Geçiş-zamanı esaslı bir ultrasonik akış ölçerin tasarımı ve uygulaması

Bu çalışmada, kalori-metrik akış ölçerlerde kullanımı giderek yaygınlaşan ultrasound ile adlandırılan yüksek frekanslı ses dalgaları teknolojisi, alışılmış akış ölçerler üzerinde denenmiştir. Akış ölçümü için geçiş-zamanı yöntemi esas alınmıştır. Çalışmada yüksek doğrulukta zaman ölçümü için sayısal zaman çevirici yongası ve PIC18F4520 mikro-denetleyici birlikte kullanılmıştır. Sistemde ayrıca, 4 MHz frekanslı iki ses-ötesi transdüser kullanılmıştır. Basit yapısı nedeniyle çapraz biçim tüp tercih edilmiştir. Çalışmada söz konusu akış ölçerin maruz kaldığı etkilere ve bu etkilerden dolayı oluşan ölçüm doğruluğu hatalarının deneysel sonuçlarına yer verilmiştir.

Design and implementation of a transit time based ultrasonic flow meter

In this study, the high frequency sound wave technology which is known as ultrasound and is becoming widely used in calorie-metric flow meters was experimented on the ordinary flow meters. The transit-time method has been considered as the basis of the flow measure. Digital time converter and the PIC18F4520 as a microcontroller were used to achieve a high accuracy time measurement in this study. In addition, two 4 MHz ultrasound transducers were used in the system. A diagonal type tube was used due to its simple construction. The effects that the flow meter is exposed to and the experimental results accuracy errors obtained from these effects are studied in this paper.

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