AN INSIDE VIEW ON IMPULSE DRYING PHENOMENA BY MODELING

摘要

This paper describes the first phase of the development of a press model calledrnEXPRESS. The model is used to support the R&D activities in Europe on improvedrnmechanical dewatering. The basis is a currently one dimensional press model describingrnthe flow phenomena in a sandwich formed by the paper web and the press felt(s). Thernmodel has been extended with an energy equation describing the heat transfer in arnheated press nip. Ultimately the model will be capable to describe the impulse dryingrnprocess.rnEXPRESS-1, the result of phase 1, has been validated with experimental data from arnpilot paper machine shoe press operated with press roll temperatures from 50°C up torn235°C. The model predictions show good agreement with the experimental data overrnthe whole temperature range.