Common-path heterodyne laser-induced thermal acoustics for seedless laser velocimetry.
نویسندگان
چکیده
We demonstrate the use of a novel technique for the detection of heterodyne laser-induced thermal acoustic signals that allows the construction of a highly stable seedless laser velocimeter. A common-path configuration is combined with quadrature detection to provide flow direction, to greatly improve robustness to misalignment and vibration, and to give reliable velocity measurement at low-flow velocities. Comparison with Pitot tube measurements in the free stream of a wind tunnel shows root-mean-square errors of 0.67 m/s over the 0-55-m/s velocity range.
منابع مشابه
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ورودعنوان ژورنال:
- Optics letters
دوره 27 9 شماره
صفحات -
تاریخ انتشار 2002