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March 2018
ePCC System Waukesha VHP Engine Upgrade Packages
Division Engines
6/21/2018 2
Lean Burn Combustion
The Challenge
A leaner mixture is more difficult to ignite and has typically a slower
flame propagation
The Obvious Idea
Improved ignition (key issue)
The solution
Pre Combustion Chamber
Order of magnitude higher ignition energy
BUT, it requires precise air/fuel ratio control to ensure stable main
chamber combustion
6/21/2018 3
PCC Ignition
PCC – Pre Combustion Chamber
Small cavity providing an easy to ignite environment (stoichiometric)
Order of magnitude higher ignition energy compared to open chamber
ignition
State of the Art
Check valves
Problems:
Inconsistent fueling
Frequently clogged / quit working
Varying Air/Fuel ratio
Too rich Air/Fuel ratio during startup
Fuel slip
6/21/2018 4
Combustion Stability at Lean Mixtures
Ignition (Pre Chamber)
Evaluation of PCC performance – MCC pressure and PCC ion sense
170 180 190 200 210 220 230
200
250
300
350
400
450
500
550
600
650
700
Crank angle, deg ABDC
Cylin
de
r p
ressu
re, P
SI
Pressure
Avg pressure
PCC A
PCC B
170 180 190 200 210 220 230
200
250
300
350
400
450
500
550
600
650
700
Crank angle, deg ABDC
Cylin
de
r p
ressu
re, P
SI
Pressure
Avg pressure
PCC A
PCC B
Slow and late main
chamber combustion due
to delayed PCC firing
Stable main chamber
combustion due to
perfect PCC firing
6/21/2018 5
Combustion Stability with ePCC
0 5 10 15 20 25 302.5
3
3.5
4
4.5
5
5.5
6x 10
6
loc PP, colVar: IonA.caVmax-IonB.caVmax
PP
0.0E+000
5.0E+000
1.0E+001
1.5E+001
2.0E+001
2.5E+001
3.0E+001
3.5E+001
4.0E+001
4.5E+001
5.0E+001
Peak pressure location
Peak p
ressure
Stable combustion
Poor combustion due
to late or missing
ignition of one or both
pre chambers (Check
valve)
Perc
enta
ge o
f po
or
com
bustion c
ycle
s
Check valve ePCC0
1
2
3
4
Avg fra
ction o
f cycle
s p
er
run
Slow burning
PCC not firing
PCC late
Sum of both
ePCC tested at
even leaner
combustion
Perc
enta
ge o
f po
or
com
bustion c
ycle
s
Check valve ePCC0
1
2
3
4
Avg fra
ction o
f cycle
s p
er
run
Slow burning
PCC not firing
PCC late
Sum of both
ePCC tested at
even leaner
combustion
Check Valve Performance Check Valve vs.
Electronic Valve
The real solution is a pre combustion chamber with
electronic fuel injection
ePCC
6/21/2018 6
Implementation on High-Speed Engines
Results Waukesha 7042GL
Bulk engine PCC fueling optimization (same pulse width for all cylinders,
individual adjustment possible)
Improvements with ePCC could be demonstrated compared to new and
optimal adjusted check valve fueling
CV PP vs TER, engine average
1000 rpm, 100% torque
0.00
1.00
2.00
3.00
4.00
5.00
6.00
0.500 0.510 0.520 0.530 0.540 0.550 0.560 0.570 0.580
TER
CV
PP
Check valve
ePCC
Increasing with check valve runtime
Leaner AFR
Co
mb
us
tio
n
sta
ble
u
ns
tab
le
6/21/2018 7
ePCC Waukesha 7042GL Package
Field and Lab Test Results
Improved combustion stability at rated
operating conditions as well as
reduced hydrocarbons emission and
slightly improved fuel consumption
Achieved stable combustion down to
0.5g/bHp-hr NOx
6/21/2018 8
ePCC Waukesha 7042GL Package
Field Installation
6/21/2018 9
ePCC Installation Experience
Slow Speed Engines
100+ engines are running successfully in the field
Very positive customer feedback due to outstanding performance
First installation in operation for more than 10 years
High Speed Gas Engines
20+ installations on Superior 825 and Waukesha VHP engines
Combustion performance improvements are identical to large bore
engine results
First installation in operation since Nov 2011
6/21/2018 10
ePCC Highspeed Package – Summary
The Need
Most lean burn engines require pre combustion chambers for igniting the lean
mixture. The fueling is controlled via check valves, which perform poorly:
Frequently clogged / quit working
Inconsistent fueling; varying Air/Fuel ratio
Too rich Air/Fuel ratio during startup; fuel slip
Root cause #1 for combustion issues
The Solution
Electronically controlled pre chamber fuel valve – ePCC
No maintenance issues
Precise and consistent fueling (each cycle)
Stable combustion even at very lean mixtures
Improved startup, smooth and efficient idling
Small Fuel Saving’s
Pre Chamber
Check Valve
Controller
ePCC
We are Engine.