Hinduja Tech Limited A Hinduja Group Company

Lubrication System Analysis and Oil Pump Power Consumption Reduction Author: Madhusudhan R

Co Author: Prasanth B

Contributor: Meenakshi Sundaram I

www.hindujatech.com

Contents Objective and overview Methodology GT-Suite 1D Simulation model Single cylinder analysis Component characteristics

Results Optimisation Summary 2

Objective and Overview Flow Distribution and Power Consumption

Product Development Time reduction

1D System Model in GT-Suite Improving System Reliability

Lubrication system layout

Competency Building

Work flow Single cylinder GT-SUITE model Full scale GT-SUITE model Validation with test results Optimisation of configuration Optimized lubrication system 3

Methodology Bearing load 1.Auto 2.User defined Pump 1.Pump flow 2.Pump positive displacement 3.Pump external gear 4.Pump 5.Detailed Pump model Flow 1.Geometry 2.Predictive method 3. Flow map Bearings 1. Predictive method 2. Mean value

Clearances 1.Constant 2.Non-constant

•Oil characteristics •Speed and Bearing load

•Layout of the system

Output

•Gallery dimension

•Gallery pressure

Lubrication system 1D MODEL GT-SUITE

•Component locations •Components

•Bearing performance •Flow distribution •Pump flow

Characteristic

•Power consumption

•Oil pump

•Oil filter

•Analysis

•Oil cooler

•Periodic analysis

•Piston cooling jet

•Explicit Solver

•HLA

Predicted vs Tested Results

Model Verification The GT-SUITE-model is validated against the

test bed results and found to have acceptable correlation with variation of less than 10%.

MOG pressure (bar)

4 3.5 3 2.5 2 1.5 1 0

1000

2000

3000

Speed (RPM) Test result GT - Simulation

4000 4

GT-SUITE 1D Model HLA Oil Rail

Cam bearing

Oil cooler and oil filter

Cranktrain

Oil Pump

Main bearing

Conrod bearing

PCN

Oil gallery 5

Single Cylinder Analysis Objective Groove Volume

Single cylinder model • Optimize bearing groove size

Oil hole angle & size

• To locate oil hole in bearing

Gallery diameter

• For optimal gallery pressure

Results Inputs and Considerations 1.

Single cylinder pressure profile

2.

Constant pump flow based on flow estimation

Outcome 1. Bearing geometry is finalized

Gallery pressure for different oil inlet hole location and diameter

6

Oil Pump Characteristics Pump type used is Gerotor pump The Oil pump sizing is done based on the initial flow estimation

Initial flow estimation is given a flow rate cushioning of 1.45 times of flow requirement for vapor loses, pump wear, hot idle condition etc. Physical model of the pump was tested and flow rates are input in GT-SUITE model Pump flow characteristics are imposed in the Lubrication model through “Pump” template.

Pump map is given for temperature values of 95 and 110˚C

7

Relief Valve Characteristics Relief Valve Characteristics

Relief valve was constructed as spring based 35

Pressure relief valve senses pump exit pressure

Relief valve is modeled through predictive method

Flow (lpm)

conventional type 30 25 20

Stiffness of Pressure relief valve is set as 2.95

15

N/mm

10

Physical model tested and input to GT-SUITE model as a ‘FlowMap’ template

5 0

0

200

400

600

800

Pressure (kPa)

Oil Properties Oil grade used is SAE 5W-30

Properties

Unit

Value

Kinematic viscosity @ 40˚C

cSt

65

Kinematic Viscosity @100˚C

cSt

11.2

Density @ 15˚C

Kg/m3

863

8

Oil filter & PCN Characteristics Oil cooler and oil filter are given are imposed in the GTSUITE model in the form of ‘PressureLossConn’ object The Oil filter are given as Pressure drop vs. Oil flow rate curves through ‘FlowPDropTable’.

• Piston cooling nozzle is separately made

as a predictive model

lubrication model as flow map. •The spring based cooling nozzle’s

stiffness was set to 0.597N/mm

2.5 2

Flow (lpm)

•Obtained flow rates are imposed in the

GT-SUITE – PCN Predictive model

PCN flow map

Piston Cooling Nozzle (PCN)

1.5 1 0.5 0 0

1

2

3

Pressure (bar)

4

5

9

Bearings Characteristics • Bearings are modeled through Predictive method • Bearings are assumed to be constant clearances

• Bearings are assumed to remain as circular geometry •

Cylinder pressure profiles calculated from GT-POWER are fed in lubrication model to calculate bearing loads

• Martin and modified martin equations are chosen for main and conrod bearings respectively Cylinder Pressure Profile Design inputs from single cylinder analysis • Based on single cylinder analysis the following data were finalized -Oil entry hole diameter of main bearing -Oil entry hole location -Groove depth and width

10

Results

Gallery pressure

Max gallery pressure was 502kPa

Oil film thickness

Gallery pressure fluctuation

Pressure fluctuation in oil gallery was