Papers by Author: Hong Nie

Abstract: Based on the piezoelectric effect and magnetorheological technology, a parameter adaptive shock absorber was designed. Considering the practical working conditions of landing gear, mathematical model of the parameter adaptive shock absorber was built. Then on the basis of LMS Imagine.Lab AMESim software, the whole combined simulation model of self-adaptive control system was constructed and the drop dynamic simulation was conducted. Results showed that compared with passive control system, parameter adaptive shock absorber reduced the peak of axial force by 10.5% and increased the absorber efficiency by 5.6%.

Abstract: This paper builds dynamical models and hydraulic system models of retraction/lowering of some regional aircraft nose landing gear respectively based on the software LMS VL motion and AMESim. The simulation analysis result was proved to be credible by checking with that of ground test. The peak oil return pressure with the critical damping force can be obtained by analyzing the hydraulic damping characteristic of actuator cylinder during landing gear emergency lowering based on methods of estimation and co-simulation. The results indicate that the damping characteristic of actuator cylinder plays an important role in emergency lowering. Only when the damping force breaks through the critical value, can the landing gear succeed in emergency lowering and being locked. However, the little damping force will result in great impact load while lowering. Thus, damping force should be changed only when emergency lowering.

Abstract: Simulation analysis and experiment research are performed on the aeroacoustic noise of a landing gear component in this paper. Detached Eddy Simulation (DES) is used to produce the flow field of the model. The Ffowcs-Williams/Hawkings (FW-H) equation is used to calculate the acoustic field. The sound field radiated from the model is measured in the acoustic wind tunnel. A comparison shows that the simulation results agree well with the experiment results under the acoustic far field condition. The results show that the noise radiated from the model is broadband noise. The directivity of the noise source is like a type of dipole. The wheel is the largest contributor and the strut is the least contributor to the landing gear noise. The results can provide some reference for low noise landing gear design.

Abstract: Simulation analysis and experiment research are performed on the aeroacoustic noise of a landing gear component in this paper. Detached Eddy Simulation (DES) is used to produce the flow field of the model. The Ffowcs-Williams/Hawkings (FW-H) equation is used to calculate the acoustic field. The sound field radiated from the model is measured in the acoustic wind tunnel. A comparison shows that the simulation results agree well with the experiment results under the acoustic far field condition. The results show that the noise radiated from the model is broadband noise. The directivity of the noise source is like a type of dipole. The location between shock absorber and strut, shock absorber and bogie can induce the interaction noise which is presented by two energy peaks in the spectra. The shock absorber and the bogie is the main contributor while the strut is the least contributor to the total noise.