اصول كاركرد دبي سنج هاي فراصوتي براي اندازه گيري جريان داخل لوله هاي تحت فشار و بحث در مورد و دقت آن ها

Ultrasonic Flowmeters (Time-Transition) for Measuring Flow in Pressure Pipes and Evaluation of Accuracy

Technical advances in ultrasonic can significantly improve flow measurement in the continuous process industries. This technique exists for both liquid and gas flows, it also exists for wide range of pressure pipes (Full-Pipe) and channels with different sizes. Ultrasonic flowmeter can be installed on the pipe wall without the need of cutting the pipe or interrupting the flow. The manufactures claimed the accuracy is between (1 to 3)% of actual flow rate. This is a typical accuracy. However some of them improved this ultrasonic technology with five beam transducers. The test results show an accuracy range (0.15-0.2)% of actual flow. This accuracy is very important for oil industries and chemical factories. In this paper the principle of sound waves and measuring by ultrasound were introduced and transient time flowmeter calculation were determined. Finally the clamp-on ultrasonic flowmeter manufactured by a private company in Iran were tested and the results compared to those obtained from the others.