METHOD FOR DETERMINING A STIRRER'S POSITION IN LIQUID STORAGE TANKS

摘要

The stirrer has vertical buoyancy tanks fitted to its upper part and is provided with rotors which generate horizontal and vertical propulsion. It stirs the liquid uniformly as it moves freely through a liq. storage tank, thus preventing the accumulation of sludge. The vertical buoyancy tanks stabilise the stirrer and provide a restoring force if the stirrer is upset. The stirrer is fitted with an ultrasonic wave emitter, and ultrasonic receptors are installed at several positions in the liq. tank. An ultrasonic pulse is emitted after a certain interval when the stirrer is at rest on the bottom of the tank. The position of the stirrer is computed for each pulse emission, and the average is taken to give the actual position of the stirrer.