Wärtsilä Seminar

Presented byMed Seghair / BDM

Wärtsilä Finland Oy

Wärtsilä Seminar

International Standard ISO 3046/1…7 (1995)

Reciprocating internal combustion engines - performance

Part 1: Standard reference conditions and declarations of power, fuel and lubricating oil consumption andtest method

Part 3: Test measurementsPart 4: Speed governing Part 5: Torsional vibrations Part 6: Over-speed protectionPart 7: Codes for engine power

Wärtsilä Seminar

International Standard ISO 3046/1 (1995)

STANDARD REFERENCE CONDITIONS:

- Total barometric pressure : 100 kPa. (1,0 bar)- Air temperature: 298 K (25 ºC)- Relative humidity: 30 %- Charge Air coolant temperature: 298 K (25 ºC)

note! Relative humidity of 30% @temp 298 K corresponds to water vapourof 1kPa. Hence the corresponding dry barometric pressure is 99 kPa

Wärtsilä Seminar

Power:

- Declared power “rated power/ output”SI in kilowatt

Metric horse power (hp) = 0,736 kWEngine horse power (HP) = 0,746 kW

Note! When stating the Output, the revolution, the ambient conditionsand load should be mentioned!

Wärtsilä Seminar

Type of power?:

- Declared power- Indicated power- Brake power /shaft- Continuous power- Overload power- Fuel stop power

- ISO power- ISO standard power- Service power- Service standard power- Power adjustment- Power correction

Wärtsilä Seminar

Auxiliaries?:

It is necessary to distinguish those auxiliaries which affect the final shaft output

- dependent auxiliary (engine-driven)- independent auxiliary (separately-driven)

- non-essential auxiliary (far auxiliary)

Wärtsilä Seminar

Fuel oil consumption?:=is the quantity of fuel consumed by an engine per

unit of time at a stated power, under stated ambient conditions, and full load

+ lower heating values of the fuel+ tolerance+ auxiliary

+ power factor + measurement point (Shaft, generators)

note! in general the used SI Unit = g/kWh

Wärtsilä Seminar

Lubricating oil consumption?:

= is “the quantity of lubricating oil consumed by an engine per unit of time at a stated power,

and load”

+ the oil discarded during an engine oil change shall not beincluded into the lube oil declaration

+ a stated period of running shall be declared

note! in general the used SI Unit = litre/ or g/kWh

Note! First 500 Opr-hours is standard period test

Wärtsilä Seminar Turkey

Calorific value of fuels?:

liquid fuel engines“any declared specific fuel consumption of a liquid fuel engine shallbe related to a reference distillate type fuel of lower calorific value

of 42 700 kJ/kg.”

gas engines“any declared specific fuel consumption of a gas engine shall be

related to a stated lower calorific value of the gas. The type of thegas shall be declared”

The (MN) Methane number is concedered to be >80

Wärtsilä Seminar

water sulfur ashvol (%) mass (%) mass (%)

0,3 3 0,01

Wärtsilä Seminar

LHV vs Sulfur vs SFOC

198,71

205,11

201,63200,27

203,47

386003880039000392003940039600398004000040200404004060040800

1 2 3 4 5

Sulfur (mass %)

LHV

(kJ/

kg)

194,00

196,00

198,00

200,00

202,00

204,00

206,00

SFOC

(g/k

Weh

) to

l.0

LHV (kJ/kg)

SFOC (g/kWh)

water density ashvol (%) kg/m3 mass (%)

0,3 995 0,01

Wärtsilä Seminar

Heat balance?:fuel input Fi = B * Q

where:B = gross fuel oil consumption in (kg/s)Q = net calorific value in (kJ/kg)

Cooling water Pcool = m * c * dtwhere:

m = the massflow of the water (kg/s)c = thermal conductivity for water (4,18 kJ/kgK)dt= temperature rise (K)

Wärtsilä Seminar

Exhaust gases Pexh. = m * c * dt

where: m = the mass-flow of the exhaust gas in (kg/s)c = thermal conductivity for gases (1,045 kJ/kgK)dt= temperature difference of gases (K)

The “dt” is the exhaust gas temp. minus the ambient temperature.

Power output P = 1,31 * (D*D) * S * Na * Z * Pme

where: D = piston diameter (m)S = stroke (m)Z = number of cylindersPme = calculated mean effective pressure (bar)Na = working cycle per minute (rpm/2)

Wärtsilä Seminar

Efficiency?:In the diesel engine, injected fuel is not completely changed to mechanicalenergy. The energy changed to useful work is named as total efficiency (ne)

ne = (P/be)*Q

Where: P = output , be = s.f.o.c and Q = fuel net H.V

the easiest way to calculated the efficiency is

(Efficiency) = Output / Input measured in (%)

Wärtsilä Seminar

01020304050607080

0

5

10

15

20

25

30

Mean Temp, °C

M. Relative humidity, %

Wärtsilä Seminar

0

10

20

30

40

50

60

70

80

Avr Jan Feb March Apr il May June July Aug Sep Oct Nov Dec

M. Relative humidity, %Mean Temp, °C

Wärtsilä Seminar

Operating data?In case the engine power will be utilised under more difficult conditionsthan those mentioned or stated in the sales documents. Otherwise, theengine manufacturer can give advice about the correct output reduction.As a guideline additional reduction may be calculated as follows:

Reduction factors = -(a + b + c)

where: a = 0,5 % for every ºC on CA exceeds the I.S.O ref. conditions b = 1 % for every 100 m level above I.S. O ref. conditionsc = 0,4 % for every ºC on CW exceeds the I.S.O ref. conditions

Wärtsilä Seminar Turkey

Wärtsilä 18V46/ Performance (kWe) @ 100 m.a.s.l (m)

17 024

7 000

8 000

9 000

10 000

11 000

12 000

13 000

14 000

15 000

16 000

17 000

18 000

10 15 20 25 30 35 40Ambient Temperature, °C

Gen

erat

or O

utpu

t in

kWe

Derating according to ISO 3064

Derating according to Wartsilä

Wärtsilä Seminar

18V46`s SFOC, g/kWh vs Engine load, %

201,9201,0

204,0

210,0

195,0

197,0

199,0

201,0

203,0

205,0

207,0

209,0

100,0 90,0 75,0 55,0Engine load,%

SFO

C, g

/kW

h

LHV = 40 047 kJ/kg and Ambient T= 25 °C

Wärtsilä Seminar18V46`s SFOC, g/kWh VS Ambient temp, °C

at 100 a.s.l (m)

201,9

202,5

203,2

203,5

201,0

201,5

202,0

202,5

203,0

203,5

204,0

25 30 35 40Ambient temp, °C

SFO

C, g

/kW

h

SFOC, g/kWh

L.H.V = 40 047 kJ/kg