1. Table of running resistances – PSA proposal
WLTP-DTP-LabProcICE-167
Table of running resistances – PSA proposal
Bertrand MERCIER
November 2012

2. Using the table of running resistances
The table of running resistances is necessary for the multi-stage vehicles
These are N1 vehicles
Are M1 vehicles using this table ?
How is done the dyno setting ?
Set the dyno with 3 coefficients a, b and c
F = a + b v + c v²
a is a constant in N
b is in N/(km/h)
c is in N/(km/h)²
Put the vehicle on the dyno

3. Proposed approach
The road load of the vehicle is due to several effects
Aerodynamic
Mechanical losses (Front and Rear)
Tires rolling resistance (Front and Rear) A C1 C2 B1 B2
TIRE ROLL. REST.
Aerodynamic
Mech. Loss.

4. Proposed approach On the dyno, the vehicle is submit to several forces
And the dyno is used to simulate
Aerodynamics
Rear tires rolling resistances (nondriving axle)
Rear axle mechanical losses (nondriving axle) C2 B2
Aerodynamic
Mech. Loss. B1 A C1
TIRE ROLL. REST.

5. Proposed approach C1 B1

6. Proposed approach Aerodynamics A
The coefficient c is comming from aerodynamics (1/2 ρ SCx v²)

7. Evaluation of the position of N1 vehicles
Evaluation of aerodynamics on several vehicles
3 types of N1 vehicles (only vans)
F1 (Berlingo/Partner)
K1 (Jumpy/Expert)
K2/K3 (Jumper/Boxer)
For each type , 3 shapes : mini ; medium; maxi
For each type and shape :
The test mass , average of market distribution
The Aerodynamics, worst case on the vans
Vehicle
Test Mass (kg)
Aero (m²)
½ ρ SCx (N/(km/h)²)
F1 mini
1713
1,21
0,0552
F1 medium
1784
1,25
0,0571
F1 maxi
1881
1,35
0,0616
K1 mini
2141
1,41
0,0644
K1 medium
2250
1,46
0,0666
K1 maxi
2318
1,51
0,0689
K2/K3 mini
2411
K2/K3 medium
2578
1,73
0,0790
K2/K3 maxi
2965
2,1
0,0958

8. Evaluation of the position of N1 vehicles
Positionning of the 9 « vehicles »

9. Evaluation of the position of N1 vehicles
Positionning of the 9 « vehicles »

10. Proposal for the a , b and c coefficients
F = a + b * v + c * v²
a coefficient
a = F(RRC) + F(Brake) in N
a = 0,06 * TM in N
Where TM is TMH or TML in kg
b coefficient
b = 0,1 in N/(km/h)
c coefficient
c = 1/2 ρ SCx in N/(km/h)²
c = 0, (-5,06E-05) * TM + (1,75E-08) * TM² in N/(km/h)²

11. Proposal for the a , b and c coefficients
Illustration
F = a + b * v + c * v²

12. Conclusion Proposal Issues To Use this new ‘table’
To Apply a factor of 1,1 (10%) to insure that the table wont be used for common vehicles
Issues
Is this table necessary for M1 vehicles ?
Need some more datas for heavyer vehicles
Opposite concavity