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