《汽车理论》课程教学课件（英文讲稿）第5章 汽车操纵稳定性 Handling Performance 5.2 Tire Cornering Property（轮胎侧偏特性）

（轮胎侧偏特性5.2 Tire Cornering Property侧偏角α2l.Tire Axis SystemAligning torque轮胎接地印迹中心的轮胎坐标系正回正力矩T，位移方向与轴的夹角Ycamber angle正外倾角Y车轮行驶方向1P-车轮平面0正TySlipangle正侧偏角0Overturntorque车轮旋转轴线正翻转力矩Tx正地面切向正地面侧向反作用力F反作用力Fx正地面法向反作用力Fz

α O X Y 车轮行驶方向 正地面切向 反作用力FX Overturn torque 正翻转力矩 TX 正地面法向 反作用力FZ 正地面侧向反作用力FY 车轮旋转轴线 slip angle 正侧偏角 Aligning torque 正回正力矩TZ 正TY camber angle 正外倾角γ γ Z 侧偏角α 轮胎接地印迹中心的 位移方向与X轴的夹角 1.Tire Axis System 轮胎坐标系 5.2 Tire Cornering Property （轮胎侧偏特性

l.Tire Axis System轮胎坐标系X-axis-The intersection of the wheel planeand the road plane with the positive directionforward.Y-axis-The projection of wheelrotating axisontheroad plane.Z-axis-The Z-axis is perpendicular to theroad plane with upward direction

X-axis—— The intersection of the wheel plane and the road plane with the positive direction forward. Y-axis—— The projection of wheel rotating axis on the road plane. Z-axis——The Z-axis is perpendicular to the road plane with upward direction. 1.Tire Axis System 轮胎坐标系

2. Tire Slip and Slip anglerigidtire侧偏现象和侧偏角VCornering Force侧偏力FuUuLateral Force侧向力FSlip angel侧偏角αF,=kαVFFV1CorneringStiffnessFyF侧偏刚度kF,≤FF,>≥(0,F

u u u' v Fy Fy C C rigid tire F F y l z ≤  F F y l z ＞  FY FY Fy FY Y y Y F F F k k   Cornering Force侧偏力 Lateral Force侧向力 Slip angel侧偏角 ＝ Cornering Stiffness 侧偏刚度 2.Tire Slip and Slip angle 侧偏现象和侧偏角

pneumatic tire弹性轮胎overhead viewF俯视图Fy17777Ahwheelstillness车轮静止

overhead view 俯视图 wheel stillness 车轮静止 F y pneumatic tire 弹性轮胎 FY

pneumatic tire弹性轮胎WwFA4A.A3A2AFwheel roll车轮滚动

F y wheel roll 车轮滚动 FY pneumatic tire 弹性轮胎

Slipangle?The angle between the direction of X axis anddirection of tire imprinting center0HXFV+α:

α 0 X Y FY FY：“+”，α： “-” u - + α Slip angle——α The angle between the direction of X axis and direction of tire imprinting center u

Tire SlipWhen a rolling pneumatic tire is subjected to alateral force, the tire will drift to the side. Thisphenomena is called Tire Slip. An angel will becreated between the direction of X axis of tireaxis system and the direction of travel. Thise一α（侧偏角）angel is known as slip angleInflation pressure , load and centrifugal forceinfluencethe Slip Angle

 When a rolling pneumatic tire is subjected to a lateral force, the tire will drift to the side. This phenomena is called Tire Slip. An angel will be created between the direction of X axis of tire axis system and the direction of travel. This angel is known as slip angle ——α （侧偏角）.  Inflation pressure , load and centrifugal force influence the Slip Angle. Tire Slip

Tire Slip275/30ZR19

Tire Slip 275/30 ZR19

3.Testing results about the variables which affectTireSlip（影响轮胎侧偏特性各因素的试验结果）(1) Cornering force——Fy, (lateral force——F,)F, 个= distortion 个= slip angle(α) 个aFy-7000k=aα-6000-5000where:kCornering StiffnessNIX-4000（侧偏刚度）3000FyLateral (cornering) force215-R15（侧偏力）-2000p:196.2kPaα一一SlipAngle（侧偏角）-1000上4121o68012a/()

where：k —— Cornering Stiffness （侧偏刚度） FY —— Lateral (cornering) force （侧偏力） α —— Slip Angle (侧偏角） F distortion slip angle Y    （） FY k     3. Testing results about the variables which affect Tire Slip （影响轮胎侧偏特性各因素的试验结果） （1）Cornering force—— FY , (lateral force——Fy )

(2) TireBType :kradialpy>kbias-plyH子午斜交Width扁平率：(Aspect ratio)RHFlat - Ratio=B扁平率=（H/B）X100% (宽胎）> For broad tirelow flat ratio → k↑>For narrow tire（窄胎）high flat ratio → kl

• Type ： • Width （Aspect ratio) 扁平率： 子午 斜交 radial ply＞ bias ply k k   B H Flat  Ratio  （2）Tire  For broad tire （宽胎） low flat ratio → k↑  For narrow tire（窄胎） high flat ratio → k↓