Application of single blow technique for heat transfer measurement in packed bed of carrot.

The non-invasive measurement of the mean heat transfer coefficient for the packed bed of fruits and vegetables may be thought as still open issue. There is a clear need for the assessment of heat transfer conditions for various types of fruits and vegetables in order to accurately predict the thermal load that is necessary to select refrigeration equipment for cold storage chamber. Additionally, there is significant development in numerical modelling of heat and mass transfer processes in cold storage chambers for fruits and vegetables which requires precise heat transfer description. The theoretical basis for the indirect measurement approach of heat transfer coefficient for the packed bed of vegetables that is based on single blow technique is presented and discussed in the paper. The testing stand consisted of a dedicated experimental tunnel along with auxiliary equipment and measurement system are presented. The geometry of the tested packed bed of vegetables was presented. Selected experimental results of heat transfer and pressure drop are presented and discussed for the packed bed of carrot. These results were presented as dimensionless relationships.