Performance Investigation of a Heat Recovery Assisted Solar Dryer for Mint Drying

Document Type : Research Paper


1 Student in Biosystems Engineering Department, Shahid Bahonar University of Kerman

2 Assistant Professor in Biosystems Engineering Department, Shahid Bahonar University of Kerman

3 Associate Professor in Biosystems Engineering Department, Shahid Bahonar University of Kerman


Drying of agricultural products is a sophisticated process with high energy consumption. Energy needed for sustainable development, is one of the biggest challenges facing humanity. The performance of a heat recovery assisted solar dryer was evaluated in this study. Drying time, collector efficiency, energy consumption, solar fraction and energy recovery fraction were investigated at different drying air temperatures (45, 55 and 65 oC) and three levels of air flow rate (0.04, 0.06 and 0.08 kg/s). The results showed that collector efficiency decreased at higher drying temperatures and lower air flow rates. Increasing the air temperature from 45 to 65 oC reduced energy consumption by 25%. Meanwhile, the air temperature rise decreased solar fraction by 24% while improved energy recovery fraction by 20%.


Main Subjects

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Volume 46, Issue 4 - Serial Number 4
January 2016
Pages 379-388
  • Receive Date: 27 January 2015
  • Revise Date: 14 May 2015
  • Accept Date: 29 June 2015
  • First Publish Date: 22 December 2015