Xia Yimin

Optimal Design Method of Magnitude of Interference for Disc Cutter Geology Adaptability

In the rock fragmentation process, the disc cutter, tunnel boring machine’s main rock-breaking tool, often lose rock-breaking capability because of the improper selection of the magnitude of interference between the disc cutter ring and the body. The three-dimensional software SOLIDWORKS and the finite element software ANSYS is used to build mathematical model. And the aim was to optimize the magnitude design of interference between the disc cutter ring and its body, when the disc cutter cutting granite stratum. We analyzed the stress-strain of disc cutter ring and transmission torque on contact surface, finally obtained the optimal magnitude of interference (0.05mm). It could be verified with site operation. Therefore, in order to adapt the different geological condition, the finite element method provided theoretical basis for determining the optimal magnitude of interference between the disc cutter ring and the body.

Chaos Analysis of Reverberation from Short Distance Acoustic Detection in Deep-Sea Mining Environment

In order to research reverberations whether are chaotic in deep-sea mining environment, this paper reviews nonlinear dynamics relevant theories, the characteristic of selecting linear region is proposed for small data sets algorithm. Microtopography was detected in the simulative environment of deep-sea mining, Three kinds of typical reverberations were acquired in different working conditions. Phase space reconstruction parameters of the reverberations are estimated. The largest Lyapunov exponents of the reverberations also are calculated in phase space, the largest Laypunov exponents are greater than 0 and less than 0.1. In contrast to white Gaussian noise, this paper demonstrates the chaotic dynamics of reverberations generated from microtopography detection in the deep-sea mining complex environment. The results provide a new approach of nonlinear dynamics to model and process reverberation generated from short distance and high frequency acoustic detection in deep-sea mining complex environment.