C346MCA DV5F Roar Noise Issue: CAE Study
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Fuel System Noise Reduction CAE Study using GT-Suite Dipl.-Ing. Xiaofeng Chen 20 th GT-Conference Dr.-Ing. Caroline Born Frankfurt, 20 th October PTi Fuel System, Ford of Europe
Transcript of C346MCA DV5F Roar Noise Issue: CAE Study
Fuel System Noise Reduction CAE Study using GT-Suite
Dipl.-Ing. Xiaofeng Chen 20th GT-Conference Dr.-Ing. Caroline Born Frankfurt, 20th October PTi Fuel System, Ford of Europe
Fuel Tank Sloshing Fuel Pump Noise Valve Noise (e.g. Purge Valve) Fuel Line Roar Noise
2 PTi Fuel System - X.Chen, H.Dines, C.Born Ford Motor Company
Possible Noise Sources of the Fuel System
Roar Noise on fuel return line
The CAE Model Low Pressure (LP) Fuel System Modeling of High Pressure (HP) Fuel Pump
Natural frequency analysis
Results
Natural frequency of LP system Pressure, flow and effect CAE correlation with test
Summary
3 PTi Fuel System - X.Chen, H.Dines, C.Born Ford Motor Company
Fuel Line Roar Noise: CAE study using GT-Suite
Ford Motor Company Roar Noise Model CAE results Test
results Summary
What is roar noise? A distinctive vibrational noise audible in the vehicle interior. Frequency: Broadband Noise Typical RPM range: 1800 – 2500 rpm Running conditions: Neutral, 1st gear and 2nd gear run up / run
down
4 PTi Fuel System - X.Chen, H.Dines, C.Born
Roar Noise on Fuel Line
Baseline Condition
Interior noise Front Return line vibration Tank Return line vibration
Ford Motor Company - Confidential Roar Noise Model CAE results Test
results Summary
Ford Motor Company
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Vibration from clips excites the vehicle body structure which radiates noise into
the vehicle interior
4) Noise radiator
2) Response 2EO pulsation travels down the return line and interacts with low
pressure fuel line resonance due to pipe dimensions
Vibration transfers across the fuel line clips to the body
3) Transfer path 1) Excitation
2EO pulsation generated in the LP side of the FIP
Roar Noise – Transfer Path
PTi Fuel System - X.Chen, H.Dines, C.Born
Animation of pressure pulsation
NVH Countermeasures Rubber hose Damping by absorbing energy
Air Damper Damping by pumping effect of trapped air
Resonator 50mm Damping by flow expansion pressure and cavity Resonator 60mm Damping by flow expansion pressure and cavity All 4 variants of countermeasure and the baseline will be investigated with CAE and vehicle tests
Possible Countermeasure
6 PTi Fuel System - X.Chen, H.Dines, C.Born Ford Motor Company Roar Noise Model CAE results Test
results Summary
7 PTi Fuel System - X.Chen, H.Dines, C.Born
System layout and HP pump model
Plunger Lift (mm/°) Volume change of Cam (mm^3)
Modelling HP Pump:
1 in, 4 out (Cam Room)
Pulsation driven by volume
change of Cam Room due
to Plunger displacement
Roar Noise Model CAE results Test
results Summary
Ford Motor Company Roar Noise Model CAE results Test
results Summary 8 PTi Fuel System - X.Chen, H.Dines, C.Born
Entire CAE Model
Control Factors: P-feed P-tank T-fuel Threshold of
Overflow Valve Engine Speed Fuel Flow …
CAE results
9 PTi Fuel System - X.Chen, H.Dines, C.Born Ford Motor Company Roar Noise Model CAE results Test
results Summary
Natural frequencies of the LP hydraulic system
15 Hz /450rpm
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30 Hz /900rpm
60 Hz /1800rpm
50 Hz /1500rpm
Pump event is in 2nd engine order
Critical engine speeds
Air Damper
PTi Fuel System - X.Chen, H.Dines, C.Born Roar Noise Model CAE results Test
results Summary
11 PTi Fuel System - X.Chen, H.Dines, C.Born
1500rpm Pulsation is in 2nd engine order
Pressure pulsation: Worst to best Base>60mm>Rubber hose>Air Damper
Ford Motor Company
The ‘same’ back pressure in different designs
Oscillation is damped
Roar Noise Model CAE results Test
results Summary NVH-fixes
Calculated pressure after NVH fixes in different designs
12 PTi Fuel System - X.Chen, H.Dines, C.Born
1500rpm
Ford Motor Company Roar Noise Model CAE results Test
results Summary
Pressure response to volume change in Cam Room
Ford Motor Company
Pressure pulsation (animation)
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Air Damper
Air damper ‘isolates’ Pressure Pulsation
Roar Noise Model CAE results Test
results Summary
ANIMATION (Damper)
Pres
sure
(bar
)
HPP Tank
PTi Fuel System - X.Chen, H.Dines, C.Born
ANIMATION (Base)
CAE correlation with test
14 PTi Fuel System - X.Chen, H.Dines, C.Born Ford Motor Company Roar Noise Model CAE results Test
results Summary
Ford Motor Company 15 PTi Fuel System - X.Chen, H.Dines, C.Born
Baseline/800rpm
Roar Noise Model CAE results Test
results Summary
Pulsation is in 2nd engine order (26 Hz for 800rpm)
2 peaks in each period Oscillations are close(CAE/TEST) Lower P-mean in CAE
Gauge Pressure
Test Result: P-mean: 0.23 bar P-oscil.: 0.44 bar
CAE Result: P-mean: 0.05 bar P-oscil.: 0.39 bar
NVH-fixes
Ford Motor Company 16 PTi Fuel System - X.Chen, H.Dines, C.Born
Air Damper/1800 rpm
Test result: P-mean: 1.03 bar P-oscil.: 0.24 bar
P-mean: ~1 bar
P-mean: ~4 bar CAE
CAE
Pulsation is in 2nd engine order (60 Hz for 1800rpm)
Oscillations are close (CAE/TEST) Higher P-mean in CAE Minor P-loss in CAE and TEST Effective by damping oscillation
Air damper
CAE result: P-mean: 1.8 bar P-oscil.: 0.22 bar
P-before P-behind
Test
Summary Critical RPM: 1500 rpm 1800rpm / CAE confirmed by test
Pulsation is in 2nd engine order / CAE confirmed by test
The effect of NVH countermeasures: / CAE confirmed by test Air Damper > Rubber Hose > 60mm > Baseline
NVH countermeasures work by damping pressure oscillation (back pressure is the
same in different designs) / CAE confirmed by test Minor P-loss across air damper/same back pressure in different designs/ CAE
confirmed by test
General agreement with test and DETAILED information available in CAE
17 PTi Fuel System - X.Chen, H.Dines, C.Born Ford Motor Company Roar Noise Model CAE Results Test
Results Summary
Thank You
