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WOS: 000324787600060, An original model for thermodynamic analysis of a batch type fluidized bed dryer is proposed herein considering two separate systems comprised of drying air medium as a control volume and particles to be dried as a control mass. By means of the proposed model, energetic and exergetic analyses of a drying column of a batch type fluidized bed dryer are carried out as an original contribution to literature since there is no such like model in which the analyses are performed considering two separate systems. The energetic efficiencies evaluated by means of the proposed model using the data in literature are compared with those in literature and a good conformity is satisfied with an acceptable error margin of +/- 9%. A new correlation is also developed with a mean deviation of 10% in order to evaluate the energetic efficiency for not only corn drying process but also drying processes of other particles at inlet air temperature of 50 degrees C. Effects of air mass flow rate, mass of particle and ambient temperature on energetic and exergetic efficiencies are analyzed and some concluding remarks are highlighted for further studies.

In this study, plum slices were dried in three different driers (tray, fluid bed, and heat pump (HP) driers). Drying experiments were carried out at an air temperature range of 45-55 °C with an air velocity of 1.5 m/s. The performance of the driers along with their main components was evaluated and compared by using the exergy analysis method. The most important component for improving the system efficiency was determined to be the fan-heater combination for both the tray and fluid bed driers, and the motor-compressor assembly for the HP drier. The exergy loss and flow diagram (the so-called Grassmann diagram) of the driers was also presented to give quantitative information regarding the proportion of the exergy input dissipated in the various system components. Effects of the drying air temperature on the performance of the drying process were discussed. The highest exergetic efficiency values were obtained to range from 72.72 to 75.66 per cent for the HP drier, followed by the tray and fluid bed driers varying between 37.94 and 39.46 per cent, and between 22.83 and 24.07 per cent, respectively., TÜBİTAK project no. 106M482

This article deals with the exergy analysis and evaluation of broccoli in three different drying systems. The effects of drying air temperature on the exergy destruction, exergy efficiency, and exergetic improvement potential of the drying process were investigated. The exergy destruction rate for the drying chamber increased with the rise in the drying air temperature at 1.5 m/s, both in the tray and the heat pump dryer. The highest exergy efficiency value was obtained as 90.86% in the fluid bed dryer in comparison to the other two drying systems and the improvement potential rate was the highest in the heat pump dryer during drying of broccoli at the drying air temperature of 45°C and the drying air velocity of 1.0 m/s. © 2010 Taylor & Francis Group, LLC., TÜBİTAK project no: 106M482

In this study, plum slices were dried in a heat pump dryer designed and constructed in Ege University, Izmir, Turkey. Drying experiments were carried out at an air temperature range of 45-55°C. The performance of the dryer along with its main components were evaluated using an exergy analysis method. Exergy destruction and capital cost rates were used for the exergoeconomic analysis, which is based on the quantities exergy, cost, energy, and mass (EXCEM) method. Exergy destruction rates to capital cost values Rex were obtained to vary between 1.668 and 2.063 W/ USD at different drying air temperatures. Ren values were observed to range from 6.258 to 5.749 W/USD. Ren values decreased as the drying air temperature increased, contrary to Rex values. Ṙex and Ṙen values increased linearly with increasing temperature due to the loss, whereas Ṙen decreased due to the relatively higher energy utilization efficiency of the heat pump. In the compressor, Ṙen and Ṙex values decreased with the increase in the temperature contrary to the other components. Ṙex had the lowest value in the drying duct. However, in the compressor, expansion valve, and heat recovery, Ṙex values were found to be higher and should be improved in these units. © 2010 Taylor & Francis Group, LLC., TÜBİTAK project no. 106M482