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On the basis of the principal components analysis-particle swarm optimization-least squares support vector machine (PCA-PSO-LSSVM) algorithm, a fault diagnosis system is proposed for the compressor system. The relationship between the working principle of a compressor system, the fault phenomenon, and the root cause is analyzed. A fault diagnosis model is established based on the LSSVM optimized using PSO, the compressor fault diagnosis test experimental platform is used to obtain the fault signal of various fault occurrence states, and the PCA algorithm is employed to extract the characteristic data in the fault signal as input to the fault diagnosis model. The back-propagation neural network, the LSSVM algorithm, and the PSO-LSSVM algorithm are analyzed and compared with the proposed fault diagnosis model. Results show that the PCA-PSO-LSSVM fault diagnosis model has a maximum fault recognition efficiency that is 10.4% higher than the other three models, the test sample classification time is reduced by 0.025 s, the PCA algorithm can effectively reduce the input dimension, and the PSO-LSSVM fault diagnosis model based on the PCA algorithm for extracting features has a high recognition rate and accuracy. Therefore, the proposed fault diagnosis system can effectively identify the compressor fault and improve the efficiency of the compressor.

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Particle fracture can influence material failure and removal mechanisms in high velocity impact progress. In this paper, a coupled finite element method-smooth particle hydrodynamics numerical model of a single irregularly shaped particle erode metal surface was established to investigate the particle fracture and metal surface erosion. The Johnson–Cook model and Johnson–Holmquist-II model were introduced to describe the deformation of ductile materials and the fracture of brittle materials, respectively. Subsequently, the erosion process of a single irregularly shaped particle impacting different material properties of metal was studied. The results showed the following: (1) The JH-2 constitutive model can simulate the fracture of brittle particles accurately, and the results between simulations and experiments were in reasonable agreement. (2) The extent of particle fracture was lower on softer substrates than on the harder ones. (3) The orientation angle was a key factor affecting secondary impacts of brittle particles. (4) The rigid particle made more damage on the substrate than the brittle one under the same condition.

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