Fluid Similarity Criterions in Aircraft Landing Gear

¹ School of Mechnical Engineering, Tongji University, NO:4800 Caoan Highway, Shanghai, China.
² The Institute of Fishery Machinery and Equipment, NO:63 Chifeng Road, Shanghai, China.

Abstract

Facing the design difficulty and risk of aircraft landing gear, the fluid similarity theory and model experiments are used to predict large prototype’s property, which provide guidance for hydraulic designation and selection to reduce risk. Firstly, the matrix method is used to establish the fluid similarity relationship between the prototype and the model’s luffing mechanism, and the above conclusions are used to design the prototype’s hydraulic system. Secondly, the luffing mechanism’s dynamical model with accumulator was established, the initial motion condition was set, and the pressure’s similarity ratio is obtained by simulation method. Finally, the dynamic model and similarity ratio about time, velocity and pressure are verified by the prototype and model’s experimental data.