Extended Data Fig. 7: Thermal characteristics of STA surfaces.
From: Inhibiting the Leidenfrost effect above 1,000 °C for sustained thermal cooling
a. Temperature map of a STA surface brought to 1000 °C. Temperature is measured with an infrared camera (FLIR T1050sc) operating at 30 Hz, with an emissivity setting at 0.95. At t = 0 ms, temperature is nearly uniform. The tops of the steel pillars are slightly cooler (by 15 °C) than the membrane, which might be due to the embedded position of the membrane. 198 ms after a drop impact, we observe a strong temperature difference (about 290 °C) between pillars and membrane. b. Evaporation time τ of a water drop of 17 µL deposited on STA at T = 1000 °C, as a function of the pillar density ϕ = a2/(a+b)2. c. Mean heat flux q as a function of ϕ. q is deduced from the time τ and from the measured evaporating solid/liquid area. An optimum of performance is found around ϕ = 0.25. Data are mean ± s.d. from at least five independent measurements.
