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Show -4- Em~loying the principle of the Tesla diode and the boundary-layer effect, the multl-~affle reverse flow seal uses the kinetic energy of air attempting to enter a flare tiP to turn that intruding air back upon itself. (This technology has also been used to develop effective Fluidic Windshields™ for flare pilots to maintain controlled flame patterns despite winds up to 250 mph.) Wind .vel~city and wind direction are less significant than the kinetic energy of the wind Itself. The greater the turbulence and downward pressure of the wind, the greater the effectiveness of the patented kinetic seal. The effectiveness of this unique, maintenance-free seal is not influenced by wide variations in waste gas flow. There is no need for any troublesome refractory lining inside a Fluidic Flare tip. Other advantages include: No bottom-mounted molecular seal with significant structural and windloads on elevated stacks; and no need for frequent maintenance and replacement of refractory-lined flare burner tips. The working life of a Fluidic Flare tip is typically five times longer than a troublesome refractorylined flare tip. (Many Fluidic Flares in continuous service onshore and offshore since the 1970s have never been replaced.) Safety is a very important advantage of the Fluidic Flare tip. In addition to preventing air intrusion, the compact, lightweight kinetic seal, proven in more than 2700 worldwide installations, eliminates all serious safety problems involved in cutting out corroded sections of molecular seals, removing broken refractory, then welding on metal patches, high above a plant where volatile fumes may be present. Since the late 1970s, the Fluidic Seal has been positioned at the very top of the refractory-free flare tip. Patents cover the unique design configuration and the positioning of this multi-cone seal. (U.S. patents 3,730,670 & 4,092,908. Also protected by foreign patents. Other patents pending.) Flame Stability in Crosswinds A flare is only as good as its ability to maintain a stable flame, despite wind and weather conditions. An effective flame retainer/flame holder on the top of a flare burner is the key element in maintaining a stable flame. Without a flame retainer, the flame will lift off; and it may be snuffed out by crosswinds. The maximum exit velocity for many flares is approximately Mach 0.2, or 220 ftls (67 m/s) for natural gas. With other types of flame holders such as a bluff body, the exit velocity can increase to Mach 0.5. Unfortunately, most flame retention designs are not very effective. |