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Wheels Vehicle Simulation

Input Parameters
Curb Weight:1500 kg
Payload:75 kg
Drag Coefficient:0.3
Frontal Area:2.5 m2
Rolling Resistance Coefficient:0.01
Wheel Diameter:1 m
Rotation Factor:1
Grade0 percent
Air Density:1.2 kg/m3
Ave. engine efficiency:90 percent
Ave. drivetrain efficiency:90 percent
Ave. regen efficiency:90 percent
Fuel heating value:114132 btu/gal
Driving Cycle:FTP


Energy Breakdown - FTP Cycle
Total energy demanded at wheels:8163958.30 J (2.2678 kWh)
 Consumed by Aerodynamic Drag:2045776.08 J (25.05 %)
 Consumed by Rolling Resistance:2744397.40 J (33.61 %)
 Consumed by Braking:3373784.81 J (41.32 %)
Distance traveled:11.04 miles
Gross efficiency:739.39 kJ/mile (0.2054 kWh/mile)
Gross thermal fuel economy (at wheels):162.75 mi/gal
Net fuel economy (engine 90%, drivetrain 90%):131.83 mi/gal
With regenerative braking at 90 percent:209.89 mi/gal
Time in Idle:335 sec
Time in Acceleration:739 sec
Time in Powered Deceleration:193 sec
Time in Cruise:145 sec
Time in Braking:462 sec
This accounts for 1874 of 1874 seconds in the cycle.



Plot
Key:
Velocities (bold green)
aero power (thin red)
rolling resistance power (thin black)
braking power (thin blue)
cumulative aero energy (bold red)
cumulative rolling resistance energy (bold black)
cumulative braking energy (bold blue)

Scale: 1 vertical square = 2 kW (power) or 0.2 MJ (energy) or 10 mi/hr. Time: 1 horizontal square = 20 seconds. Each square is 20x20 pixels.
Any values beyond the vertical extent of the chart are cut off.

This image is deleted from the server shortly after it is generated. To save it, drag it to the desktop. Or, make a nicer chart by downloading the data below to a spreadsheet.



Potential mi/gal on FTP Cycle
The cells in the matrix indicate the potential fuel economy of this vehicle (mi/gal) as a function of average regenerative braking efficiency (horizontal) and average fuel-to-wheels efficiency (vertical). The fuel-to-wheels efficiency is the average efficiency with which fuel energy is converted to work and transmitted to the wheels. It includes the engine and drivetrain efficiencies. For anything powered by an internal combustion engine, only values well under 40% could be considered realistic.

Average Regen efficiency (% entering regen system * RT component efficiency)
1.00 0.95 0.90 0.85 0.80 0.75 0.70 0.65 0.60 0.55 0.50 0.45 0.40 0.35 0.30 0.25 0.20 0.15 0.10 0.05 0.00
Average
Fuel-to-wheels
efficiency
1.00277.57268.13259.31251.05243.30236.01229.15222.68216.56210.77205.28200.07195.12190.40185.91181.63177.54173.63169.88166.30162.86
0.95263.69254.72246.34238.50231.13224.21217.70211.55205.73200.23195.02190.07185.36180.88176.62172.55168.66164.95161.39157.99154.72
0.90249.81241.32233.38225.94218.97212.41206.24200.41194.90189.69184.75180.06175.61171.36167.32163.47159.78156.26152.90149.67146.58
0.85235.94227.91220.41213.39206.80200.61194.78189.28184.08179.15174.49170.06165.85161.84158.03154.38150.91147.58144.40141.36138.43
0.80222.06214.50207.45200.84194.64188.81183.32178.14173.25168.62164.22160.06156.09152.32148.73145.30142.03138.90135.91133.04130.29
0.75208.18201.10194.48188.29182.47177.01171.86167.01162.42158.08153.96150.05146.34142.80139.43136.22133.15130.22127.41124.73122.15
0.70194.30187.69181.52175.73170.31165.21160.41155.88151.59147.54143.70140.05136.58133.28130.14127.14124.28121.54118.92116.41114.00
0.65180.42174.28168.55163.18158.14153.41148.95144.74140.76137.00133.43130.05126.83123.76120.84118.06115.40112.86110.43108.10105.86
0.60166.54160.88155.59150.63145.98141.61137.49133.61129.94126.46123.17120.04117.07114.24111.55108.98106.52104.18101.9399.7897.72
0.55152.66147.47142.62138.08133.81129.81126.03122.47119.11115.92112.90110.04107.31104.72102.2599.9097.6595.4993.4491.4789.58
0.50138.79134.06129.65125.52121.65118.01114.58111.34108.28105.39102.64100.0497.5695.2092.9690.8188.7786.8184.9483.1581.43
0.45124.91120.66116.69112.97109.48106.21103.12100.2197.4594.8592.3890.0387.8085.6883.6681.7379.8978.1376.4574.8473.29
0.40111.03107.25103.72100.4297.3294.4191.6689.0786.6284.3182.1180.0378.0576.1674.3772.6571.0269.4567.9566.5265.15
0.3597.1593.8590.7687.8785.1582.6180.2077.9475.8073.7771.8570.0268.2966.6465.0763.5762.1460.7759.4658.2157.00
0.3083.2780.4477.7975.3172.9970.8068.7566.8064.9763.2361.5860.0258.5457.1255.7754.4953.2652.0950.9749.8948.86
0.2569.3967.0364.8362.7660.8259.0057.2955.6754.1452.6951.3250.0248.7847.6046.4845.4144.3843.4142.4741.5840.72
0.2055.5153.6351.8650.2148.6647.2045.8344.5443.3142.1541.0640.0139.0238.0837.1836.3335.5134.7333.9833.2632.57
0.1541.6440.2238.9037.6636.4935.4034.3733.4032.4831.6230.7930.0129.2728.5627.8927.2426.6326.0425.4824.9524.43
0.1027.7626.8125.9325.1024.3323.6022.9222.2721.6621.0820.5320.0119.5119.0418.5918.1617.7517.3616.9916.6316.29
0.0513.8813.4112.9712.5512.1611.8011.4611.1310.8310.5410.2610.009.769.529.309.088.888.688.498.328.14
0.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.00


