Effects of thermal boundary conditions on the performance of spray dryers

verfasst von: Sara Moradi Maryamnegari, Ali Ashrafizadeh, Egbert Baake, Mattia Guglielmi
Abstract: In this paper, three kinds of wall conditions are numerically simulated to investigate deposition, powder recovery and energy aspects of spray dryers. A co-current dryer with a pressure nozzle is chosen as a base dryer and two dryers with fully insulated, and cooled walls are compared with the base one. Governing equations of a transient flow field are solved through the Eulerian approach, while Lagrangian particle tracking predicts particles’ motion. The sticky point curve is employed as a criterion of bouncing or stickiness to model the deposition pattern of skim milk particles on the surfaces. Results show that the spray dryer with cooled walls has better deposition characteristics, while the dryer with insulated surfaces works with higher drying efficiency. Overall, it is observed that the wall conditions can be changed to improve the drying efficiency and wall deposition. However, changing the thermal boundary conditions does not seem to be effective in improving the powder recovery.
Organisationseinheit(en): Institut für Elektroprozesstechnik
Externe Organisation(en): K.N. Toosi University of Technology
Typ: Artikel
Journal: Journal of food engineering
Band: 338
ISSN: 0260-8774
Publikationsdatum: 02.2023
Publikationsstatus: Veröffentlicht
Peer-reviewed: Ja
ASJC Scopus Sachgebiete: Lebensmittelwissenschaften
Elektronische Version(en): https://doi.org/10.1016/j.jfoodeng.2022.111250 (Zugang: Geschlossen)

BibTeX

@article{a4372398953b421b9d16c728600af77b,
title = "Effects of thermal boundary conditions on the performance of spray dryers",
abstract = "In this paper, three kinds of wall conditions are numerically simulated to investigate deposition, powder recovery and energy aspects of spray dryers. A co-current dryer with a pressure nozzle is chosen as a base dryer and two dryers with fully insulated, and cooled walls are compared with the base one. Governing equations of a transient flow field are solved through the Eulerian approach, while Lagrangian particle tracking predicts particles{\textquoteright} motion. The sticky point curve is employed as a criterion of bouncing or stickiness to model the deposition pattern of skim milk particles on the surfaces. Results show that the spray dryer with cooled walls has better deposition characteristics, while the dryer with insulated surfaces works with higher drying efficiency. Overall, it is observed that the wall conditions can be changed to improve the drying efficiency and wall deposition. However, changing the thermal boundary conditions does not seem to be effective in improving the powder recovery.",
keywords = "CFD simulation, Deposition, Energy performance, Skim milk, Spray drying, Sticky point curve",
author = "{Moradi Maryamnegari}, Sara and Ali Ashrafizadeh and Egbert Baake and Mattia Guglielmi",
year = "2023",
month = feb,
doi = "10.1016/j.jfoodeng.2022.111250",
language = "English",
volume = "338",
journal = "Journal of food engineering",
issn = "0260-8774",
publisher = "Elsevier Ltd.",
}