Dinamica autobasculanta
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Transcript of Dinamica autobasculanta
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PREDEFINED DIMENSIONS
kg 1 kg s 1 s m 1 m
min 60s hr 3600s km 1000m rpm 0.1051
s
kph 1 km
hr
N 1 N W 1 W J 1 J
DEFINED DIMENSIONS
rot 2 rad rot 6.283
rpm 1 rot
min
VEHICLE WEIGHTS & MASSES
Number of seats in front Nlocf 2
Mass of one passanger m1p 75kg
Baggage mass of one passanger mb1 25kg
Vehicle mass m0 13500kg
Front seat passanger mass (without
driver) mpf Nlocf 1 m1p mpf 75kg
Back load mass mis 16500kg
Mass of all passangers mp Nlocfm1p mp 150 kg
Baggage mass mb Nlocfmb1 mb 50kg
Useful mass mu mp mb mis mu 16700 kg
Total mass of the loaded vehicle mi m0 mu mi 30200 kg
Total weight of the loaded vehicle Gi mig Gi 296160.8
Gmum0
G 1.237Weight use coefficient
DIMENSIONAL PARAMETERS OF THE VEHICLE
Wheelbase Lam 4.8m
Gauge Bec 2.3m
Total height Hin 3m
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MASSES REPARTITION - LOADED VEHICLE
Ratio between front axle weight and total weight
wi 0.22
Front axle weight
G1i wiGi G1i 65155.383 N
Back axle weight
G2i Gi G1i G2i 231005.447N
Weight on one wheel of the front axle
Gr1i
G1i
2 Gr1i 32577.691 N
Weight on one wheel of the back axle
Gr2i
G2i
2 Gr2i 115502.724 N
Horizontal length from center of gravity to back axle
bi Lamwi bi 1.056 m
Horizontal length from center of gravity to front axle
ai Lam bi ai 3.744 m
Center of gravity height
hi 1.2m
MASSES REPARTITION - UNLOADED VEHICLE
Unloaded vehicle mass
md mi mpf mis mb md 13575 kg
Unloaded vehicle weight
Gd mdg Gd 133125.274 N
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Horizontal positions of the masses with respect to the front axle
Front passanger apf 0.56m
Back load ais 2.37m
Baggage ab 0.25m
Vertical positions of the masses with respect to the front axle
Front passanger hpf 1.86m
Back load his 1.5m
Baggage hb 1.5m
Horizontal position of the center of gravity for unloaded vehicle
ad
miai mpf apf misais mbab
md
ad 5.445 m
Vertical posit ion of the center of gravity for unloaded vehicle
hd
mihi mpfhpf mishis mbhb
md
hd 0.831 m
Ratio between front axle weight and total weight:
wd
Lam ad
Lam
wd 0.134
Front axle weight
G1d wdGd G1d 17875.276 N
Back axle weight
G2d Gd G1d G2d 151000.549 N
Weight on one wheel of the front axle
Gr1d
G1d
2 Gr1d 8937.638 N
Weight on one wheel of the back axle
Gr2d
G2d
2 Gr2d 75500.275 N
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TYRE CHOICE
Highest load on one wheel
Gmax max Gr1iGr2i Gmax 115502.724 N
Based on the maximum load on the wheel, the following tyres are chosen:
285/70 R19.5, with the following characteristics:
Tyre width Btyre 285mm
Aspect ratio Asptyre 70% Asptyre 0.7
Rim diameter Djanta 19.5 in Djanta 495.3 mm
Tyre height Htyre BtyreAsptyre Htyre 199.5 mm
Free radius r0
Djanta
2Htyre r0 447.15 mm
Deformation coefficient of the tyre 0.95
Dynamic radius rd r0
rd 424.793 mm
Jr 60kg m2
Vehicle transmission characteristics
estimated efficiency est 0.90
Aerodynamic characteristi cs of the vehic le
aerodynamic drag coefficient
cx 0.7
Front surface area
Sair BecHin Sair 6.9m2
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MOVEMENT CONDITIONS
Total road resistance coefficient
f ( ) f cos ( ) sin ( )
Normal road conditions
Aerodynamic condi tions for maximum speed
Air density
air 1.225
kg
m3
Aerodynamic coefficient of the vehicle
kair
aircx
2 kair 0.429
kg
m3
Road conditi ons for maximum speed - horizontal road
v 0 grade angle
fv 0.016 rolling resistance coefficient
v fv v v 0.016 total road resistance coefficientv 0.9 grip coefficient - dry road
Roughest road conditions
maxN 17deg 100 tan maxN 30.573 % maximum grade angle
fN 0.016
maxN fN maxN maxN 0.308 total road resistancecoefficient
N 0.7
Dynamic load coefficient
Normal road conditions
mNmni
Lam
Lam Nhi cos maxN mNmni 1.159
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GRADE ABILITY
maxmm hg a atan a
Lam hg
ad 0 0.05 0.9
0 0.2 0.4 0.6 0.80
10
20
30
40
Tract. spate inc.