Average efficiencies necessary for 100 mi/gal on FTP Cycle
The cells in the matrix indicate the average engine efficiency necessary to achieve 100 mi/gal, as a function of average regenerative braking efficiency (horizontal) and average drivetrain efficiency (vertical). The drivetrain is the portion of the powertrain downstream of the engine output. For a conventional vehicle, the engine efficiency is the average efficiency achieved in meeting the highly variable road load. Reasonable values would be significantly lower than the engine's peak efficiency. For series hybrid vehicles, an efficiency closer to the peak efficiency may be reasonable to consider, and the average drivetrain efficiency represents the efficiency with which energy from the engine is successfully delivered to the wheels - including, of course, the roundtrip efficiencies for any portion of that energy that passes through a storage medium on the way, such as a battery.

Average Regen efficiency (% entering regen system * RT component efficiency)
1.00 0.95 0.90 0.85 0.80 0.75 0.70 0.65 0.60 0.55 0.50 0.45 0.40 0.35 0.30 0.25 0.20 0.15 0.10 0.05 0.00
Average
Drivetrain
efficiency
1.000.360.370.390.400.410.420.440.450.460.470.490.500.510.530.540.550.560.580.590.600.61
0.950.380.390.410.420.430.450.460.470.490.500.510.530.540.550.570.580.590.610.620.630.65
0.900.400.410.430.440.460.470.480.500.510.530.540.560.570.580.600.610.630.640.650.670.68
0.850.420.440.450.470.480.500.510.530.540.560.570.590.600.620.630.650.660.680.690.710.72
0.800.450.470.480.500.510.530.550.560.580.590.610.620.640.660.670.690.700.720.740.750.77
0.750.480.500.510.530.550.560.580.600.620.630.650.670.680.700.720.730.750.770.780.800.82
0.700.510.530.550.570.590.610.620.640.660.680.700.710.730.750.770.790.800.820.840.860.88
0.650.550.570.590.610.630.650.670.690.710.730.750.770.790.810.830.850.870.890.910.930.94
0.600.600.620.640.660.690.710.730.750.770.790.810.830.850.880.900.920.940.960.981.00--
0.550.660.680.700.720.750.770.790.820.840.860.890.910.930.950.981.00----------
0.500.720.750.770.800.820.850.870.900.920.950.971.00------------------
0.450.800.830.860.890.910.940.971.00--------------------------
0.400.900.930.961.00----------------------------------
0.35------------------------------------------
0.30------------------------------------------
0.25------------------------------------------
0.20------------------------------------------
0.15------------------------------------------
0.10------------------------------------------
0.05------------------------------------------


Second-by-second energy demands
This comma-delimited data can be copied and pasted into a text file, then imported to a spreadsheet.
To select it all, click in the field and type ctrl-A (PC) or command-A (Mac).
The modeling methodology document explains how these figures were computed.

Consistency checks:

Energy balance: -4.65661287307739e-10 (-5.70386656096203e-15 %)
Energy balance successful.

Inertia balance check:
Positive inertia energy: 4868024.88 J
Removed by aerodynamic drag: 588272.25 J
Removed by rolling resistance: 905967.82 J
Removed by brakes: 3373784.81 J
Balance: -1.28056854009628e-08 (-2.63057106657519e-13 %)
Inertia balance successful.

Mode A (Accel)Mode B (Decel, Cruise, Idle)Mode C (Braked Decel)SumError
Aerodynamic Drag:892267.06826326.05327182.972045776.082.09547579288483e-09
Rolling Resistance1275459.09814500.36654437.952744397.402.79396772384644e-09
Braking0.000.003373784.813373784.810
Inertia4868024.88-512619.15-4355405.73-0.00-0.00


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