Improving engine Gino Rizzetto Performance through ...unina.stidue.net/Universita' di Trieste/Ingegneria Industriale e... · Performance through innovation and design WÄRTSILÄ Italia

1 © Wärtsilä G. Rizzetto

Improving engine Performance through innovation and design

WÄRTSILÄ Italia S.p.a.

Gino RizzettoEngine Performance Manager, Testing & Performance


WÄRTSILÄ in brief

New emissions requirements impact on fuel consumption and

smoke

Flexible valve timing: how to combine low NOx, low smoke

with high efficiency engine

High pressure TC (single stage new generation and two stage

TC) to lower NOx emission keeping high engine efficiency

Combustion process optimization to improve NOx emission

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WÄRTSILÄ in brief


smoke






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WÄRTSILÄ in brief: our offering

EnginesPropulsors

Ship Powersystems

O&M

PowerPlants

Competitors’engines

OEMservices

Shipservices

WE ARE A LEADING SUPPLIER OF FLEXIBLE POWER PLANTS FOR THE

DECENTRALIZED POWER GENERATION MARKET

Merchant Offshore Cruiseand Ferry Navy Special

Vessels

OUR OFFERING COVERS ALL KEY SHIPPING SEGMENTS


WÄRTSILÄ in brief: network services

Workshop

Product Company

Network

Trieste, ItalyW26, W38, W46,

W46F, W50DF, W64

Bermeo, SpainW34SG, W50DF

Winterthur, Switzerland2-stroke: RT-flex, RTA

Vaasa, FinlandW20; W32/32DF/34SG,

Ecotech

Havant, UK; Slough, UK

Face Seals,Synthetic Bearings Toyama, Japan

Rubber Seals &Bearings

Stord, NorwayElectrical &

Automation systems

Trondheim, NorwayFrequency converters

Rubbestadneset, Norway

CPP, Gears Espoo, FinlandFuel cells, Ecotech

Drunen, The NetherlandsCPP, FPP, Thrusters

Turku, FinlandEcotech


WÄRTSILÄ in brief: Global R&D and T&P locations

- Define and validate new concepts- Provide tech. information on products- Develop expertise


WÄRTSILÄ in brief


smoke






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New emissions requirements impact on fuel consumption and smoke

Wärtsilä engine portfolio

…. solutions for marine and land based power generation…. from 0.8 MW to 80 MW…. from 61 rpm to 1200 rpm …. (Turbocharged) Gas, Diesel and Dual Fuel operation

4 - stroke 2 - stroke0 5 10 15 20 25

Wärtsilä 64

Wärtsilä 46F

Wärtsilä 38Wärtsilä 32

Wärtsilä Vasa32Wärtsilä 26Wärtsilä 20

Wärtsilä 34SG-BWärtsilä 34SG

Gas and Dual fuel engines

Diesel engines

(MW)

SG

Wärtsilä 46

0 5 10 15 20 25

Wärtsilä 64

Wärtsilä 46F

Wärtsilä 38Wärtsilä 32

Wärtsilä Vasa32Wärtsilä 26Wärtsilä 20

Wärtsilä 34SG-BWärtsilä 34SG


Diesel engines

(MW)

SG

Wärtsilä 46

Wärtsilä 46GDWärtsilä 32LNGD Dual fuel engines

Wärtsilä 50DFWärtsilä 32DF

GD

DF

Wärtsilä 46GDWärtsilä 32LNGD Dual fuel engines

Wärtsilä 50DFWärtsilä 32DF

GD

DF

Wärtsilä 50SG


4s Wärtsiläengines

0

2

4

6

8

10

12

14

16

18

0 100 200 300 400 500 600 700 800 900 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 2100

Rated engine speed (rpm)

NO

x (g

/kW

h)



Wärtsilä engines

Tier I - 130 kW - New ships 2000 Tier II - 130 kW - New ships 2011

Revised Marpol Annex VI (9.10.2008)

Tier III - 130 kW - New ships 2016 in designated areas

2011 Tier2 limit14.4 – 9.0 g/kWh ISO NOx

2000 Tier1 limit17.0 – 11.3 g/kWh ISO NOx

2016 Tier3 limit3.4 – 2.3 g/kWh ISO NOxOnly designated area (ECA)(Baltic Seat, North Sea, Costal Water)

-20%

-80%

Cycle\Load 100 75 50 25 10E2/E3 29% 55% 11% 5% 0%D2 11% 40% 32% 16% 2%

NOx weight factor

Cycle NOx

Tier 3 load point limit < 1.5 NOx cycle average5.1 – 3.4 g/kWh ISO NOx

NOx emission control drives engine performance

development





Severe NOx emission limits will strongly penalize SFOC and smoke.

