Advances in Heat Transfer Engineering

ISBN Print: 9986-49278-5

INVESTIGATION OF THE AIR VELOCITY NATIONAL STANDARD

DOI: 10.1615/BHT4.900
pages 785-792

Abstract

The Lithuanian national standard is intended to reproduce air velocity units in the range from 0.2 up to 60 meters per second with uncertainty less than ±(7.0−1.0)% and transfer it to all kinds of the air velocity working standards. National air velocity standard is based on the 3 Pitot tubes, 3 convergent nozzles and ultrasonic anemometer. The Pitot tubes reproduce local air velocity starting from 3.0 m/s, convergent nozzles − mean cross-section air velocity in the range of 0.2−30 m/s. The last results of Pitot tubes, convergent nozzles and ultrasonic anemometer calibration are presented. The airflow stability and air velocity distribution in the different cross sections of the standard test parts were measured.