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Implementation and Demonstration of a Boundary Condition Wall Function for Direct Precipitation Fouling CFD Modelling


In a previous paper we developed a generic modelling framework, for the diffusive mass transport through the turbulent boundary-layer of multi-component, reactive flows where one or more species may deposit on the wall. In the current paper, we describe the implementation of the modelling framework as a mass transfer wall function for coarse grid CFD modelling of direct precipitation fouling. The wall-function is formulated as a sub-grid model, where the simplified 1-dimensional governing equations are solved perpendicularly to the wall. This enables us, in principle, to model complex heat-exchanger geometries in two or three dimensions, since we reduce the computational cost of resolving the fine length-scales at which the boundary layer mass-transfer is determined. The mass-transfer wall function is implemented as a user-defined function (UDF) in the commercial CFD software ANSYS Fluent. To demonstrate the capabilities of the wall-function, it is employed on an axisymmetrical reactor geometry wherein a semi-artificial, 4-component, ideal mixture of perfect gasses flows. One of the components, namely the reaction product of two of the other components, can sublimate and deposit on the walls of the reactor.


Academic lecture


  • Research Council of Norway (RCN) / 226210




  • SINTEF Industry / Metal Production and Processing
  • Norwegian University of Science and Technology

Presented at

ICMF 2016 International Conference on Multiphase Flow




22.05.2016 - 27.05.2016



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