New technologies development to find a compromise between these

contesting objectives/constraints.

Players to reach specific emission levels:

High Exhaust Gas temp. according to the fuel sulphur content for SCR use

To limit the SCR UREA consumption NOxmust be reduced at the engine stage

Fuel quality to avoid scrubber or particulates filter



Tier2 is the NOx level we are currently facing by means of:

a. Low NOx combustion tuning

High compression ratio & retarded inj. timing (SOC @ TDC)

Triangular injection rate shape

Optimized injection pressure in the 50% - 75% load range (CR engines)

Combustion space optimization (piston top and injector geometry)

b. Turbo Charging

Remarkable Miller timing

Valve timing flexibility

Lower receiver temperature

• Early inlet valve closure:

• Shorter compression stroke

• Lower charge temperature inside cylinder

89

1011121314151617181920

175 180 185 190 195

BSFC, ISO corr 42.7MJ/kg

NO

x, IS

O c

orr [

g/kW

h]

15

13.5

12

235 230 220 210

FIRING PRESSURE av. cock

SOI

85% timing swing 568 rpm – NOx-SFOC

16.5

3g/

kWh

4 g/kWh

eps 16.2

eps 16.8

+ 5 - 5 - 15+ 10



Increased compression ratio and retarded injection timing+ Improved SFOC/NOx trade off

– Worse Pmax/SFOC trade off

• NOx reduction

• limited penalty in SFOC

• at constant firing pressure

– Retarded timing for NOx emission deteriorates the Smoke Emission (AVL FSN)

smok

e [F

SN

]

NOx [g/kW]

Smoke vs NOx Emission

SOI swing - 10% load



Wärtsilä 8L46F-TP PROTO3, 1200kW/cyl,

0 20 40 60 80 100

NOx reduction potential [%]

IMO3IMO2

High pressure TC sys. (2-stage) Low NOx combustion tuning EGR system Charge air humidification Water Fuel Emulsion Direct Water Injection NOR system Gas and Dual Fuel tech.

Com

bina

tion

need

ed

to m

eet T

ier3

targ

et



NOR (Nitrogen Oxide Reducer)

2-stage charging system + Wetpac

2-stage charging system + EGR

Dual Fuel engine / Fuel conversion + DF engine

EGR (internal/external) + Wetpac

2-stage NOx opt. / Fuel optimized + SCR (NOR)

Exhaust scrubber + above combinations (HFO operation)

Example of possible combinations (4-stroke)

HOW TO GET CLOSER TO TIER3 ?



2-stage charging system + EGR

Smok

e em

issi

on [F

SN]

engine load [%]

2stage + EGR

2stage

NO

x em

issi

on [g

/kW

h]

engine load [%]

2stage + EGR

2stage

IMO3

SFO

C [g

/kW

h]

engine load [%]

2stage + EGR

2stage

Exhaust gas recirculation provides big step on NOx reduction, but SFOC and smoke deteriorations have to be paidThe driving goal for Tier3 is the best compromise between:

CAPEX vs OPEXReliabilityComplexity of the solution

20 40 60 80 1000 20 40 60 80 1000

20 40 60 80 1000


CO2

NOx

SOx

Particulates

Dual-Fuel enginein gas mode

Dieselengine

0

10

20

30

40

50

60

70

80

90

100

Emissionvalues [%]


The facility to reach Tier3 has to pay:• On board gas system • Reformer technology• Liquid mode

efficiency

Dual Fuel engine / Fuel conversion + DF engine

Development drivers:• Output and efficiency • Liquid mode

performance• Low methane number

operation• Methane slip


IMO TIER 2 (2009)Efficiency change to TIER 1: -1to +1%Output change to TIER 1: 0 to -4%

