Abstract:
The purpose of this research aimed to study and build mathematical modeling for steam dryer system with forced convection heat transfer. The model was analyzing the capacity of the dryer, temperature prediction, humidity ratio, and heat transfer rate of a banana. Model was used three drying pressure level at 0.5, 1, and 1.5 barg with forced convection heat transfer. The steam boiler had productive steam capacity at 200 kg/hr for heat exchanger between air and steam inside the dryer. The capacity's dryer was 0.75 m3 made from stainless steel with diameter of 2.54 cm. There are two tube rows screw exchanger fin installed by sequence tube method. According to analysis, the dryer pressure was at 0.5, 1, and 1.5 barg. The efficiency of the dryer was 92.90%, 93.05% and 94.68%, respectively. The most percentage of effectiveness of the heat exchanger was at 80.94%, 71.93% and 83.34%, respectively. The experiment shown that banana drying process revealed an appropriate condition of steam pressure was at 0.5 barg with average temperature between 70?C and 80?C, with 90% of return flow rate. The mathematical modeling predict to valuable heat transfer rate at 0.5, 1, and 1.5 barg with heat exchanger rate at 4.78, 4.62 and 4.28 kW, respectively. From results of comparison between experiment and mathematical modeling trend to go in the same way with error no more than 13 %.