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In this paper, a two-way fluid-structure coupling model is developed to simulate and analyze the hemodynamic process based on dynamic coronary angiography, and examine the influence of different hemodynamic parameters on coronary arteries in typical coronary stenosis lesions. Using the measured FFR pressure data of a patient, the pressure-time function curve is fitted to ensure the accuracy of the boundary conditions. The average error of the simulation pressure results compared to the test data is 6.74%. In addition, the results related to blood flow, pressure contour and wall shear stress contour in a typical cardiac cycle are obtained by simulation analysis. These results are found to be in good agreement with the laws of the real cardiac cycle, which verifies the rationality of the simulation. In conclusion, based on the modeling and hemodynamic simulation analysis process of dynamic coronary angiography, this paper proposes a method to assist the analysis and evaluation of coronary hemodynamic and functional parameters, which has certain practical significance.

Aiming at the excessive vibration issue of a crane frame, the vibration damping performance of both engine and transmission mounts was evaluated and optimized with experiment and simulation. Firstly, test detection and vibration acceleration spectrum analysis of 20 points were conducted to investigate the cause of excessive frame vibration through modal analysis. Calibration of the simulation process was completed based on the test data. Secondly the vibration damping performance of both engine and transmission mounts were optimized with the simulation process. Finally, the proposed optimization scheme was verified through testing. The results show that the vibration amplification of the frame is caused by the resonance between the mount natural frequency and the excitation frequency of the transmission near 450Hz and 690Hz. Through optimization design of the transmission mounts, the resonance issue of the transmission is effectively improved and vibration transmission rate meets requirement of less than 70%.

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