The Faraday instability forms when a fluid interface is vibrated. This high-speed video shows the differences in the shapes formed by a vibrated fluid interface when the two fluids are miscible–capable of mixing–and when they are immiscible–like oil and water. Note how the miscible interface breaks down quickly into turbulence, but the immiscible interface maintains a complex shape.
Tag: mixing
Wind Turbines and Weather
A new study reports that wind turbine farms may be changing local surface temperatures, resulting in warmer temperatures at night and cooler temperatures during the day. The result is neither surprising nor new; the motion of the propellers increases the turbulence downstream of the turbines. Turbulent flow mixes much better than laminar flow, so air from above the ground is getting mixed into surface air in the wakes. At night, the air next to the ground cools more quickly than air higher up, so the mixing of higher, warmer air results in localized warmer air on the ground. Orange farmers use this effect when they put out fans at night to keep their crops from freezing. #
Phytoplankton in Bloom
Phytoplankton blooms, aside from giving us gorgeous eddies of blue and green, can reveal how ocean currents are mixing. Blooms typically occur where nutrients are being washed together. #
