This article presents groundbreaking research on wool felt for use in hospital accessories. The results of mechanical, scanning electron microscopy (SEM), chemical, flammability, and microbiological tests are presented, as well as research on the acceptability of three wool felt hospital accessories (i.e. sheet cover, pillowcase cover, and insole). An innovative approach was utilized to compare the mechanical properties of unwashed and washed wool felt samples by three different washing machines, with textiles commonly used in hospital (i.e. nonwoven of polyester felt, woven of 100% cotton, and woven of a blend of 67% cotton and 33% polyester). The mechanical tests showed that the wool felt had tensile resistance similar to that of polyester felt, superior elongation to the 100% cotton and the blend, inferior tearing stress, lower resistance to slippage, and good pilling resistance. After washing, the wool felt washed with the extractor washer and dry washer increased their tensile strength 33% and 19%; the tear strength did not change; the slippage decreased; and the samples washed with the dry washer showed 14% less pilling than those not washed. The SEM tests showed differences in appearance of the fibers after the washing processes. Chemical tests revealed that 0.11% of lanolin was retained in the wool felt after washing the samples with the dry process. The flammability tests showed the dependence of carbonization length with the wool felt washing process. The volunteers showed a good acceptance of the wool felt accessories emphasizing the feeling of freshness, release of pain, and reduction in sweating and unpleasant odors. Microbiological tests showed growth in the insoles of the bacterium Staphylococcus aureus and the fungus Candida albicans, commonly found in the hospital environment.

No abstract

This work presents a simplified model for encapsulated ice tanks. The model considers the tank as a heat exchanger and uses the effectiveness approach to simulate the ice formation and melting periods. The main part of this work consisted of the development of empirical correlations for the thermal transmittance UA and tuning it based on experimental tests in a test facility. The input variables are the inlet temperature and flow rate of the secondary fluid, while the output variables are the outlet temperature, the heat transfer rates, and the ice tank inventory. It was verified that the heat transfer area for freezing and melting is not constant. Additionally, the model was validated for other tank capacities using manufacturer data. It was observed that a similarity exists, and general correlations of UA for both periods are expressed in terms of three dimensionless variables-the "weight ice fraction," the "energy ratio," and the "tank volume ratio."

No abstract