| 1. |
- Johnson, Tomas, 1979, et al.
(författare)
-
A Multi-Scale Simulation Method for the Prediction of Edge Wicking in Multi-Ply Paperboard
- 2015
-
Ingår i: Nordic Pulp and Paper Research Journal. - 2000-0669 .- 0283-2631. ; 30:4, s. 640-650
-
Tidskriftsartikel (refereegranskat)abstract
- When liquid packaging board is made aseptic in the filling machine the unsealed edges of the board are exposed to a mixture of water and hydrogen peroxide. A high level of liquid penetration may lead to aesthetic as well as functional defects. To be able to make a priori predictions of the edge wicking properties of a certain paperboard material is therefore of great interest to the paper industry as well as to packaging manufacturers. In this paper an extended multi-scale model of edge wicking in multi-ply paperboard is presented. The geometric and physical properties of the paperboard are modeled on the micro-scale, and include fillers and fines. The absolute air permeabilities and pore size distributions are validated with experimental and tomographic values. On the macro-scale random porosity and sizing distributions, time and sizing dependent contact angles, and inter-ply dependence are modeled. Arbitrary shapes of the paperboard are handled through an unstructured 3D surface mesh. Stationary and transient edge wicking simulations are validated against experiments with excellent agreement. The simulations show that the diffusive menisci between the liquid and air phases together with the two-ply model is necessary to achieve good agreement with the transient edge wicking experiments.
|
|
| 2. |
- Mark, Andreas, 1980, et al.
(författare)
-
Modeling and Simulation of Paperboard Edge Wicking
- 2012
-
Ingår i: Nordic Pulp and Paper Research Journal. - 2000-0669 .- 0283-2631. ; 27:2, s. 397-402
-
Tidskriftsartikel (refereegranskat)abstract
- When liquid packaging board is made aseptic in the filling machine the unsealed edges of the board are exposed to hydrogen peroxide. A high level of liquid penetration may lead to aesthetic as well as functional defects. To be able to make a priori predictions of the edge wicking properties of a certain paperboard material is therefore of great interest to paper industry as well as to packaging manufacturers. The aim of this paper is to present a new analytical theory for prediction of the edge wicking properties of paperboard. The theory is based on Darcy’s law and the ideal gas law to describe the physical behavior of water flow in paperboard. The theory is compared to a recently published multi-scale framework and with pressurized edge wick experiments. The agreement is very good for paperboard samples of different sizes. The conclusion from the work is that both analytical theory and detailed simulations are useful to predict edge wicking properties of paperboard material.
|
|
| 3. |
- Mark, Andreas, 1980, et al.
(författare)
-
Multi-scale simulation of paperboard edge wicking using a fiber-resolving virtual paper model
- 2011
-
Ingår i: Progress in Paper Physics Seminar. - 9783851251630 ; , s. 41-47
-
Konferensbidrag (refereegranskat)abstract
- When liquid paperboard based package material ismade aseptic, unsealed edges of the board are exposedto a liquid front which in some circumstances may soakthe material to some extent. This is not desired since itmay lead to aesthetic as well as functional defects. Inorder to make a priori predictions of the edge wickingproperties of a given paper material, something whichis of great interest to paperboard industry as well aspackaging manufacturers, micro simulations are required.To calculate the penetration of fluid in the open edgeof a paper sheet a multi-scale framework is developed.On the fiber micro-scale, virtual paper models are generatedin PaperGeo [6]. In IBOFlow [7] a pore morphologymethod is used to calculate capillary pressurecurves, and the active pores one-phase flow simulationsare performed for relative permeabilities. Theresult is a database of capillary pressure curves andrelative permeabilities as functions of saturation andporosity. The database is used as an input for a twophaseflow simulation on a 2D virtual macro sheet tocalculate the penetration of fluid in the paper. Themulti-scale framework is validated against pressurizededge wick measurements with good agreement.
|
|
