Exergetic Analysis of Textile Convective Drying with Stenters by Subsystem Models: Part 2 - Parametric Study on Exergy Analysis

In this study, the effects of exhaust air humidity ratio, the residual moisture content of fabric outlet, and the temperature of the drying air on the exergy destruction and efficiency of stenters were investigated. The exergy efficiencies of the direct gas heated stenter (DGHS) and hot oil heated stenter (HOHS) were calculated to be varying from 8.5 to 17.5% and from 6.8 to 14.0%, depending on the exhaust air humidity ratio, respectively. The increase in the drying air temperature led to an increase in the exergy efficiency, especially in the constant rate and second rate period of the drying. On the other hand, the application of the gradual temperature method caused the highest total exergy efficiency due to the highest drying rates in the first chambers where considerably high air temperatures were set. Overdrying resulted in the higher irreversibility due to the increase in the fuel consumption in the falling rate period of drying. Thus, the exergy efficiency decreased drastically.