In order to test the Simulink models, this paper focused on the model-based testing for Simulink based on mutation testing. Considering the situation that the present model-based test adequacy criteria are imperfect, we propose a mutation testing process for Simulink models. Based on studying the application of mutation testing technique to Simulink models, some improvements on mutation operators for Simulink models are presented. The experimentation results verified the effectiveness and correctness.

Particle impact damping (PID) is a technique of achieving high structural damping with small metallic particles embedded within a cavity that is attached to vibrating structure. This is a highly non-linear damping mechanism in which energy dissipation is primarily related to friction and impact phenomena. In this work a simple yet detailed analytical model is presented to study PID in two dimensions under transient vibrations. Normal as well as oblique impacts are considered. The effect of cavity size and acceleration amplitude on PID is studied and the results are supported by experiments. Fairly good agreement is found between the theory and the experiment.

The design method research of position schemes for particle dampers applied to a flywheel under sinusoidal excitation has been investigated, in which discrete element method (DEM) and finite element analysis are used to study the relationship between the damping capacity of dampers filled with different metal particles and the dimensionless acceleration amplitude, and the specific parameter of radial position is introduced to discuss the influence on particle damping caused by different dampers attachment locations. A series of corresponding experimental investigation are conducted subsequently and the results indicate an auxiliary position scheme if the acceleration response of optimum location exceeds the threshold. It can be concluded that with the help of the specific parameter of radial position, the experiment results can be well explained, in addition, the design efficiency and accuracy will be raised, especially in the condition that the particles mass is strictly limited.

A fast numerical method based on aeroelastic eigenvalue analysis is applied to study the effects of mistuning on the aeroelastic stability of turbomachinery blades in which the structural coupling is included by a simplified method and an influence coefficient method is employed to deal with the unsteady aerodynamic effects. Results show that there exists an optimal mistuning amount at which the system has the best aeroelastic stability. Structural coupling almost has no effects on aeroelastic stability of a tuned system. But the benefit of alternate frequency mistuning to aeroelastic stability is inhibited drastically when structural coupling is introduced into the bladed disk system.

The stress concentration phenomenon around holes in rotated components is discussed. Firstly, finite element analysis of a simplified model of turbine disc flange is carried out, and then a method is developed by designing an intended-cut notch on the model to reduce the stress around the pin hole. Furthermore, two characteristic parameters which determine the configuration of the notch, namely notch depth and arc length parameter, are investigated by changing the notch dimensions. The results show that this method can reduce the stress around the hole significantly, notch depth and arc length have an important impact on the stress concentration factor (SCF), the SCF decreases with the increase of notch depth, and increasing the arc length within a critical scope results in the decrease of the SCF.