This paper deals with the transport of solid particles in pneumatic conveying systems, namely a 5 m horizontal pipe, a 90 degrees bend and 5 ma vertical pipe. The pipe diameter is 150 mm in all cases and the average conveying velocity is 27 m/s. Three-dimensional stationary numerical computations were performed by the Euler/Lagrange approach in connection with the k-epsilon turbulence model accounting for full two-way coupling. Particle transport is calculated by considering all the relevant forces (including drag, gravity and transverse lift forces) and dispersion due to turbulence. Particle-wall collisions and wall roughness are modelled according to Sommerfeld and Huber [1] and inter-particle collisions are described by the stochastic modelling approach of Sommerfeld [2]. The objective of the present contribution is to demonstrate the capability of this computational approach for accurately predicting more complex pneumatic conveying systems where the transported powder has a rather wide size distribution. In particular the effect of inter-particle collisions will be demonstrated. As known from many single-phase studies a secondary flow is developing along the pipe bend. Since in the present study rather small glass powder is considered (i.e. 15 mu m

Keywords:Euler-Lagrange approach;Pneumatic conveying;Wall roughness;Inter-particle collisions;Segregation phenomena;Pressure drop