China Safety Science Journal ›› 2022, Vol. 32 ›› Issue (5): 77-83.doi: 10.16265/j.cnki.issn1003-3033.2022.05.2075

• Safety engineering technology • Previous Articles     Next Articles

Study on wake safety intervals of PA based on CFD

HE Xin1(), MA Yilong1,2   

  1. 1 College of Air Traffic Management, Civil Aviation Flight University of China, Guanghan Sichuan 618307, China
    2 School of Rail Transportation, Southwest Jiaotong University Hope College, Chengdu Sichuan China 610400, China
  • Received:2021-12-10 Revised:2022-03-20 Online:2022-08-17 Published:2022-11-28

Abstract:

In order to address the lack of accuracy in wake prediction by simple mathematical modeling method under changeable environment, firstly, basic requirements of wake safety zones in PA mode for CSPRs were studied. Secondly, wingtip vortex under influence of crosswind was numerically simulated by adopting k-epsilon model in a vortex field created at the tail of transport wing, and spatial distribution of wake vortices before pairing was obtained. Then, a calculation method of PA wake safety intervals was put forward based on CFD after analyzing PA wake safety zones. Finally, with Shanghai Hongqiao Airport as an example, numerical simulation was conducted for a case where lead aircraft and trail aircraft were B747-400 and B737-800 respectively under crosswind of 3 m/s to verify the proposed method in terms of scientificity and effectiveness. The results show that crosswind can intensify transverse displacement of wakes, and trail aircraft can follow up flight in upwind direction of lead aircraft so as to avoid influence of wakes. When flight environment is constant, lead aircraft's wingspan is the decisive factor for maximum wake safety interval of PA. It is also found that the calculation results of safety intervals based on CFD can better fit experimental measured values, thus improving calculation accuracy. Moreover, CFD-based results are far less than current wake interval standard under the condition of same paired types.

Key words: computational fluid dynamics (CFD), paired approach (PA), wake safety interval, closely spaced parallel runways(CSPRs), numerical simulation