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A nonlinear dynamic model of monorail vehicle and a finite element model of “running wheel-rail beam” system is established respectively, which is integrated into the Modefrontier platform. The total friction work and friction work deviation value are proposed as indicators for evaluating the wear and partial wear of the running wheels. Taking the total friction work and friction work deviation as the goals, the stability and curve passing performance of the monorail vehicle as constraints, and the structural parameters and dynamic parameters of the monorail vehicle as the optimization variables, an optimization model of partial wear of running wheel was established. The structural parameters and dynamic parameters of monorail vehicle are optimized through improved genetic algorithm. The analysis results show that the two indicators of the total friction work and friction work deviation value of the running wheels both decreased. Among them, the total friction work of the front right and rear right running wheel with severe partial wear was reduced by 20% and 21.2% respectively, the friction work deviation value was reduced by 19.30% and 27.2% respectively. The partial wear of the running wheel is improved significantly, and the purpose of reducing the partial wear of the running wheel is achieved.

During the cell viability detection process inside a microfluidic chip, the more uniform the distribution of medium flow rates, the higher the accuracy of detection results. In order to achieve this goal, a multichannel microfluidic chip with uniform distribution of medium flow rates has been successfully designed. The multichannel microfluidic chip is designed with cell injection channels, vascular network-shaped medium injection channels, buffer zones, and a culture chamber. The medium flow rates inside culture chambers of the multichannel microfluidic chip and the common single-channel microfluidic chip are compared by COMSOL Multiphysics software and particle velocimetry experiment. The simulation and experimental results show that the medium flow rate distribution inside the culture chamber of the multichannel microfluidic chip is more uniform and changes more smoothly. When the medium perfusion flow rate is 0.5 μL/min, the maximum flow rate difference inside the culture chamber of the single-channel microfluidic chip is more than 13 times that of the multichannel microfluidic chip. Therefore, the multichannel microfluidic chip can ensure a uniform supply of medium inside the culture chamber, which is beneficial to improve the accuracy of cell viability detection.