# Engine Benchmark Cummins ISB 6.7 and Navistar N13

Southwest Research Institute 11 - December - 2014

# Outline

• Medium Duty

– HIL to Engine Conversion

– Powertrain & Engine Correlation

– Engine Fuel Mapping  Ramped Modal vs. Steady State



# – Engine Benchmarking 

# • Heavy Duty

– Engine Fuel Mapping

– Engine Benchmarking

– Engine to HIL Conversion
2 11 - Dec - 2014

# Medium Duty HIL to Engine

Conversion & Correlation

3 11 - Dec - 2014

# MD Engine Test Setup

• Cummins ISB10 6.7 I6

– Tested 300 hp and 240 hp ratings 

# • Taken out of an F650 flat bed tow truck • HP common rail • Single VGT turbo 

# • Cooled EGR • DOC/DPF/SCR • 2010 Emission Compliant
4 11 - Dec - 2014

# HIL to Conventional Engine Testing Setup

• Conversion to engine dynamometer configuration

– Removed transmission



## – Disabled “Max Engine Speed without VSS” via Cummins Insite Software

– Connected transmission electrical connectors to disable “Powertrain Protection Status”
 Needed a vehicle speed sensor 5 11 - Dec - 2014

# ISB Torque and Power Map ISB 6.7 CM2250 rating: Peak Power: 224 kW @ 2600 rpm Peak Torque: 895 N - m @ 1600 rpm SwRI Measured:

6 0 20 40 60 80 100 120 140 160 180 200 220 240

0 100 200 300 400 500 600 700 800 900 1000

750 1000 1250 1500 1750 2000 2250 2500 2750 Power [kW] Torque [N - m]



## Engine Speed [rpm] 

## F650 Cummins ISB 224 kW Rating

Torque N - m Power kW

11 - Dec - 2014

# Correlation With Powertrain Setup

• Select points from previous powertrain SET were used to correlate engine performance under steady - state conditions.

– Engine speed and pedal position values matched

– Both setups resulted in comparable engine and emission performances  Engine setup does not appear to be limited by other software limitations i.e. de - rate, fuel economy modes, etc.



## – Engine curb idle torque was also determined by matching fuel consumption 7 1 2 3 4 5 6 7 Fuel Flow [kg/hr]

Modes

CITT Fuel Matching: 80 N - m

1 2 3 4 5 6 7 EO NOx Sensor [ppm]

Modes 1 2 3 4 5 6 7 Output Torque [N - m]

Modes Engine Powertrain Engine_Est

Transmission Losses

11 - Dec - 2014

# Medium Duty Engine Fuel

Mapping & Benchmarking

8 11 - Dec - 2014

# ISB Engine Fuel Mapping

• Speed [rpm]: 750, 900, 1050, 1200, 1350, 1500, 1650, 1800,

1950, 2100, 2250, 2400, 2550, and 2650 • Load [%]: 100, 90, 75, 60, 50, 35, 25, 10, 5, and 0

9

0 200 400 600 800

750 950 1150 1350 1550 1750 1950 2150 2350 2550 2750 Engine Torque [N - m]



## Engine Speed [RPM]



# ISB 300 hp Fuel Mapping Points

11 - Dec - 2014

# ISB Engine Fuel Mapping

• Modern engines have layers of sophisticated controls which change engine fueling subject to different operating conditions

– Fuel economy optimization

– Volumetric efficiency compensation

– Combustion phasing

– Thermal management

– Soot control

– Rail pressure dynamic

– DPF regeneration

– Altitude

– And many more optimization strategies

10 11 - Dec - 2014

# ISB Engine Fuel Mapping

• Two methods were explored while mapping fuel rates

– Traditional steady state fuel mapping (~5 min or longer at each mode)

– Ramp modal fuel mapping (20 sec ramps and 60 sec at each mode before sampling)

11 

## Ramp Modal Fuel Mapping Example:

11 - Dec - 2014

# ISB Engine Fuel Mapping

• Ramp Modal

12 

# • Steady - State

Fueling Differences at light loads 11 - Dec - 2014

# ISB Fuel Mapping

13 

# • Ramp modal – Steady - State Fueling :

Fueling Differences at light loads



# • The two methods yield nearly identical fueling rates, except at light loads when exhaust temp falls below 200 degC. 100 150 200 250 300 350 400 450 500

0 2 4 6 8 10 12 14

5000 5250 5500 5750 6000 Exhaust Temp [degC] Fuel Flow [kg/hr]



## Time [sec] Fuel Flow kg / hr Exhaust T degC

Thermal Mgt Starts Fueling reduces as exhaust t emp e xceeds 250 degC

11 - Dec - 2014

# ISB Motoring Curves

• Engine pre - conditioning greatly impacts motoring results

14 Torque [N - m]



## Engine Speed [RPM] Torque N - m (SS) Torque N - m (Ramp1) Torque N - m (Ramp2) Torque N - m (Ramp3)

Measured friction is lower due to a change in air flow strategy Intake Air Flow [kg/hr]



## Engine Speed [RPM] Torque N - m (SS) Torque N - m (Ramp1) Torque N - m (Ramp2) Torque N - m (Ramp3) 10 min Rated – 2 nd Ramp 10 min Rated – 1 st Ramp

11 - Dec - 2014

# ISB Benchmark: FTP, SET, WHTC & ARB

• SwRI finished CO 2 

# /fuel measurement over the FTP, WHTC, and ARB cycles on the 300 hp rating (cold - start and hot starts) • Cycle results [g/kW - hr] :

• BSCO 2 

# COV ~ 0.5%
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# Navistar N13 Engine Fuel

Mapping & Benchmarking

16 11 - Dec - 2014

# Navistar N13 Engine Setup

17 

# • Navistar N13

– Tested 475hp, 450hp, and 410 hp ratings 

# • Primarily class 8 

# commercial truck • HP common rail • Inter - stage cooled 

# sequential turbo • Cooled EGR • DOC/DPF/SCR • 2010 Emission Compliant
11 - Dec - 2014

# Navistar N13 Engine Setup

18 11 - Dec - 2014

# N13 Fuel Mapping

19 

# • Ramp modal fuel mapping only, based on medium duty results

11 - Dec - 2014

# N13 Benchmark: FTP, SET, WHTC & ARB

• SwRI conducted transient cycles to be used for later studies

– FTP, WHTC, ARB, FTP

20 11 - Dec - 2014

# Navistar N13 HIL Configuration

21



# • Installed automated manual transmission • Collaborative ongoing effort to complete powertrain benchmarking 11 - Dec - 2014

# Summary

• SwRI converted & correlated medium duty powertrain to engine configuration

– Completed two methods of engine fuel mapping, 

# and engine benchmarking on FTP, ARB, WHTC, and SET cycles 

# • SwRI completed engine benchmarking of 

# heavy duty Navistar N13 • Continuing with powertrain benchmarking

22 11 - Dec - 2014

# Questions?

23 11 - Dec - 2014