摘要：A design of different microtextures on the surface of the crankpin bearing(CB)is proposed to ameliorate the lubrication and friction performance(LFP)of *** the basis of the CB s hydrodynamic lubrication model,the bearing surface of CB using different microtextures,such as wedge-shaped textures(WSTs),square textures(STs),circular textures(CTs),and combined square-circular textures(CSCTs),is simulated and assessed under various external loads of the CB at an engine speed of 2000 r/*** pressure of the oil film,the frictional force,the force of the solid asperity contact,and the friction coefficient of the CB are used as objective *** indicate that the bearing surface designed by the STs remarkably improves the CB s LFP in comparison with other structures of WSTs,CTs,and ***,the average values of the frictional force,solid asperity contact,and friction coefficient of the CB using the STs are greatly reduced by 28.5%,14.5%,and 33.2%and by 34.4%,26.3%,and 43.6%in comparison with the optimized CB dimensions and CTs,***,the application of the STs on the CB surfaces can enhance the LFP of engines.

摘要：Three design modes of seat suspension,i.e.,negative stiffness elements(NSEs),damping elements(DEs),and negative stiffness-damping elements(NSDEs),are proposed to evaluate the ride performance of a *** on a dynamic model of a seat suspension and indexes of the root mean square deformation and acceleration of the seat suspension(x RMS)and driver s seat(a RMS),the influence of the design parameters of the NSEs,DEs,and NSDEs on the driver s ride comfort is evaluated.A genetic algorithm is then applied to optimize the parameters of the NSEs,DEs,and *** study results indicate that the design parameters of the NSEs and NSDEs remarkably influence x RMS and a RMS,whereas those of the DEs insignificantly influence x RMS and a *** on the optimal results of the NSEs,DEs,and NSDEs,the damping force of the DEs is 98.3%lower than the restoring force of the ***,the DEs are ineffective in decreasing x RMS and a ***,the NSEs combined with the damping coefficient of the seat suspension strongly reduce x RMS and a ***,the NSEs can be added to the seat suspension,and the damping coefficient of the seat suspension can also be optimized or controlled to further enhance the vehicle s ride performance.