Other Aviation Safety
Wake Vortex Warning System
This year's international air traffic is to be the largest on record. Air traffic has grown steadily with about 4 percent of growth rate on average. With the increase of aviation demand, the ability to process logistics has reached its limit. To overcome this, while ensuring the safety, a method for increasing the efficiency of airport capacity is needed. As a consequence of lift, aircraft generate a pair of long-lived counter-rotating wake vortices that bear a potential risk for following aircraft. For that reason, “Wake Vortex Warning System” is required. It predicts the motion of a wake vortex in real time with meteorological data around the airport and identifies the hazardous area to the following aircraft. The high fidelity CFD code with the data assimilation, the wake vortex prediction tool, and the aircraft control stability prediction are included in the system.
Meteorological and wake vortex raw data from measuring equipment, like lidar, converted to initial/boundary condition of CFD without any loss of accuracy. The objective of data assimilation is to obtain an initial flow condition which reproduces corresponding measurements during the unsteady flow simulation starting from this initial flow condition. To minimize the numerical dissipation, high fidelity NS-LES analysis is needed to simulate the behavior of wake vortex accurately. It needs to be investigated atmospheric turbulence related to flight of aircraft, such as clear air turbulence and wake turbulence based on measurement-integrated simulation approach. The measurement integration was performed based on the data assimilation method.
Analytic solution of wake vortex must include as much physics as possible gained from both data assimilation and numerical wake vortex research. The solution employs a well-defined vortex strength and evolution with probabilistic components to meet the variability of wake vortex behavior. Using POD method, build approximate model from decomposed CFD result to predict the wake vortex flow field qualitatively in real time. The POD is a technique for decomposing a coherent structure into a set of orthogonal spatial POD basis vector and a set of temporal coefficients.
Calculate the induced forces and moments by wake vortex in the Source-Doublet Method technique. (figure 5) The position and strength of the wake vortex are stochastically calculated using analytic or POD based prediction tool. The operating hazardous zone is determined by the controllability, and hazardous zone is reported to the air traffic control center. (figure 6)
References
[1] Dijick E. V., Copyrighted photo printed with written permission.