IMO TIER 2 (2012)Efficiency change to TIER1; +1,5 to +3,5 %Output change to TIER 1: 0 % to +10%

IMO TIER 2 (2009) -30% NOxEfficiency change to TIER1 +3%Output change to TIER 1: 0 %

IMO TIER 3, based on 2-stage technologyEfficiency change from TIER 2: 0 to -5%Output change from TIER 2: 0 to -5 %

IMO TIER 3, after treatmentEfficiency change; +0 to 3%Output change: +0 to 15 %

IMO TIER 3, gas and gas conversionEfficiency change from TIER 2: 0 to +2 % Output change from TIER 2: 0 to -10 %

2010 2012 2014 2016

IMO

Tie

r 2Pr

oduc

t de

velo

pmen

t IM

O T

ier 3

Prod

uct

deve

lopm

ent

2008

IMO Tier II in force IMO Tier III in force


Max SFOC penalty 1%Max output penalty 4%

Improved Tier II concept, higher output / efficiency

High pressure charging system

Focus on engine and aftertreatment integration

Focus on technical feasibility and OPEX

Focus on: - Liquid mode eff. - Gas mode output


WÄRTSILÄ in brief


smoke






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Pressure ratio - NOx trade off

456789

10

<<<<< Earlier IVC

PIC

020406080100120

NOx

%

Flexible valve timing: how to combine low NOx, low smoke with high efficiency engine

VIC Variable Inlet Closure has been introduced

VIC allows to control timing for inlet valve closure

Why:

To lower NOx emission, early IVC is used at high

loads

VIC to enhance low load…

Smoke and thermal load and

Load acceptance

300,0 320,0 340,0 360,0 380,0 400,0 420,0 440,0 460,0 480,0 500,0 520,0 540,0°CA

Reference

TDC BDC

300,0 320,0 340,0 360,0 380,0 400,0 420,0 440,0 460,0 480,0 500,0 520,0 540,0

TDC BDC

VIC OFF

VIC ON

CA deg

Inlet valve lift

VIC detail VIC effect

0 10 20 30 40 50 60 70 80 90 100 110

Sm

oke

emis

sion

(FS

N)

Engine Load (%)

Wärtsilä 8L46F-TP PROTO3, 1200kW/cyl, 600rpm TPL76-C33 CV33CT60CD06CA13 TV11TT40TF15TN05TA14

eps 16.8 - DPPpiston -12x0.72x165°- 286 - symm scav - Jan. 10 - CS - VICVIC off


Flexible valve timing: how to combine low NOx, low smoke with high efficiency engine

VIC to allow late inlet valve closure at part load:

Smoke benefit during steady state operation

Smoke benefit during transient operation

Improved load pick-up with reduced

speed drop

7L32C without VIC. Load ramp from 0% up to 100% in 10s

7L32C with VIC. Load ramp from 0% up to 100% in 10s

Time [s]

spee

d [rp

m]

Improved speed recovery with VIC

VIC on


WÄRTSILÄ in brief


smoke






List of content


High pressure TC to lower NOx emission keeping high engine efficiency: Diesel

New TC system (KBB ST27, ABB A100M, Napier 8)• Higher TC efficiency +3%• Pressure ratio up to 5.8• Further increased Miller timing• VIC rolled out on all portfolio

2-stage system SFOC optimized • TC system efficiency 75%• Pressure ratio > 8.0• Optimized “extreme Miller” timing• Multi steps VIC

Up to 5% lower SFOC AND 10% ..15% higher output

Up to 2% lower SFOC OR10%...15% higher output

Compared to the current supercharging status, higher boost pressure availability at

higher TC efficiency level would provide:

The extreme Miller drawbacks will be faced by means of the variable valve timing:

• Difficult engine start-up and low load running

• Increased smoke emissions

• Worse load pick-up

Charge air receiver

AC

HP turbine

HP compr.