Tract. spate desc.
Maximum grade
maxmm adhi ai deg
maxmm adhd ad deg
ad
Resistant power and forces
Aerodynamic resistance force Rava( ) kairSair va2
Rolling resistance force Rr( ) fvGi cos ( )
Grade resistance Rp ( ) Gisin ( )
Total resistance force Rtotva ( ) Rr( ) Rp ( ) Rava( )
Air resistance power Pava( ) Rava( ) va
Rolling resistance power Prva ( ) Rr( ) va
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Grade resistance power Ppva ( ) Rp ( ) va
Ptotva ( ) Rtotva ( ) vaTotal resistant power
Necessary power for maximum speed
vmax 110km
hr
Air resistance power
Pav Pavmax Pav 84.396 kW
Rolling resistance power
Prv Prvmax v Prv 144.79 kW
Necesarry wheel power for maximum speed
PRtv Ptotvmax v PRtv 229.186 kW
Necessary engine power for maximum speed
Pvmax
PRtv
est
Pvmax 254.651 kW
The following engine is chosen:
PN 241kW
n
N
2350rpm
MM 810N m
nM 1600rpm
MN
PN
nN
MN 979.311 N m
PM MMnM PM 135.717 kW
cenMnN
ce 0.681
ca
MM
MN
ca 0.827
nmin 500 rot
min
nmax 1.07 nN nmax 2514.5 rot
min
Jm 2.4kg m2
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Np
800
900
1000
1100
1200
1300
1400
1500
1600
1700
1800
1900
2000
2100
2200
2300
2350
2400
rot
min Mp
620.14
650.20
680.59
710.30
730.56
750.89
770.45
790.34
810.20
790.34
780.23
767.98
755.20
730.43
700.43
680.23
675.65
660.54
N m
Coef cspline Np Mp( )
Mextn( ) interp Coef Np Mp n( ) Mregn( )nmax n
nmax nN MN
M n( ) if n nN Mextn( ) Mregn( )
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Engine power is obtain
P n( ) M n( ) n
SPECIFIC FUEL CONSUMPTION
The following parameters are adopted:
cN 280 gm
kW hr
specific fuel consumption at nominal engine speed
11 1.55 21 1.55 31 1
HOURLY FUEL CONSUMPTION
ChN cNPN ChN 67kg
hr Chg
ChN
3 Chg 22.493
kg
hr
c1ene cN 11 21ne
nN
31
ne
nN
2
nc nmax 20rpm
Chne if ne nN c1ene P ne Chg ChN Chg nmax ne
nmax nN
cene if ne ncChne P ne
Chnc P nc
n nminnmin 150rpm nmax
500 1000 1500 2000 25000
200
400
600
800
1000
M n( )
N m
P n( )
kW4
Chn( )kg
hr
cen( )
kg
kW hr
500
n
rpm
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TRANSMISSION EFFICIENCY
cv1 0.975 0.98 cv4 0.975 0.98 cv1 0.955
cv2 0.975 0.98 cv5 0.975 0.98 cvE 0.975
cv3 0.975 0.98
cvV 0.98 pl 0.993
Transmission efficiency:
direct drive: trV cvVpl trV 0.973trE cvEpl trE 0.968economical gear:
tr1 cv1 pl tr4 cv4 pl
tr2 cv2 pl tr5 cv5 pl tr7 trE
tr3 cv3 pl tr6 trV
Maximum speed of the vehicle
nvmax 0.98 nN nvmax 2303 rot
min
Pvmax P nvmax Pvmax 163.981 kW
Term: Av
Gi v
kairSair Av 1.602 10
3
m
s
2
Bv
trVPvmax
kairSair Bv 53940.702
m3
s3
Term:
vmax
3
Bv
2
Bv
2
2Av
3
3
3
Bv
2
Bv
2
2Av
3
3
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vmax 88.191km
hr
Transmission ratios of the gearbox
It is adopted a transmission ratio for the direct drive:
icvV 1
i0
nvmaxrd
icvVvmax i0 4.182
N 0.8
mNmni
Lam
Lam Nhi
Transmission ratio of the first gear:
trN 0.893
Gi maxN rd
