slide thuyết trình kia carnival

Calculation of automotive dynamics parameters4.1 Calculation of gear ratiosa Main gear ratioDetermined by conditions that ensure the car moves at the maximum speed at hand highest gear o

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I.Introduction to the car model

• Carnival is the most versatile, comfortable and luxurious urban SUV in the

Vietnamese market, combining the

dynamism and

robustness typical of SUVs with luxurious and comfortable

space, applying many modern technologies to create a new

standard in the SUV segment.

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II Linear layout

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III Input parameters

Table 1.1 Basic parameters

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3.1 ) Parameters according to the sketch Design

Engine type: gasoline engine, GAS 3.5

- Working capacity: Vc = 3470 (cc)

–Maximum power: Pmax = 268(horsepower) = 164 (kW)–nN = 5400 ()

–Maximum torque: Mmax =331 (N.m)

–Maximum velocity: vmax = 200 (km/h) =55.56 (m/s)–Powertrain:

–+ Active 2-wheel front-mounted engine–+ 6-speed manual transmission.

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Self-weight: 2125 kg.Passenger weight: 70 kg/person.Baggage weight: 20 kg per person.Power transmission efficiency: η_tl=0.9.tl=0.9.

Air resistance coefficient: K=0.18.–Rolling resistance coefficient when V<22 m/s :

3.2 Selection parameters

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3.3) Selection calculation parameters

The road resistance coefficient corresponds to Vmax = 55.56m/s=>f=f_tl=0.9.0 (1+ 〖 V_tl=0.9.max 〗 ^2/1500)

Wheel radius : 235/55R19 =>H/B=55% H=235.55%=129.25 (mm)=>r0 = 129.25+ 19/2 25.4 = 370 (mm) = 0.37 (m)Kinetic radius and dynamic radius of wheels:

rđ = rk = λ.r0 =>rđ = rk = 0.93 0.37 ≈0.34 (m).

Main bumper area :F = 0.7.B0 H0 = 0.7.1,995.1,775 = 2.2 (m^2 )4x4 wheel formula

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3.4 Determine the weight and distribution of weight on the carKia Carnival 7-seater:

G = G0 + n.(A + Gh)

+ Self-esteem (self-weight): G0 = 2125 (kG)

+ Load capacity (cargo, luggage, ): Gh = 20 (kG)+ n – Number of people (n = 7) + A = 70kg – Mass of people

=>G = 1875 + 7.( 70+ 20) = 2755 (kG) =27550(N)

Passenger cars acting on the front axle (G2) account for 40% ÷ 45% Select G2 = 40%GG2 = 40% 2755= 1102 (kG) = 11020(N)

 G1 = 2755-1102= 1653(kG) = 16530(N)– Vậy G2 = 11020 (N); G1 = 16530(N).

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IV External character line construction of engine

*Motor power corresponds to vmaxNev = với = = 0,031

Nev = (W)

Nev = 127472(W) =127,5(KW).*Maximum capacity

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IV Construction of the outer characteristic line of the engine

+ The value Me max is determined by the Laydecman formula as follows::Derived from the formula

Nemax = 1,1.Nemax = 1,1 130206.3 = 143226.93(W)

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IV Construction of the outer characteristic line of the engine

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IV Calculation of automotive dynamics parameters

4.1 Calculation of gear ratios

a) Main gear ratio

Determined by conditions that ensure the car moves at the maximum speed at hand highest gear of the gearbox.Ta có:

i0 = (CT3-8 [1])(2.6)Where:

+ rbx = 0,37 (m)

+ Engine speed corresponding to Vmax+ Pass score of the last number hand+ : Maximum engine velocity i0 == 3,83

So the gear ratio of the power transmission is: i0 = 3,83

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4.2 Gear ratio

b) Gear 1

Pk max = Pψ maxψmax.G

Test the grip of the pavement wheels:

