Design, construction and evaluation of a new laboratory convective dryer using CFD
Vouros, Alexandros
Margaris, Dionissios
Bardakas, Achilleas
Tzempelikos, Dimitrios
Filios, Andronikos
Βούρος, Αλέξανδρος
Φιλιός, Ανδρόνικος
Μάργαρης, Διονύσιος
Τζεμπελίκος, Δημήτριος
Μπαρδάκας, Αχιλλέας
In order to overcome the lack of experimental data in the open literature and the necessity to validate numerical models, as well as increase the efficiency of the drying process, a new laboratory
convective (LC) dryer has been designed, constructed and equipped with an integrated measurement and automated control instrumentation. The main sections of the LC dryer, which can be
arranged for operation in a closed or open circuit mode through
manually controlled dumpers, are the vertical flow drying chamber,the tube heat exchanger, the thermal boiler and finally the fan - motor with a smooth speed control unit. The experimental facility tested and
monitored the moisture content removal of horticultural and
agricultural products. The current paper outlines the methodology
applied for the design and optimization of the LC dryer, which has
been achieved through the analysis of the flow field by means of
computational fluid dynamics (CFD). The prediction of the 3d flow
problem was accomplished through the solution of the steady-state
incompressible, Reynolds-Averaged Navier-Stokes (RANS)
equations with the incorporation of the standard k-ε turbulence model. The measurement and control instrumentation with the inclusion of the innovative, pc-controlled, 3d traverse system that
serves detailed surveys of the temperature and velocity inside the
drying chamber, are also discussed. The performance test and
evaluation of the LC dryer was conducted using quince slices as a test material at an average temperature of 60oC and air at 2 m/s into the drying chamber.