Abstract

Landing gear models are examined at 1/12th scale to determine the main noise generating features on simplified, four-wheel bogies aligned with the flow. Previous experiments have indicated that changes to wheel shape and model layout can have substantial effects on model noise. In this paper we explain these changes in noise level and present surface oil visualization of the mean flow for different wheel shapes. Acoustic measurements describe the noise generated by major components of the landing gear model and identify sources at the wheel edges, rear axle and oleo/beam junction. The most important noise sources were the result of wake-body interactions and we present changes to the wheel shape, layout of the landing gear and local fairings as successful methods of noise reduction. Results suggest that modest changes in design could yield a much more stable flow over the landing gear, substantially reducing noise generated by all components.