= 3,8 =7,36(satisfying the clinging condition)So the gear 1 ratio is: = 3,8

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c) Largest gear ratio and smallest gear ratio

The largest gear ratios are

The smallest gear ratio is

= 3,485

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d) intermediate gear ratio

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4.3.xây dựng đò thị lực kéo của oto

Pki = =

Pc = G.f + KFv²

Pφ =G.mp.φ

• Pki : traction in the gear arms;

• Mki : tensile torque at the gear arms;• Me :Traction torque at the engine• io :Main gear ratio

• ihn :Gear ratios at different levels• :Power transmission efficiency• G: Weight of the car

• f:rolling resistance coefficient• F:Frontal bumper area

• V:velocity at the gear arms;• Φ:Line adhesion coefficient• mp:Line adhesion coefficient

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4.3 build automobile traction graphs

Traction graph corresponding to each number hand

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Table 2.4 Resistance value for each number hand

Pc330.6430.9909 498.52496 613.9433807.69771136.5161690.134

Pφ6942.66942.66942.66942.66942.66942.66942.6

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Observe:

+ The vertical axis represents Pk , Pf , Pw Representation horizontal axis v (m/s)+ The traction graph of the car Pki = f(v) is similar to the curve form Me = f(ne) of the external speed characteristic line of the engine.+ The limit between the Pki drag curve and the total drag curve is the residual traction force (Pkd) used for acceleration or climbing.+ The total traction force of the car must be less than the grip force between the wheel and the road surface

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VII.Tính toán các thông số động lực học ô tô

7.4 Xây dựng đồ thị công suất kéo

bumpers of the road

• V:velocity at the gear arms;• Nc: bumper power

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4.4 Build a traction capacity graph

Table 2.5 Automotive Power Table

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4.4 Build a traction capacity graph Table 2.6 The bumper of the car corresponds to each gear hand

Ne(kW)07.20871311.28060918.99843 34.11817 65.22106 130.3659

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4.5 Building dynamic graphs

Di = (-KFv²)

2w k

PPmGK F VD

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4.5) Building dynamic graphs

Table 2.7.Dynamics factors

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Table 2.8 Dynamics factors according to attachment conditions

Dφ0.28-0.003644-0.006095 -0.010285 -0.017318-0.029253 -0.049348f0.0120.01380.0150109 0.017080.0205540.026450.036376

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4.6) determine the acceleration capacity of the automobile –and build an accelerator

VII Calculation of automotive dynamics parameters

Ji = g

+ Di – the dynamic factor value in the ith hand corresponds to the known vi rate from the graph D = f(v);

+ f, i – coefficient of rolling resistance and slope of the road;

+ ji – The acceleration of the car in the i-th hand.

+ is the coefficient that takes into account the influence of the mass of rotation

= 1+0,05(1+ihi²) (CT 1-37 [1])

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Table 2.10 The acceleration value corresponding to each number hand

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– + In the speed range from 0 to vmin the car starts to depart, at that time, the clutch slips and the throttle opens gradually.

– + At vmax = 58.33 (m / s), jv = 0, then the car is no longer able to accelerate.

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V Lập bảng tính giá trị thời gian tăng tốc – quãng đường tăng tốc của ôtô

dS = v.dt →

5.1 Cách tính thời gian tăng tốc – quãng đường tăng tốc của ôtô

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V Make a spreadsheet of the value of acceleration time – the acceleration distance of the car

–Considering the loss of speed and time when changing gears.

Δv = (m/s)

+ f – hệ số cản lăn của đường f = f0∗ ቀ1 + V2

1500ቁ + g = 9,81 (m/s2) – gia tốc trọng trường

+ ∆t =1– thời gian chuyển số [s] + δj ≈1

5.1 How to calculate acceleration time – the acceleration distance of the car

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VII Evaluate the ability to pull hooks and cross hills

7.1) Hill climbing ability -0,012=0,44 =44%

ÞThe vehicle has good hill climbing ability5.2) Trailer towing capability