Oil Flow in Gasoline Engines

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Oil Flow in Gasoline Engines
Christopher Hammond, John Lindsay Smith, Moray
Stark, David Waddington Department of Chemistry
University of York Richard Gamble, Martin
Priest, Christopher Taylor School of Mechanical
Engineering University of Leeds Harold
Gillespie, Eiji Nagatomi, Ian Taylor Shell Global
Solutions (UK)
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Introduction
Aim To Predict Increase in Piston Friction with
Oil Degradation Chemical Model for Base Fluid
Oxidation Rheological Model for Increase in
Viscosity Tribological Model for Piston
Friction In This Talk Measure Fluid Flow in
Piston Ring Pack Comparison with Tribological
Model Chemical Model using Measured Flow
Parameters
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Engine Specification
Ricardo Hydra Fuel Injected Gasoline Single
Cylinder 0.5 litre Capacity 1500 rpm 50
Throttle External Sump (70 ºC) Camshaft
Lubricated Separately Shell XHVI 8.2 No
Additive Package
Lubricant Specification
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Extraction of Oil from Top Piston Ring
1/8 PTFE Tube
Sample Collection
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Piston Assembly
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Oil Flow in Engine
Small Volume Short Residence Time
Ring Pack
Flow Rate
Large Volume Long Residence Time
Sump
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Ring Pack Residence Time ?ringpack
1-e-1
?
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Ring Pack Residence Time 60 sec
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Ring Pack Residence Time Previous Work
S B Saville, F D Gainey, S D Cupples, M F Fox, D
J Picken, SAE Technical Paper, International
Fuels and Lubricants Meeting, Oct 10-13, 1988
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Oil Flow and Chemistry in Engine
High Temperature Small Volume Short Residence
Time
Ring Pack
Low Temperature Large Volume Long Residence Time
Sump
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Oxidation Chemistry
Hydrocarbon Base Fluid
Hydroperoxides
Infrared Spectroscopy of Carbonyl Group
Ketones
CarboxylicAcids
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Oxidation in Sump IR Spectrospcopy
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Oxidation in Ring Pack
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Oxidation in Ring Pack Previous Work
S B Saville, F D Gainey, S D Cupples, M F Fox, D
J Picken, SAE Technical Paper, International
Fuels and Lubricants Meeting, Oct 10-13, 1988
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Sump Residence Time and Oil Flow Rates
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Characterisation of Ricardo Hydra Engine
Ring Pack Residence Time 60 15
seconds Volume of Oil 0.30 0.08
cm3 Temperature 200 C Flow Rates Into
Ring Pack 0.32 0.02 cm3 min-1 Returning to
Sump 0.27 0.01 cm3 min-1 Loss From Ring
Pack 0.05 cm3 min-1 Sump Residence
Time 156 8 hours Volume 3
litres Temperature 70 C Conditions 1500
rpm, 50 Throttle
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Piston Assembly
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Comparison with Tribological Model
Ring Pack Experiment Theory Residence
Time 60 15 ?10 seconds Volume of Oil 0.30
0.08 ? 0.02 cm3 Flow Rates Into Ring
Pack 0.32 0.02 ? 0.17 cm3min-1 Returning to
Sump 0.27 0.01 ? 0.12 cm3min-1 Loss From Ring
Pack 0.05 ? 0.05 cm3min-1 Sump Residence
Time 156 8 ? 300 hours Conditions 1500 rpm,
50 Throttle
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Oxidation Chemistry
Hydrocarbon Base Fluid
Current Mechanism
Hydroperoxides
Ketones
Diketones
Hydroxyketones
CarboxylicAcids
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Two Reactor Simulation
Residence Time Volume Temperature Sump
156 hours 3 litre 70 C Ring
Pack 60 sec 0.27 cm3 200 C
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Conclusions
Measured Oil Flow in Gasoline Engine Modelled
Fluid Flow in Ring Pack Modelled Base Fluid
Oxidation in Engine
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Abstract for STLE Houston 2002 ConferenceThe
Interaction of Lubricant Degradation and
Tribology in Automotive Gasoline Engines
Harold Gillespie, Eiji Nagatomi, Ian
Taylor, Shell Global Solutions, Shell Research
Ltd, PO Box 1, Chester, CH1 3SH, UK Richard
Gamble, Martin Priest, Christopher Taylor School
of Mechanical Engineering, University of Leeds,
Leeds, LS2 9JT, UK Christopher Hammond, John
Lindsay Smith, Moray Stark, David
Waddington Department of Chemistry, University of
York, York YO10 5DD, UK This work aims is to
develop a good understanding of lubricant base
fluid degradation in automotive gasoline engines
and how this affects engine tribology. Therefore
an integrated model has been developed that
describes both the lubricant flow within the
piston assembly and the chemical degradation of
the lubricant. Experiments with a Ricardo Hydra
gasoline engine have been performed using only a
hydrocarbon base fluid as lubricant, with no
additive package. Oil extraction from the ring
pack has allowed the residence time of oil in the
ring pack and the flow rate of oil from the sump
to the ring pack to be determined these are
compared with oil transport models. The rate of
oxidation of the base fluid has been determined
by FTIR spectroscopy the rate of base fluid
oxidation compares well with simulations using a
chemical model based on detailed free radical
chemistry. Biography The author is a research
chemist with a background in studying chemical
kinetics. Previous topics of investigation have
been in the field of hydrocarbon combustion and
process development in chemical engineering. This
background is now being used to study the
breakdown of lubricants in gasoline engines.