(144a) Modification of the Billet and Schultes-Model for the Hydraulic Modelling of Random and Structured Packing

If a new packing is developed and introduced to the market, a reliable calculation of the properties is hard to perform as the known correlations are not able to consider all the special influences of the geometrical properties of a packing. Therefore, the published hydraulic models only work acceptable for validated packing types.

To ensure a good rating of a newly developed packing for different application areas, a reliable forecast of the hydraulic properties has to be guaranteed. Therefore, the following models from literature have been examined on their ability to model a newly developed grid-structured packing: SRP-Model, Delft-Model, NNA-Model of Piché et al., Billet and Schultes-Model, Maćkowiak-Model and Stichlmair-Engel-Model. Unfortunately, none of them is able to calculate the hydraulic properties of the grid structured packing satisfactorily. The best modelling results could be reached with the model of Billet and Schultes. As a result of that and the fact that the Billet and Schultes-Model is applicable for structured as well as for random packing, it was examined more closely. Due to a relatively simple but physically justified modification of the Billet and Schultes-Model good modelling results can be reached.

Furthermore, it can be shown that this adjustment also leads to a better prediction of the wet pressure drop of further examined packing types. Moreover, the area of validity of the Billet and Schultes-Model of 0.61 – 60 m³/(m²*h) can be extended to an irrigation density of 120 m³/(m²*h) for the calculation of the wet pressure drop.