LP turbine

LP compressor IC

nTC LPt0 p0t1 LP

p1 LP p2 LP

t2 LP

p1 HP

t1 HP

p2 HP

t2 HP

p3

nTC HP

t3

p5 HP p5 LP

t5 HP

t5 LP

p6 LP

t6 LP t4

NO

x [g

/kW

h]

SFOC [g/kWh]

6L20CR 2stage - eps 16 - 27.3 bar bmep @ 1000 rpm

Miller 33 IMO Tier2

Miller 96

Miller 83

1 g/

kWh

5 g/kWh-15

-10

-5

0

5

0 200 400 600 800 1000 1200 1400

delta

BSF

C [

g/kW

h]

power output [kW/cyl]

W46F 2stage 600rpm - expectation at IMO tier2

Reference

2-stage


High pressure TC to lower NOx emission keeping high engine efficiency: Diesel

2stage TC IMO2:Expected performance on variable SOI engine:

Power output 1200 1320kW/cyl (+10%)

SFOC reduction on E2 cycle ~ -10g/kWh

2stage TC towards IMO3:50% NOx reduction at constant SFOC:

1- stage reference

-50%

IMO2 with 2 stage Towards IMO3 with 2 stage


CO2

NOx

SOx

Particulates

Dual-Fuel enginein gas mode

Dieselengine

0

10

20

30

40

50

60

70

80

90

100

Emissionvalues [%]

High pressure TC to lower NOx emission keeping high engine efficiency: Gas

Development drivers:

Limiting factors Solutions

Output and efficiency

• Knock margin• Firing pressure• Available boost level

• Strong Miller timing• New hardware platform• New TC generation

Liquid mode performance

• Low comp. ratio• High NOx emission

• Strong Miller timing & higher compression ratio• New TC generation

Low MN operation

• Knock margin • Strong Miller timing• New TC generation

High boost pressure system is a key factor as well in the Gas engine development

High Pressure TC on DF engine


WÄRTSILÄ in brief


smoke






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Baseline pistonSOI ±2°CA

NOx g/kWhSF

OC

g/k

Wh

-3/-4 g/kWh

Tier II area

NOx BSFC, ISO corrected

89

1011121314151617181920

175 180 185 190ISO SFOC 42.7 MJ/kg [g/kWh]

ISO

NO

x g/

kWh

eps 16.8 - DPPpiston -12x0.72x165° - 85%

eps 16.8 - DPPpiston -12x0.72x163° - 85%

eps 16.8 - DPPpiston -12x0.72x161° - 85%

eps 16.8 - DPPpiston -12x0.72x159° - 85%

Wärtsilä 8L46F-TP proto3, 1200kW/cyl, 600rpm

NOx ISO corrected - p_max normalised

89

1011121314151617181920

180 190 200 210 220 230 240 250p_max [bar]

ISO

NO

x g/

kWh

eps 16.8 - DPPpiston -12x0.72x165° - 85%

eps 16.8 - DPPpiston -12x0.72x163° - 85%

eps 16.8 - DPPpiston -12x0.72x161° - 85%

eps 16.8 - DPPpiston -12x0.72x159° - 85%

Wärtsilä 8L46F-TP proto3, 1200kW/cyl, 600rpm

SFOC > target

Non allowed area

Spray angle swing: influence on SFOC/NOx at constant firing pressure

• At constant firing pressure 165° angle allows the best SFOC or…• At constant NOx emission 165° angle allows the lowest SFOC and p_max

165° 163°

161°

159°

• CFD+engine verification for optimized comb. chamber

• Piston top shape & fuel spray pattern

• Eps, SFOC – NOx, SFOC – p_max, exhaust temp.,

piston heat flux, soot are considered

1g/kWh

• Injector geometry optimization (CFD and experimental) is a part of the process

27 © Wärtsilä Overview

People in Wärtsilä and R&D

• People are important in Wärtsilä: we need people

• University can be a partner

• Wärtsilä offer:

• Summer Job 3 months (fee and accommodation)

• Master Thesis 6 months (fee and accommodation)

• Post Laurea internship 6 months (fee and accommodation)

• Phd/cooperation with University case by case agreement

Research

Technology development

Productdevelopment


”Every third ship you see is powered by us”

”Every second ship you see is serviced by us”

“One per cent of Global energy is produced by Wärtsilä”

“We are the doers”

“We make things happen”

“We are the Engine of Industry”

Thank you for your attention !

Documents

Improving engine Gino Rizzetto Performance through ...unina.stidue.net/Universita' di Trieste/Ingegneria Industriale e... · Performance through innovation and design WÄRTSILÄ Italia