《汽车理论》课程教学课件（英文讲稿）第1章 汽车动力性 Acceleration Performance 1.5 Power Equilibrium

S1.5PowerEquilibriumP+P+PP, =P.LP1.Equation ofPowerEquilibrium:lossP=P,+Pw+P+PFOS.DPw+P+P,)nr2.HowtomaketheGraphofPowerEquilibrium（功率平衡图）：because :POWER(W) = FORCE(N)×v(m / s)P,+Pw+P+P)nT1FuaP(kW)= F(N)×u (km / h)×100036003600100011WaP(F,+F,+Fw+F))3600nr.Au福oWaduPGf cos α +-Gsinα+e3600nr21.15dtgChapter1AccelerationPerformance

Chapter 1 Acceleration Performance §1.5 Power Equilibrium 1.Equation of Power Equilibrium： 2. How to make the Graph of Power Equilibrium (功率平衡图）: because : 1 ( ) e f W i j loss e loss f W i j e f W i j T P P P P P P P P P P P P P P P P P                POWER W FORCE N v m s ( ) ( ) ( / )   2 ( ) 3600 ( cos sin ) 3600 21.15 a e f i W j T a D a e T u P F F F F u C A u du P Gf G G g dt                  1 1 ( ) e f W i j T P P P P P      ( / ) 1000 1 ( ) ( ) 3600 1000 3600 a a u km h F u P kW F N      

S1.5 Power EquilibriumPr+PwP,+PwnTPe50Nr45FIV··umItqg1aP40Wae1nr35aY/302520节气门部分开启abreservesupplyof15bpower（后备功率）105c050150100uupiuaamaxua / (km·h-)2Chapter1AccelerationPerformance

Chapter 1 Acceleration Performance §1.5 Power Equilibrium 0 f W T t a tq g e a T P P F u T i i P u r                 │ab│—reserve supply of power(后备功率) 2

PP, kWPw+nTII1nII-reservesupplyfpower后备功率partialpower部分油门开度km/hu.,uuamaxaGraphof PowerEquilibrium3Chapter1AccelerationPerformance

Chapter 1 Acceleration Performance Pe ，kW km/h a u ， u amax 'a u Pe f W T P P  I II III IVpartial power 部分油门开度 reservesupply of power 后备功率 abC Graph of Power Equilibrium 3

GraphofPower EquilibriumforAudi-A4120Pe1100Pe2Pe3M/dPe4Pe540Pe60阻力功率310u, /(km·h-l)4Chapter1AccelerationPerformance

Chapter 1 Acceleration Performance 0 20 40 60 80 100 120 0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200 210 220 230 240 250 260 270 280 290 300 310 P/kW Pe1 Pe2 Pe3 Pe4 Pe5 Pe6 阻力功率 1 a u /(km h )   Graph of Power Equilibrium for Audi-A4 4

Reservesupplyofpower50II40III30VIV2010015050100a / (km·h-l)5Chapter1AccelerationPerformance

Chapter 1 Acceleration Performance Reserve supply of power 5

3.Analyze the evaluationlndex ofacceleration performancewithPowerEquilibriumGraph(l) uamax is the corresponding x-coordinate of the crosspoint of the resistance power curve and the full powercurve of the fourth (high-speed) gear(2) The reverse supply of power changes with thechange of gear.------ Higher gear leads to lower reversesupply of power and acceleration ability6Chapter1 AccelerationPerformance

Chapter 1 Acceleration Performance uamax 3. Analyze the evaluation Index of acceleration performance with Power Equilibrium Graph (1) is the corresponding x-coordinate of the cross point of the resistance power curve and the full power curve of the fourth (high-speed) gear. (2) The reverse supply of power changes with the change of gear.- Higher gear leads to lower reverse supply of power and acceleration ability. 6

Chapter 1AccelerationPerformance汽车动力性福园国国1.0Forward(引言）1.1EvaluationIndex（评价指标）1.2DrivingMechanicsofVehicle（汽车驱动力和行驶阻力)1.3TractiveForce&DrivingResistanceSpeedCharacteristics andDynamicCharacteristics（驱动力行驶阻力平衡图与动力特性图）l.4 Traction-Limited Acceleration and AdhesionRatio（汽车驱动-附着条件及附着率）1.5PowerEquilibrium（汽车的功率平衡）7Chapter1 AccelerationPerformance

Chapter 1 Acceleration Performance Chapter 1 Acceleration Performance 汽车动力性 1.0 Forward(引言) 1.1 Evaluation Index(评价指标) 1.2 Driving Mechanics of Vehicle(汽车驱动力和行驶阻 力) 1.3 Tractive Force & Driving Resistance—Speed Characteristics and Dynamic Characteristics（驱动力 -行驶阻力平衡图与动力特性图） 1.4 Traction-Limited Acceleration and Adhesion Ratio(汽车驱动-附着条件及附着率) 1.5 Power Equilibrium(汽车的功率平衡) 7