Microscopic study of the behavior of water in a single pore under vibration to intensify drying

Abstract : A better economic performance of industrial drying consists both in product quality improvement and energy efficiency enhancement. Several technologies can be applied to intensify the drying process. This work is focused on the effect of vibration that can assist the drying through heating-up due to viscous dissipation, enhancement of liquid and vapor migration inside the porous medium and the increase of the external heat and mass transfer. However, despite previous numerical and experimental studies, the assessment of the relative importance of these intensification mechanisms has still to be improved.This work is focused on the pore scale, simulated by a capillary tube, partially filled with water subjected to sinusoidal vibrations. A full experimental device was conceived, developed and used. Thanks to a relevant image processing chain, the behavior of water inside the tube (displacement and meniscus radius), was investigated for various vibration configurations (frequency, amplitude, tube size). Experiments with both symmetrical and asymmetrical geometries are intended to mimic the moisture transfer during drying of a porous medium. Whatever the configuration, the drying intensification was clearly confirmed.For the symmetrical configuration, a new 2D dimensionless number map is set to summarize the capillary and viscous effects and thus to explain the water behavior depending on vibration conditions (tube radius, frequency and amplitude). For the asymmetrical configuration, the experimental results are discussed and compared to the simulations obtained with two computational models (a 0-D model and 1-D model). The potential of modeling was evidenced but still limited by the surrounding physical assumptions. Further developments are proposed to increase the validity range and further investigate this physical system
Complete list of metadatas

Cited literature [251 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-02275217
Contributor : Abes Star <>
Submitted on : Friday, August 30, 2019 - 3:34:29 PM
Last modification on : Sunday, September 1, 2019 - 1:09:33 AM

File

74029_CHEN_2019_archivage.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-02275217, version 1

Citation

Wangshu Chen. Microscopic study of the behavior of water in a single pore under vibration to intensify drying. Chemical and Process Engineering. Université Paris-Saclay, 2019. English. ⟨NNT : 2019SACLC054⟩. ⟨tel-02275217⟩

Share

Metrics

Record views

46

Files downloads

26