A New Moisture-Measurement Technique for Drying Beds of Loose Textile Fibers

Abstract

Investigations are reported into the measurement of the fall in temperature (ΔT) in a stream of hot air on passing through a bed of loose wool fibers and the relationship of this temperature change to the average regain of the wool (R). A mathematical basis for the nature of the relationship between ΔT and R has been established, and an empirical equation is developed and-used to calculate the wool regain in a batch dryer from measurements of ΔT. The significance and effect of changes in such drying pa meters as wool bed thickness, pressure drop across the bed, fineness of the wool, and the inlet temperature of the drying ir on the accuracy of the calculations have been evaluated. The results obtained will aid in the development of an au matic control system for textile dryers, based on the measurement of wool regain during drying by this method.

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