INFRARED-ABSORPTION STUDIES OF FABRICS

A technique is discussed in this paper for evaluating the performance of IR emitters in heating and drying fabrics. The efficiency of IR hea ting depends on both the fabric spectral absorption characteristics an d the spectral emission of the infrared source. An FTIR spectrometer w ith an integrating sphere:is used to measure the infrared absorptiviti es of fabrics over the range of wavelengths from 0.7 to 25 microns (th e range of operation of commercial infrared emitters). Spectral absorp tivities are used with the normalized emission characteristics of blac kbody emitters to calculate average fabric absorptivities for blackbod y emitter temperatures ranging from 500 to 3000 K. Overall radiant eff iciencies for heating fabrics with blackbody emitters are calculated b y multiplying average fabric absorptivities by the radiant efficiencie s of emitters in converting input power to IR radiant output power. Th e effects of fabric characteristics on spectral absorptivities, averag e absorptivities, and overall radiant efficiencies are studied. Parame ters include fiber type, fabric weight, moisture regain, fabric constr uction, and dyeing. The technique used in this investigation is useful in matching IR emitters with applications for the textile industry.