A Flexible Approach for Modelling Flow in Multi-Component Blade Formers

Authors: Holmqvist, J.F., Dahlkild, A. A., Norman, B.
Document Type: Article
Pubstate: Published
Journal: Nordic Pulp and paper research Journal
Volume: Vol. 21, No.1   73-81
Year: 2006


The internal structure of the fibre network constituting a paper is to a dominating extent determined in the forming zone of the paper machine. In this article we present a method for modelling the pressure distributions in blade forming sections, which is commonly considered to be a key quantity of the process. The ambition is to obtain a tool by which the interaction between the different components of blade sections can be studied. It is achieved by defining modules out of which arbitrary sections can be constructed. The modules are solved independently and matched to each other iteratively. Keeping the interface between the modules simple provides great flexibility in the modelling. By virtue of a slenderness assumption, the equations governing each module can be reduced to one-dimensional form, hence limiting the computational work and permitting systems of many components to be studied. Dimensionless numbers defining the problem are identified, and the magnitude of the nonlinear effects are estimated. Simulations are presented that illustrate the potential of the method.