MM trN i0 12.796
mNmniGi N rd MM trN i0
41.59
GimaxR rd10 3
MM trN i0 icv1
mRmniGi N rd10 3
MM trN i0
icv1 6
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q0
nN
nM 130 rot
min
q0 1.358
Necessary number of gears for starting (with no economical gear):
Ntr 1
lnicv1
icvV
ln q0
Ntr 6.85
It is adopted the number of gears including the economical gear:
Ntr 7
q
Ntr 2
icv1icvV
q 1.431
Transmission ratios of the gears:
icv1 q5
6 icv4 q2
2.048 icv71
q0.699
icv2 q4
4.193 icv5 q 1.431
icv3 q3
2.93 icv6 1
Coefficients of the masses in rotational movement:
Determining the equivalent masses:
Jmoticv masa 1Jmot icvi0
2 Jr
masa rd2
1i Jmicv1 mi 1i 1.288 1d Jmicv1 md 1d 1.641
2i Jmicv2 mi 2i 1.146 2d Jmicv2 md 2d 1.326
3i Jmicv3 mi 3i 1.077 3d Jmicv3 md 3d 1.172
4i Jmicv4 mi 4i 1.043 4d Jmicv4 md 4d 1.096
5i Jmicv5 mi 5i 1.027 5d Jmicv5 md 5d 1.06
6i Jmicv6 mi 6i 1.019 6d Jmicv6 md 6d 1.042
7i Jmicv7 mi 7i 1.015 7d Jmicv7 md 7d 1.033
ai Jm
100icv7 mi
ai 1.011 ad
Jm
100icv7 md
ad 1.025
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Speed in functi on o f the gear:
v1n( ) nrd
icv1i0 v2n( ) n
rd
icv2i0 v3n( ) n
rd
icv3i0
v4n( ) nrd
icv4i0 v5n( ) n
rd
icv5i0 v6n( ) n
rd
icv6i0
v7n( ) nrd
icv7i0
Gears changing during launching
n1min nM n1max nN n1max 2350 rot
min
n2min n1max
icv2
icv1
n2min 1642 rot
min n2max nN
n3min n2max
icv3
icv2
n3min 1642 rot
min n3max nN
n4min n3max
icv4
icv3
n4min 1642 rot
min n4max nN
n5min n1max
icv5
icv4
n5min 1642 rot
min n5max nN
n6min n1max
icv6
icv5 n6min 1642
rot
min n6max nvmax n6max 2303 rot
min
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Gear changing depending on the speed of the vehicle
v1min v1n1min v1min 10.212km
hr v1max v1n1max v1max 14.999
km
hr
v2min v2n2min v2min 14.999km
hr v2max v2n2max v2max 21.462
km
hr
v3min v3n3min v3min 21.462km
hr v3max v3n1max v3max 30.712
km
hr
v4min v4n4min v4min 30.712km
hr
v4max v4n1max v4max 43.948km
hr
v5min v5n5min v5min 43.948km
hr v5max v5n5max v5max 62.888
km
hr
v6min v6n6min v6min 62.888km
hr v6max v6n6max v6max 88.191
km
hr
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500 1000 1500 2000 25000
100
200
300
Speed characteristic
v1max
kph
v2max
kph
v3max
kph
v4max
kph
v5max
kph
v6max
kph
v1n( )
kph
v2n( )
kph
v3n( )
kph
v4n( )
kph
v5n( )
kph
v6n( )
kph
M n( )
3N m
P n( )
kW
n
rpm
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v 0km
hr 1
km
hr 1.2vmax
Traction abil ity
FR1n( )M n( ) trN i0 icv1
rd
FR2n( )M n( ) trN i0 icv2
rd
FR3n( )M n( ) trN i0 icv3
rd
FR4n( )M n( ) trN i0 icv4
rd
FR5n( )M n( ) trN i0 icv5
rd
FR6n( )M n( ) trN i0 icv6
rd
FR7n( )M n( ) trN i0 icv7
rd
0 25 50 75 100 125 150 1750
10000
20000
30000
FR1n( )
N
FR2n( )
N
FR3n( )
N
FR4n( )
N
FR5n( )
N
FR6n( )
N
FR7n( )
N
Rrv N
v1n( )
kph
v2n( )
kph
v3n( )
kph
v4n( )
kph
v5n( )
kph
v6n( )
kph
v7n( )
kph
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Power characteristic
