外文翻譯--黏性連接器用作前輪驅(qū)動限制滑移差速器對汽車牽引和操縱的影響-汽車設計(存儲版)
【正文】 travel radii, the rotational differences especially at high speeds are large enough for a viscous coupling front differential to bring improvements in straightline running. High powered frontwheel drive vehicles fitted with open differentials often spin their inside wheels when accelerating out of tight corners in low gear. In vehicles fitted with limitedslip viscous differentials, this spinning is limited and the torque generated by the speed difference between the wheels provides additional tractive effort for the outside driving wheel. this is shown in figure 12 Figure 12: tractive forces for a frontwheel drive vehicle with viscous limitedslip differential during acceleration in a bend The acceleration capacity is thus improved, particularly when turning or accelerating out of a Tjunction maneuver ( . accelerating from a stopped position at a “T” intersectionright or left turn ). Figures 13 and 14 show the results of acceleration tests during steady state cornering with an open differential and with viscous limitedslip differential . Figure 13: acceleration characteristics for a frontwheel drive vehicle with an open differential on wet asphalt at a radius of 40m (fixed steering wheel angle throughout test). Figure 14: Acceleration Characteristics for a FrontWheel Drive Vehicle with Viscous Coupling on Wet Asphalt at a Radius of 40m (Fixed steering wheel angle throughout test) The vehicle with an open differential achieves an average acceleration of 2/sm while the vehicle with the viscous coupling reaches an average of 2/sm (limited by enginepower). In these tests, the maximum speed difference, caused by spinning of the inside driven wheel was reduced from 240 rpm with open differential to 100 rpm with the viscous coupling. During acceleration in a bend, frontwheel drive vehicles in general tend to understeer more than when running at a steady speed. The reason for this is the reduction of the potential to transmit lateral forces at the fronttires due to weight transfer to the rear wheels and increased longitudinal forces at the driving wheels. In an open loop controlcircletest this can be seen in the drop of the yawing speed (yaw rate) after starting to accelerate (Time 0 in Figure 13 and 14). It can also be taken from Figure 13 and Figure 14 that the yaw rate of the vehicle with the open differential fallsoff more rapidly than for the vehicle with the viscous coupling starting to accelerate. Approximately 2 seconds after starting to accelerate, however, the yaw rate falloff gradient of the viscouscoupled vehicle increases more than at the vehicle with open differential. The vehicle with the limited slip front differential thus has a more stable initial reaction under accelerating during cornering than the vehicle with the open differential, reducing its understeer. This is due to the higher slip at the inside driving wheel causing an increase in driving force through the viscous coupling to the outside wheel, which is illustrated in Figure 12. the imbalance in the front wheel tractive fo
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