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Abstract: A model for particle-level simulation of fiber suspensions has been used to simulate paper sheet forming on a roll–blade former. The fibers were modeled as chains of fiber segments, flowing and interacting with the medium and with each other. The incompressible three-dimensional Navier–Stokes equations were used to describe the fluid motion. Real pulps were analyzed to provide raw material data for the simulations. Dewatering was simulated by moving two model forming fabrics toward each other through a fiber suspension. Close examination of the dewatering process revealed that no large concentration gradients develop through the thickness of the pulp suspension. In this sense, twin-wire dewatering does not resemble a filtration process. The effects of the jet-to-wire speed difference on the network structure of the paper were investigated. The structural features of interest were fiber orientation anisotropy, mass density distribution and three-dimensionality of the fiber network. It was demonstrated that these simulated structural features were at least in qualitative agreement with experimental data found in the literature. [Copyright &y& Elsevier]