Power at the wheel for each gear:
PR1n( ) P n( ) tr1 PR2n( ) P n( ) tr2 PR3n( ) P n( ) tr3
PR4n( ) P n( ) tr4 PR5n( ) P n( ) tr5 PR6n( ) P n( ) tr6
PR7n( ) P n( ) tr7
0 25 50 75 100 1250
31.667
63.333
95
126.667
158.333
190
Power characteristic
P n( )
kW
PR1n( )
kW
PR2n( )
kW
PR3n( )
kW
PR4n( )
kW
PR5n( )
kW
PR6n( )
kW
PR7n( )
Ptotv a kW
Ptotv d kW
v6n( )
kph
v1n( )
kph
v2n( )
kph
v3n( )
kph
v4n( )
kph
v5n( )
kph
v6n( )
kph
v7n( )
kph
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Dynamic characterist ic
D1n( )
FR1n( ) kairSair v1n( )2
Gi D2n( )
FR2n( ) kairSair v2n( )2
Gi
D3n( )FR3n( ) kairSair v3n( )
2
Gi
D4n( )FR4n( ) kairSair v4n( )
2
Gi
D5n( )FR5n( ) kairSair v5n( )
2
Gi
D6n( )FR6n( ) kairSair v6n( )
2
Gi
D7n( )FR7n( ) kairSair v7n( )
2
Gi
0 50 1000
0.1
0.2
0.3
Dynamic characteristic
D1n( )
D2n( )
D3n( )
D4n( )
D5n( )
D6n( )
D7n( )
v1n( )
kph
v2n( )
kph
v3n( )
kph
v4n( )
kph
v5n( )
kph
v6n( )
kph
v7n( )
kph
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Maximum grade depending on the gear:
max1n( ) 2 atan
1 1 fv2
D1n( )2
fv D1n( )
max2n( ) 2 atan
1 1 fv2
D2n( )2
fv D2n( )
max3n( ) 2 atan1 1 fv
2 D3n( )
2
fv D3n( )
max4n( ) 2 atan
1 1 fv2
D4n( )2
fv D4n( )
max5n( ) 2 atan1 1 fv
2 D5n( )
2
fv D5n( )
max6n( ) 2 atan
1 1 fv2
D6n( )2
fv D6n( )
max7n( ) 2 atan
1 1 fv2
D7n( )2
fv D7n( )
max1nM 7.374 deg 100 tan max1nM 12.942 %
0 50 100
0
2
4
6
8
max1n( )
deg
max2n( )
deg
max3
n( )
deg
max4n( )
deg
max5n( )
deg
max6n( )
deg
max7n( )
deg
0
v1n( )
kph
v2n( )
kph
v3n( )
kph
v4n( )
kph
v5n( )
kph
v6n( )
kph
v7n( )
kph
v
kph
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Acceleration diagram
a1n( ) gD1n( ) v
1i
a2n( ) gD2n( ) v
2i
a3n( ) gD3n( ) v
3i
a4n( ) gD4n( ) v
4i
a5n( ) gD5n( ) v
5i
a6n( ) gD6n( ) v
6i
a7n( ) gD7n( ) v
7i
0 50 100
0
0.5
1
a1n( )
m
s2
a2n( )
m
s2
a3n( )
m
s2
a4n( )
m
s2
a5n( )
m
s2
a6n( )
m
s2
a7n( )
m
s2
0
m
s2
v1n( )
kph
v2n( )
kph
v3n( )
kph
v4n( )
kph
v5n( )
kph
v6n( )
kph
v7n( )
kph
v
kph
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Engine speed for optimum launching
n1max nN
Given
a1n1max a1 n1maxicv2
icv1
=
n1max Find n1max n1max 2350 rpm
n2max nN
Given
a2n2max a2 n2maxi
cv3icv2
=
n2max Find n2max n2max 2350 rpm
n3max nN
Given
a3n3max a3 n3maxicv4
icv3
=
n3max Find n3max n3max 2350 rpm
n4max nN
Given
a4n4max a4 n4maxicv5
icv4
=
n4max Find n4max n4max 2350 rpm
n5max nN
Given
a5n5max a5 n5maxicv6
icv5
=
n5max Find n5max n5max 2350 rpmn6max nN
Given
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0 50 1000
1
2
3
avv( )
avvdem
v
kph
Launching time
Launching time depending on speed
t
d
va( )
0
va
va1
avva( )
dtdtot tdvdem tdtot 250.763 s
Launching time until 100 km/h:
td 100 km
hr
td 100
km
hr
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0 20 40 60 800
100
200
300
tdvd s
td100 kph( )
s
vd
kph
Launching space
