Modeling of high power ultrasound-assisted tea drying process

Document Type : Research Paper


1 Assistant Professor, Department of Mechanical Engineering of Agricultural Machinery, Faculty of Agriculture, Ilam University

2 Master of Science, Department of Mechanical Engineering of Agricultural Machinery


Tea is one of the most important medicinal plants which have a considerable effect on the treatment of cardiovascular disease and cancer. The drying process of tea leaves is carried out by hot air flow which consumes high level energy. The aim of the recent research was to investigate the procedure of high power ultrasound-assisted drying process of tea leaves. Hybrid variety of Chinese tea was used for this target. All pre-drying process experiments were utilized in an ultrasonic bath (70 W and 28 KHz) and four levels of sonicated time (10, 20, 40 and 60 min). Five thin-layer drying models were fitted to the samples moisture ratio. Page model was found as the best to describe the behavior of ultrasound-assisted drying process of tea leaves in accordance with χ2, R2 and RMSE data. The confirmed model in this research is suitable for the simulation of ultrasound-combined drying systems.


Main Subjects

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Volume 46, Issue 4 - Serial Number 4
January 2016
Pages 363-369
  • Receive Date: 27 December 2014
  • Revise Date: 03 March 2015
  • Accept Date: 29 June 2015
  • First Publish Date: 22 December 2015