Effect of temperature on evaporation dynamics of sheep's blood droplets and topographic analysis of induced patterns

To characterize various induced phenomena and the blood of healthy sheep using several parameters, the evaporation dynamics of 72 drops of sheep blood evaporated at several temperatures: 23, 37, 60, and 90 °C on glass hydrophilic substrates were studied. This allows the prediction of the sheep blood pattern, knowing the surface temperature and vice versa. To determine the variation in the Marangoni number between the center and the triple line, an infrared thermography method was used to measure the temperature variation along the surface of the drop. Simultaneously, a high-performance camera was used to measure the variation in the height of the drop during the evaporation using a superior algorithm software for image analysis, drop shape analyzer, under controlled conditions (Humidity = 40%, T_atm = 23 °C). The study of the evaporation dynamics and pattern formation shows the effect of temperature on the flow circulation inside the drop, resulting in the final deposit. The results showed two categories corresponding to two different evaporation phenomena induced by the thermal Marangoni effect. Furthermore, to transform the induced pattern of sheep blood evaporation into a 3D image, a topographic study was performed using a highly accurate, fast, and flexible optical 3D measurement system. The topographic parameters were subsequently extracted from these 3D images. The statistical study showed a good correlation between the topographic parameters and the surface temperature, and a significant difference between each temperature group for each parameter.