Sdva( )
0
va
vava
avva( )
d Sdtot Sdvdem Sdtot 4539.427m
0 16 32 48 64 800
500
1000
1500
2000
2500
Sdvd m
500
1000
vd
kph
Speed at which the clutch is coupled:
v1min 10.212 kph
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Clutch slipping time:
t
d
v
1min 2.281 s
Distance until the clutch is coupled:
Sdv1min 3.235 mSpeed after 1 km after launching:
v1000 vdem
Given
Sdv1000 1000m=
v1000 Find v1000 v1000 64.254 kph
Time necessary for 1 km:
tdv1000 77.186s
Acceleration depending on launching time and space:
0 10 20 30 40 500
0.5
1
1.5
avvd m
s2
tdvd s
0 100 200 300 400 5000
0.5
1
1.5
avvd m
s2
Sdvd m
Speed depending on launching time and space:
0 50 1000
20
40
60
80
vd
kph
tdvd s
0 500 1000 1500 20000
20
40
60
80
vd
kph
Sdvd m
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BRAKING ABILITY
BRAKING DECCELERATION
Coefficient of masses in rotational movement with uncoupled clutch:
br Jm0 mi
Sum of rections at the braked wheels:
Zbr mig
Braking force: Fbr( ) Zbr
Rolling resistance force Rr( )
Drag resistance force Rava
Grade resistance force Rp ( )
Decceleration
abrva 1
brmi Fbr( ) Rr( ) Rava Rp ( )
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0 20 40 60 80
2
4
6
8abrva 0.2 0deg
m
s2
abrva 0.4 0deg m
s2
abrva 0.6 0deg m
s2
abrva 0.8 0deg m
s2
va
km
hr
BRAKING SPACE
Driver reaction time tdr 0.8sBraking system reaction time
tsys 0.54sttotal tdr tsys Considering driver reaction timeTotal reaction time:ttotal2 tsys Neglecting driver reaction time
Braking space:
sstopva vattotal brmi
0
va
va
va
Fbr( ) Rr( ) Rava Rp ( )
d
sstop2va vattotal2 brmi
0
v
ava
va
Fbr( ) Rr( ) Rava Rp ( )
d
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0 10 20 30 40 50 60 70 80 90 100
25
50
75
100
125
150
175
200
225
250
sstopva 0.2 0deg
m
sstopva 0.4 0deg m
sstopva 0.6 0deg m
sstopva 0.8 0deg m
sstop2va 0.2 0deg
m
sstop2va 0.4 0deg m
sstop2va 0.6 0deg m
sstop2va 0.8 0deg m
va
km
hr
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CORNERING STABILITY
Critical slipping speed:
vdRv Rvg tan ( )
1 tan ( )
g gravity acceleration
Rv steering radius
transversal inclination of the road
grip coefficient
B.ec gauge
hg center of gravity height
0 50 100 150 200
20
40
60
80vdRaza 0deg 0.8( )
km
hr
vdRaza 0deg 0.6( )
km
hr
vdRaza 0deg 0.4( )
km
hr
vdRaza 0deg 0.2( )
km
hr
Raza
m
SPEED AT WHICH THE LOADED VEHICLE
TURNS OVERS
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vrlR ( ) R g
Bec
2hitan ( )
1Bec
2hi
tan ( )
SPEED AT WHICH THE UNLOADED
VEHICLE TURNS OVER
vrR ( ) R g
Bec
2hd
tan ( )
1Bec
2hd
tan ( )
0 50 100
20
40
60
80
Descarcat
Incarcat
vrRaza 0deg( )
km
hr
vrlRaza 0deg( )
km
hr
Raza
m
-
8/13/2019 Dinamica autobasculanta
31/34
N
-
8/13/2019 Dinamica autobasculanta
32/34
-
8/13/2019 Dinamica autobasculanta
33/34
3
va
ri3
a4
va
ri4
if va v
5max a
5
va
ri5
a
6
va
ri6
-
8/13/2019 Dinamica autobasculanta
34/34