Determination of Air Flow Pattern During Solar Drying of Fruits Using a Low Range Air Speed Sensor

The solar drying is an attractive drying method in a sense of low temperature dehydration process which is useful for the dry product quality and energy saving including the environmental issues. Moreover, it can be applied in small scale (family size farms) which is in accordance with the distributed resource approach of the sustainable development. In the course of the recent research numerous drying experiments were elaborated with the solar drying of biomaterials, mainly with fruits. Beside the measurements, the modelling of the drying process was also investigated. Special attempt was carried out developing a low range air speed sensor (for measuring natural ventilation during the solar drying process) which can be used with a usual data logging system. After choosing the working principle a one dimensional prototype of the sensor was developed and constructed. Based on the measurements the optimal setting of the sensor was determined. Additionally, the set-up of a two-dimensional sensor prototype is also presented, along with its first measurement results.