Application Of Ultrasound In Tap-water Tank

The thesis relies on science and technology projects"ultrasonic tank research and development"in Guangdong Province, thesis experiment develops and designs a set of ultrasonic water tank with capacity of two cubic meters. Ultrasonic tank is made of stainless steel,and divided into two regions of A and B. The thickness of side and bottom is two mm and three mm, both are reinforced by stainless steel column to prevent excessive pressure from distortion. Tank lid is designed with folded structure in support of easy installation and maintenance. Tank bottom is inclined into a ten angle from the horizontal plane,drain valve is tangential with bottom plate so that the deposit inside the tank is discharged smoothly after washing. Inlet valve, supplying valve and water level sensor are installed in close to the upper and lower edges of tank. Differently cleaning valve is deviced with curtain structure, the ingenious set of these valves can achieve the best beneficial cleaning effects. ten ultrasonic transducers whose frequency is twenty hertz, power is fifty watts, are installed at the bottom of the tank and connected with the ultrasonic generator and control circuit box. When the water level sensor senses the signal that the water level is full or empty, immediately changes it into a low current signal and transmittes to the control circuit by A/D conversion. Control circuit is equivalent to a"brain"of the water tank, its working voltage is DC-five volt, the hardcore is MCU 89C51 chip, auxiliary section is composed of the relay, relay driving chip-level HD74LS244P and ultrasonic driving chip-level HD74LS04P. Every valve uses electromagnetic valve with filter, and each operating voltage is DC-nine volt, while connecting resistance of two hundred and fifty ohms. The whole control circuit is made into PCB plate, so as to achieve the best effects of operating stability, structural clarity, thorough order and dust-proof and waterproof. The work program is developed throughout embedded programming, after program initialization, area A starts water supply. when area A water supply is completed, empty sensor senses signal, immediately water supply turns to area B.Meanwhile inside area A, the cleaning valve and drain valve switch on, driving ultrasonic transducer to clean area A; when area B has finished water supply, its sensors sense signals, water supply immediately turns to area A, and meanwhile area B gets into cleanning state, such the system recycle.Using ultrasonic technique in water tank is a pure physical means without bringing out any chemical pollution on the water, and can not bring any new pollution and negative effect to water quality. it is a very safe, excellent, environmentally- friendly and modern energy-saving automatic water supply system. Also maybe it can provide reference for production and supply of purified water and drinking water.