwise and transverse velocities of the particles on the gas phase. This study has also been carried out with the view of obtaining robust experimental data for developing (and validating) accurate CFD models. Glass spheres with mean diameter of 77ìm were used to represent the solid phase, while the carrier gas phase has a working Reynolds number of Re=1.0 x 105 (bulk velocity Uo=10ms-1). The gas phase results were analysed as both clean gas (without any particles) and unclean gas (with particles). The unclean gas results were separated from the particles based on their size in the postprocessing step of the laser data. It is observed that the streamwise and the transverse velocities of the unclean gas phase `lagged¿ behind the clean gas velocities from the mid section of the duct towards the inner bend wall. Also, the same feature is observed along the vertical duct past the 90o bend. This phenomenon is mainly attributed to the effect of the particles drag on the continuous gas phase.