El efecto se llama Prandtl–Glauert y yo tenía entendido que esa forma de condensación se produce por (perdón, edito) caída súbita de la presión (y no por la alta presión como habia puesto) al momento o en velocidades supersónicas...
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Ahora encontré esto.. The Prandtl–Glauert also referred to as a vapor cone, shock collar, or shock egg, is the point at which a sudden drop in air pressure occurs, generally accepted as the cause of the visible condensation cloud that often surrounds an aircraft traveling at transonic speeds, though there remains some debate. It is an example of a mathematical singularity in aerodynamics. Understand that these Prandtl-Glauert condensation clouds can also occur at lower speeds, and are not really a visible manifestation of some kind of a sound barrier being broken.