Prime Time Evaluation for Engine Lubrication System
Model based approach by using GT-SUITE
November 06, 2017
Shuran ChengFCA US LLC
GT’17 - Plymouth, MI
©2017 FCA US LLC
Yifan ZhouDEP
Wei TaoFCA US LLC
Meng LiDEP
Powertrain Virtual Engineering
2©2017 FCA US LLCGT’17 - Prime Time Evaluation for Lubrication System November 06, 2017
Objective
Develop oil circuit analytical models to
• Predict time for the oil to reach target component
• Optimize lubrication system to reduce the prime time
Prime Time = pump fill time + circuit fill time
Time for the oil to flow from pickup tube to the
lubrication system.
pump fill time
circuit fill time
Oil Circuit of Pentastar Upgrade
3©2017 FCA US LLCGT’17 - Prime Time Evaluation for Lubrication System November 06, 2017
Critical Input Parameters
• Design parameters:
1. Oil circuit geometry (length, width……)
2. Bearing geometry (diameter, clearance, groove……)
3. Oil pump design
• Hydraulic component pressure vs flow rate curve
1. Cam Phasers
2. Piston cooling jets (PCJ)
3. Hydraulic lash adjusters (HLA)…
• Cylinder pressure
• Initial condition
1. Temperature
2. Composition0.0
0.2
0.4
0.6
0.8
1.0
0 200 400 600 800N
orm
ali
ze
d P
res
su
re
Crank Angle [degree]
Cylinder Pressure
4©2017 FCA US LLCGT’17 - Prime Time Evaluation for Lubrication System November 06, 2017
Simulation Assumptions
• Oil Type: 5W30
• Constant oil temperature: -20C
• Standard predictive components are used for priming analysis
• Initial composition: 100% air
• Nominal bearing clearances
• Time vs engine speed profile Engin
e S
pee
d
Time
Engine Speed
5©2017 FCA US LLCGT’17 - Prime Time Evaluation for Lubrication System November 06, 2017
Model Building from CAD
GT-SPACECLAIM GEM3D GT-ISE
• Import CAD model into GT-SPACECLAIM and extract fluid core
• Export fluid core to GEM3D and create 1D model for GT-ISE
• Complete model setup and run from GT-ISE
All three images in this slide:
Courtesy Gamma Technologies;
used with permission
6©2017 FCA US LLCGT’17 - Prime Time Evaluation for Lubrication System November 06, 2017
Engine Lubrication Model
Oil Circuit Model
Oil pump (vane)
Note: Adapted from Gama Technologies demo models.
Cranktrain
7©2017 FCA US LLCGT’17 - Prime Time Evaluation for Lubrication System November 06, 2017
A detailed oil pump model is built and used in this simulation
• Build the pump model from a CAD model in GEM3D;
• Vanes, rotor and control valve are included;
• The model can predict the flow rate of the pump;
• Aeration effect can be considered.
Oil Pump Model
Courtesy Gamma Technologies;
used with permission
8©2017 FCA US LLCGT’17 - Prime Time Evaluation for Lubrication System November 06, 2017
Prediction Correlation
Pre
ssure
Time
Prime Time CorrelationPressure at Main Oil gallery @-20C
GT Simulation
Test
Simulation correlates well with the test data.
9©2017 FCA US LLCGT’17 - Prime Time Evaluation for Lubrication System November 06, 2017
0
20
40
60
80
100
Vo
lum
e F
ract
ion
Time
Air Volume Fraction @Pipe in Cylinder Head
Baseline Design
Design Proposal 1
Design Proposal 2
Prime Time Change due to Different Designs
Different design proposals will change the time
for the oil to fill the system
Optimized Design
Courtesy Gamma Technologies;
used with permission
10©2017 FCA US LLCGT’17 - Prime Time Evaluation for Lubrication System November 06, 2017
Prime Time Change due to Different Temperatures
Different temperatures will change the time for
the oil to reach the whole system
0
20
40
60
80
100
Vo
lum
e F
ract
ion
Time
Air Volume Fraction @Pipe in Cylinder Head
-20C
25C
Courtesy Gamma Technologies;
used with permission
11©2017 FCA US LLCGT’17 - Prime Time Evaluation for Lubrication System November 06, 2017
100% Air
100% Oil
Priming Results –Animation
▪ Animation to visualize total air volume fraction and oil
volume fraction in the system.
Note: Adapted from Gama Technologies demo models.
12©2017 FCA US LLCGT’17 - Prime Time Evaluation for Lubrication System November 06, 2017
Priming Results –Animation
Pressure
(abs. bar)
▪ Animation to visualize pressure distribution in the system.
Note: Adapted from Gama Technologies demo models.
13©2017 FCA US LLCGT’17 - Prime Time Evaluation for Lubrication System November 06, 2017
Conclusions
▪ GT-SUITE is capable of predicting the prime time of
engine lubrication system.
▪ GT-SUITE simulation result correlates well with the dyno
test.
▪ The model can be used to evaluate different designs in
order to reduce prime time.
14©2017 FCA US LLCGT’17 - Prime Time Evaluation for Lubrication System November 06, 2017
Q & A