CFD evaluation of droplet drying models in a spray dryer fitted with a rotary atomizer

Meng Wai Woo, Wan Ramli Wan Daud, Arun Shadashiv Mujumdar, Zhong Hua Wu, Meor Zainal Meor Talib, Siti Masrinda Tasirin

Research output: Contribution to journalArticle

69 Citations (Scopus)

Abstract

Computational fluid dynamics (CFD) modeling of spray dryers requires a simple but sufficiently realistic drying model. This work evaluates two such models that are currently in discussion; reaction engineering approach (REA) and characteristic drying curve (CDC). Two versions of the CDC, linear and convex, drop in drying rate were included. Simulation results were compared to the overall outlet conditions obtained from our pilot-scale experiments. The REA and CDC with a linear drop in drying rate predicted the outlet conditions reasonably well. This is contrary to the kinetics determined previously. Analysis shows that the models exhibit different responses to changes in the initial feed moisture content. Utilizing different models did not result in significantly different particle trajectories. This is due to the low relaxation time of the particles. Despite the slight differences in the drying curves, both models predicted similar particle rigidity depositing the wall. For the first time in a CFD simulation, the REA model was extended to calculate the particle surface moisture, which showed promising results for wet particles. Room for improvement was identified when applying this concept for relatively dry particles.

Original languageEnglish
Pages (from-to)1180-1198
Number of pages19
JournalDrying Technology
Volume26
Issue number10
DOIs
Publication statusPublished - 2008

Fingerprint

atomizers
drying apparatus
Atomizers
computational fluid dynamics
drying
sprayers
Drying
Computational fluid dynamics
evaluation
engineering
curves
outlets
Moisture
particle trajectories
rigidity
moisture
Rigidity
Relaxation time
moisture content
simulation

Keywords

  • CFD
  • Droplet drying model
  • Rigidity
  • Spray drying

ASJC Scopus subject areas

  • Chemical Engineering(all)
  • Physical and Theoretical Chemistry

Cite this

CFD evaluation of droplet drying models in a spray dryer fitted with a rotary atomizer. / Woo, Meng Wai; Wan Daud, Wan Ramli; Mujumdar, Arun Shadashiv; Wu, Zhong Hua; Meor Talib, Meor Zainal; Tasirin, Siti Masrinda.

In: Drying Technology, Vol. 26, No. 10, 2008, p. 1180-1198.

Research output: Contribution to journalArticle

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