| 摘要 |
PROBLEM TO BE SOLVED: To enable the highly accurate determination of volatility by measuring the velocity of ultrasonic waves passing through gasoline in which alcohol, etc., is added and compensating deviations from a reference temperature. SOLUTION: Ultrasonic waves 4 transmitted from a transducer 1 propagate through gasoline to be measured before reaching a reflecting plain and are again received by the transducer 1. The sound waves of the gasoline to be measured are obtained by dividing propagated distance by propagation delay time. In addition, ultrasonic waves 4 are serially and simultaneously transmitted from the transducer 1 through a substance whose periphery is sealed, and the value of sound velocity is obtained in the same way. Temperatures in both cases are the same. It is possible to send and receive ultrasonic waves 4 through a substance 2 whose sound velocity-temperature property is known by providing a structure such as (b), and cost reduction becomes possible without the need for a temperature sensor such as a thermocouple. In addition, by measuring the reflection intensity of the known substance 2 and also the reflection intensity in the gasoline, it is possible to compensate deviations by measurement temperatures with ease and to obtain accurate volatility. |
