| 摘要 |
<p>The probe has multiple transmitters (E1-E4) distributed around a receiver (R) i.e. resonant receiver, that is sensitive to different sound waves, where each transmitter is able to emit a sound wave. A travel time measurement unit is arranged between each transmitter and the receiver. The transmitters are located at equal distance from the receiver with a step angle of 90 degree around the receiver. A determination unit determines an incidence angle (alpha) of an air flow with respect to an axis passing by the first and third transmitters.</p> |
