Abstract
In this study, a flow meter using multipath ultrasonic shift is proposed for the internal airflow. The experiment was conducted between 2.0m/s and 9.0m/s using a pipe with diameter of 160 mm. The frequency of ultrasonic was 40kHz and ultrasonic was sent as burst signal of 20 cycles at interval of 50ms by function generator. Flow rate was calculated as the average of each measurement path. The resultant error of straight pipe and 2 types bended pipe measurement were lower than 4%, 16% and 25% respectively against reference flow rate measured by orifis flow meter.
