Mathematical modeling for drying of tomato in hybrid dryer

Abstract EN

A mathematical model was developed for a concentrative flat plate solar collector coupled with an indirect multirack type hybrid dryer.

The model was physically-based, taking into account the heat transfer in the collector and heat and mass transfer in the dryer.

One set of equations was developed to predict cover, receiver, and air temperatures in the collector.

Another set of partial differential equations was developed to predict the air and product temperatures, air humidity, and moisture content for drying of tomato halves in the hybrid dryer.

The first set of equations were solved iteratively and the second set of equations were solved numerically based on an exponential solution over the finite difference grid element using the outlet air conditions of the collector as inlet air conditions of the drying unit.

The simulated cover, air, and receiver temperatures in the collector agreed well with the measured temperatures.

Good agreements were also found between experimental and simulated air and product temperatures, air relative humidity, and product moisture content in the dryer.

This model can be used to provide design data of the solar and hybrid dryer for the drying of tomatoes as well as other fruits and vegetables.