Constant Temperature Drying Rate Tester: Real-Time Water Evaporation Measurement of Fabrics

A prototype of constant temperature drying rate (DRCT) tester (CTDRT) was built to evaluate the DRCT of fabrics. The sample platform is kept at constant temperature and was placed on the balance. The platform temperature is adjustable to simulate different skin temperatures. A heater was placed underneath the sample platform, but it did not have any contact with the sample platform. This novel noncontact heating system enables real-time measurement of water evaporation in the sample throughout the whole experiment. In addition to DRCT, comprehensive information such as water absorption, water spreading, and other fabric drying features can be obtained from CTDRT. In addition, negative pressure gradient system of CTDRT can help to maintain constant atmospheric conditions at negligible wind speed, thereby enhancing the stability and sensitivity of measurement. The DRCT, a key parameter of CTDRT, of 28 fabrics investigated is between 0.36 and 2.56 mL/h at the skin temperature of 37 degrees C. The validity and repeatability of CTDRT were also confirmed with statistical evidence. The testing duration for CTDRT ranges from 15 to 40 min, which is similar to those of other drying methods where heat is applied, but is much faster than the conventional nonheating methods.