Development of an Ultrasonic Airflow Measurement Device for Ducted Air

Sensors

Andrew B. Raine²  Nauman Aslam¹  Christopher P. Underwood²  Sean Danaher² 

[1] Faculty of Engineering and Environment, Northumbria University, Newcastle upon Tyne NE18ST, UK;

关键词: acoustics;    airflow rate;    ultrasonic flowmeter;    ventilation air flow measurement;    differential transit time method;    time difference method;    ultrasonic transducer damping;    ultrasonic receiver amplifier;   

DOI  :  10.3390/s150510705

来源: mdpi

【 摘 要 】

In this study, an in-duct ultrasonic airflow measurement device has been designed, developed and tested. The airflow measurement results for a small range of airflow velocities and temperatures show that the accuracy was better than 3.5% root mean square (RMS) when it was tested within a round or square duct compared to the in-line Venturi tube airflow meter used for reference. This proof of concept device has provided evidence that with further development it could be a low-cost alternative to pressure differential devices such as the orifice plate airflow meter for monitoring energy efficiency performance and reliability of ventilation systems. The design uses a number of techniques and design choices to provide solutions to lower the implementation cost of the device compared to traditional airflow meters. The design choices that were found to work well are the single sided transducer arrangement for a “V” shaped reflective path and the use of square wave transmitter pulses ending with the necessary 180° phase changed pulse train to suppress transducer ringing. The device is also designed so that it does not have to rely on high-speed analogue to digital converters (ADC) and intensive digital signal processing, so could be implemented using voltage comparators and low-cost microcontrollers.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.