| 摘要 |
<p>A strut or boom mounted probe (10) having separate pressure sensing ports or sets of ports (25, 35, 36) axially spaced at three locations on the probe. The ports are normally located on the probe so that at 0o angle of attack, the pressure difference is zero between a set of opposite ports (35, 36) at the most rear location. As the angle of attack varies from zero angle, the pressure difference at the aft measuring ports (35, 36) increases, in a positive sense with increasing angle of attack (alpha), and, in a negative sense with increasing opposite (negative) alpha angle. Pressure difference between the rear ports is also proportional to the impact pressure, q¿c?, where qc = pitot pressure minus static presure = pt - p. The sensor (10) normally has a pitot pressure opening (22) in its forward extremity and static ports (25) located along the forward cylindrical barrel section of the unit. The pressure difference at the rear ports (35, 36) is divided by the pressure difference of the forward ports (22, 25). A unique ratio of pressure is developed which is a function of angle of attack or flow direction and pitot pressure and this alternate ratio may be utilized using pitot and alpha (angle of attack) pressure only. The sensor is particularly useful at high angles of attack and provides readings at angles of attack in the range of ?+ 50o¿. Angles of side slip (beta) and other flow angles in an established measuring plane may be sensed as well.</p> |
