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Aircraft wake vortex is a pair of strong counter-rotating vortices and has attracted considerable attention in various fields including aviation safety and atmospheric physics. The characteristics and detection of wake vortex act as the basis for both behavior prediction as well as hazard assessment. This paper provides a short survey of the charac...
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... wake has attracted much attention in aviation safety field. As is known, aircraft wake is a strong irregular airflow. It could be very dangerous in aviation since it may cause a following aircraft to roll out of control (see Fig. 2). According to the statistics of National Transportation Safety Board, abut 1/3 of US aviation accidents were related to wake vortices between 1993 and 2000 [2] ; For example, an American Airlines Airbus A300 crashed shortly after taking-off at J. Journal of Radars Vol. ...
Citations
... At present, the main sensors for wake vortex detection are lidar and radar, and the performances of these two sensors can be found in the researches by Li and Wang [2] Li et al. [3], Oude et al. [4] and Barbaresco et al. [5]. Under clear air condition (sunny day), the echo signals are mainly caused by the particles involved in the wake vortex, and the effective sensor is lidar. ...
Aircraft wake is a pair of strong counter‐rotating vortices generated behind a flying aircraft, which might be dangerous to the following aircrafts. The real‐time and precise locating of aircraft wake vortex‐core positions is essential in the aviation safety field, especially in airport traffic management. This study proposes a two‐step vortex‐core locating method which uses the Gabor filter to make a preliminary locating and the velocity range distribution to make a fine locating consequently. The combination of Gabor filter and Doppler velocity distribution can improve the method's adaptability to complex background wind field and mitigate the impact of noise. Numerical examples and field detection campaigns from Changsha Huanghua International Airport and Hong Kong International Airport have well verified the good performance of the method, in terms of both accuracy and real time.
... The existing monitoring sensors for wake vortex include Radar and Lidar, and they are applicable for different weather conditions due to their different scattering mechanisms. Under clear air condition, the scattering is mainly determined by the aerosols involved in the wake vortex, and the widely-used wake vortex sensor is Lidar [1][2][3][4][5]. But under rainy/foggy/snowy conditions, Lidar doesn't work well due to the heavy attenuation and the proposed sensor is radar [6][7][8][9][10][11][12][13][14]. ...
Aircraft wake is a pair of strong counter-rotating vortices generated behind a flying aircraft. It might be very hazardous to a following aircraft and the real-time detection of it is of great interest in aviation safety field. Vortex-core positions and velocity circulations, which respectively represent the location and strength of a wake, are two characteristic parameters that have attracted the main attention in wake vortex detection. This paper introduces a new algorithm, the Path Integration (PI) method, to retrieve the characteristic parameters of wake vortex. The method uses Doppler velocity distribution to locate the vortex-core positions, and the integration of Doppler velocity along a LOS (line-of-sight) is derived as a linear expression about the circulations. From this expression, the circulations can be solved with the least square method. Moreover, an vortex-core position adjusting method is proposed to compensate the compressing and expanding effects of wake vortex caused by the scanning of Lidar beam. Basically, the use of Doppler velocity integration can improve the method’s adaptability in turbulence environment and mitigate the impact of noise. Numerical examples and field detection data from Hong Kong international airport and Tsingtao Liuting airport have well verified the good performance of the method, in terms of both accuracy and efficiency.
... To avoid such accidents, ICAO (International Civil Aviation Organization) released a series of regulations for the minimal temporal-and spatial-separations between flights in the 1970s. These regulations can ensure the safety of flights most of the time, but they are conservative and believed to have limited the capacity of airports to a certain degree [2,3]. With the rapid increase of air traffic, the detection and parameter-retrieval of wake vortices are greatly demanded by ATM (air traffic management) to adjust the departure and landing of flights in real-time for higher capacity. ...
A wake vortex is a form of irregular airflow generated by a flying aircraft, which can cause a severe hazard for aviation. To quantify the hazard of a wake after fully roll-up and before rebound, this paper proposes an algorithm to retrieve its characteristic parameters (circulations, vortex-core positions, and vortex-core radii) with a scanning Doppler Lidar. In the algorithm, a governing equation related to the Doppler velocities and characteristic parameters is established based on the aerosols’ weak inertia, from which the target parameters are solved with an optimization method. During the process, the distortion of Doppler velocity caused by the scanning of the Lidar beam is adjusted by the Doppler acceleration to achieve better estimations of the target characteristic parameters. Good performance of the algorithm has been verified by simulation and field detection data.
... In the area of aviation safety, the circulation is a crucial parameter for assessing hazards of wake vortices. After decades of research, various retrieval methods for vortex circulation have been proposed, and different sensors (Radar and LiDAR) are also proposed considering different weather conditions (clear air condition and precipitation condition) [14]. ...
