Earticle

In this study, infrared thermometry techniques were used to conduct surface wetting performance tests (wicking tests) on micropillar structures with good fluid supply capabilities to enhance the critical heat flux. Wicking tests were conducted based on various micropillar shapes (i.e., diameter and spacing) to investigate the surface wetting performance near the boiling point of the fluid(~100°C). The surface temperature was increased from 20°C to 95°C, to examine the wicking performance The shape of the micropillars were quantified by the roughness and the effect of the roughness and temperature on the wicking performance was analyzed. As a result, we confirmed that the roughness of the micropillars increases the capillary pressure, improving the wicking performance. The sample D04 G10 with the highest roughness coefficient at room temperature (r=2.51) exhibited the highest wicking coefficient, showing a 170% improvement in wicking performance compared to D04G20 with the smallest roughness coefficient at room temperature(r=1.51). Additionally, the D04 G10 sample (r=2.51) recorded a 50% improvement in the wicking coefficient at the highest temperature(95°C) compared to room temperature(20°C). The wicking coefficient data will be utilized as a database for developing a new correlation for critical heat flux.

Gnotobiotic piglets (n = 10) were hand-reared in conventional germ-free facilities. Piglet body temperatures were measured with rectal and non-contact infrared thermometry (NIFT) on the lower eyelid, auricular center and margin, parietal regions, axilla, central abdomen and dorsum, and the perianal region. Body temperature measurements at central abdomen, cranial dorsum, and perianal regions had NIFT values which had a significant linear relationship (p<0.0001) with rectal thermometry. The predicted equations of between-subject formulas were calculated as follows: rectal temperature, 28.07489+0.30372${\times}$central abdominal surface temperature; rectal temperature, 34.02799+0.15197${\times}$central dorsum surface temperature; and rectal temperature, 33.87937+0.15676${\times}$perianal temperature. These results suggested that NIFT could serve as a valid alternative to rectal thermometry in a portable germ-free facility without disturbing experimental animals. The development of a NIFT body temperature evaluation that does not require animal restraint is clinically advantageous, particularly in gnotobiotic piglets, and would be significantly less stressful for experimental procedures in germ-free facilities.