Numerical investigation of the flow around a realistic nose landing gear
(English)Manuscript (preprint) (Other academic)
Detached-eddy simulations of the flow around a realistic two- wheeled nose landing gear are conducted, at a Reynolds number corresponding to the final approach phase for a regional aircraft. The main focus is on the flow and associated sound fields in the inter-wheel region and in the wake of the landing gear. Three unstructured grids are designed to evaluate the sensitivity of the solution to grid resolution. The three flow solutions agree well, although the turbulent wake requires a fine mesh. In addition, comparisons with available experimental data on two other nose landing gear models, the PDCC and LAGOON gears, yield a good qualitative agreement. The wake of the landing gear assembly is strongly three-dimensional and exhibits a complex behaviour. The effect of the torque links and wheel axle on the flow dynamics and sound sources were examined via simulations on different configurations. The presence of the torque links and the wheel axle, often simplified or omitted in numerical landing gear studies, were found to strongly modify the flow in the inter-wheel region and in the wheel wakes. The noise was propagated to the far-field using the convective form of the FWH integral. The far- field noise at sideline receivers agrees well with wind-tunnel measurements and the overhead noise sources in the inter-wheel region are identified by considering the integrand of the FWH analogy.
landing gear; flow; numerical; detached-eddy simulation; acoustic analogy; noise prediction
Fluid Mechanics and Acoustics
IdentifiersURN: urn:nbn:se:kth:diva-163049OAI: oai:DiVA.org:kth-163049DiVA: diva2:798496
QS 20152015-03-262015-03-262016-02-14Bibliographically approved