Current Issue : January - March Volume : 2021 Issue Number : 1 Articles : 5 Articles
The friction of the orbiting scroll leads to large power consumption and low energy\nefficiency of the scroll compressor. The common methods to solve this problem are high cost and\na complex process. Considering special structures and operating principles to apply the coating\ntechnology on the scroll compressor is a new subject. Given the material of the orbiting scroll being\naluminum alloy, the unbalanced magnetron sputtering technology for the orbiting scroll of the scroll\ncompressor was chosen and the Cr transition layer was coated to enhance the bonding strength.\nMoreover, we innovatively performed an experiment to verify the feasibility of unbalanced magnetron\nsputtering film coating technology for the diamond-like carbon film coated in the scroll compressor.\nThis article elaborates the parameter test methods of the film properties before and after experiments\nand the experimental system components. The results showed that the diamond-like carbon film\nhas low coefficient and high bonding strength, which renders it a good wear-reducing effect and an\nexcellent self-lubricating property. Due to the thin film layer and high operating temperature, the\nthickness should be increased to raise the abrasion resistance. The refrigeration system with the scroll\ncompressor coated with the diamond-like carbon film can satisfy the national standard conditions\nwith low Vickers hardness. Its performance was improved at low speed. Therefore, the unbalanced\nmagnetron sputtering with increased Cr bond layer is a feasible and appropriate technology for\ncoating diamond-like carbon film....
Fatigue life prediction is an important part of the reliability and durability analysis of automobile components. Based on Wang\nand Brownâ??s framework, multiaxial random fatigue damage was adopted to predict the fatigue life of half-shaft. The stress analysis\nof half-shaft was resolved analytically to determine the local stress tensor in the potential area of fracture. The maximum shear\nstrain fatigue damage parameter and the normal stress fatigue damage parameter were evaluated to predict the fatigue life of halfshaft.\nThe results show that the prediction method is reliable and meets the service life and safety requirements....
This paper proposes an algorithm for modeling a three-dimensional tethered environment for testing vertical-take off, vertical\nlanding vehicles. The method is able to take several geometrical configurations into account and combines the classical catenary\nmodel with the elasticity theory to predict the forces acting on the lander in quasistatic conditions, i.e., in conditions of\nhovering, where the motion of the vehicle is reduced. Numerical results confirm that the method is potentially able to provide\nreal-time solutions, which can be included as feedforward contributions in the design of tethered experiments....
The optimization of high-occupancy vehicle (HOV) lane management can better improve the efficiency of road resources. This\npaper first summarized the current research on HOV lane implementation and analyzed and identifies the threshold of setting\nroad HOV lane dynamic control under the connected vehicle environment. Then, the HOV lane priority dynamic control process\nwas determined, and the operating efficiency and energy consumption evaluation method was proposed. Moreover, a case study in\nWuxi City, China, was carried out. The results showed that, after implementing the HOV lane priority dynamic control, the total\nmileage of road network vehicles was saved by 4.93%, the average travel time per capita was reduced by 4.27%, and the total\nenergy-saving rate of road network travel was 21.96%....
According to the accident analysis of vehicles in the curve, the skidding, rollover, and lateral drift of vehicles are determined as\nmeans to evaluate the lateral stability of vehicles. The utility truck of rear-wheel drive (RWD) is researched, which is high accident\nrate. Human-vehicle-road simulation models are established by CarSim. Through the orthogonal experiment method, the effects\nof different road geometries, speed, and interaction factors between road geometries on vehicle lateral stability are studied. In this\npaper, skidding risk of the vehicle is characterized by the Side-way Force Coefficient (SFC). Rollover risk of the vehicle is\ncharacterized by lateral acceleration and the load transfer ratio. Lateral drift risk of the vehicle is characterized by the sideslip angle\nof wheels. The results of orthogonal analysis reveal that the maximum tire-road friction coefficient and speed are highly significant\nin skidding of the vehicle. The effects of the combination of horizontal alignment and superelevation on vehicle skidding are\nimportant. The effects of horizontal alignment and speed on vehicle rollover risk are highly significant. The effects of superelevation\non vehicle rollover risk are significant. The effects of the interaction of horizontal alignment and superelevation are also\nimportant on vehiclesâ?? rollover risk. The speed and the maximum tire-road friction coefficient have highly significant effect on the\nvehicleâ??s lateral drift. The superelevation has a significant effect on the vehicleâ??s lateral drift. The effects of the interaction of\nhorizontal alignment and superelevation and longitudinal slope are also important on the lateral drift of the vehicle....
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