Method for determining ultrasonic velocity of liquid contained in fuel tank that is utilized for operating vehicle, involves computing ultrasound velocity based on measured running time and calibrated distance of reference point

摘要

The method involves determining a level higher than a reference point (5) by measuring interaural time difference between the reference point and another reference point (6) at a known distance between the two reference points. Running time up to the former reference point is measured, and a distance (s1) of the former reference point is calibrated by an ultrasonic sensor (2). Ultrasound velocity is computed when a level of a liquid is below the latter reference point based on the measured running time and the calibrated distance of the former reference point.