Spray A Nozzle Tip Temperature Measurements Louis‐Marie Malbec, IFPEn  Contributors: Lyle M. Pickett – Sandia National Laboratories Raul Payri, Julien Manin, Michele Bardi – CMT Motores Térmicos Tim Bazyn, Glen Martin – Caterpillar Maarten Meijer, L.M.T. Somers, Technische Universiteit Eindhoven Alan Kastengren, Argonne National Laboratories   Summary of the workshop session:  This session presented Spray A nozzle tip temperature measurements conducted at 6 contributing institutions:  Sandia, IFPEn, CMT, Caterpillar, TUE and Argonne.    As an introduction, the fact that it is impossible to measure the fuel right at the outlet of the injector was reminded. The measurement techniques and results shown in this presentation were thus attempts to access this fuel temperature as close as possible, through the measurement of the nozzle body temperature.  The  first  part  of  the  presentation  described  the  different  devices  used  by  the contributing institutions, with an emphasis on the impact of the characteristics of the vessels on the fuel temperature: 

• For  continuous  flow  vessels  (CMT,  CAT)  or  cold  flow  vessels  (Argonne),  the vessel walls  and ambient gas  temperature are  constant,  so  the  injector  is  in steady state (no temporal evolution of its temperature). 

• For  preburn  vessel,  the  ambient  gas  temperature  is  increasing  during  the combustion  and  then  decreasing  during  the  cool  down  process.  The temperature of the injector and of the fuel is thus changing with time.  

Besides,  continuous  flow  vessels  and  preburn  vessel  require  cooling  systems  to control the injector (in the cold flow vessel, the injector is heated). The geometry of these cooling systems and their ability to limit the heat rise may have an effect on the fuel temperature. At  last,  a  ceramic  cover  is  used  to protect  the nozzle  tip  from  the  ambient  gas hot temperatures, and thus also to limit the temperature rise of the fuel.   In the second part, the three different techniques used by the institutions to measure the nozzle tip temperature were presented.  The first one consists in putting a thermocouple on the injector’s body, quite far from the nozzle  tip. This  type of measurement  is  relevant when  the  injector  is  in  steady state and has been performed by CMT an Argonne. The  second  one,  carried  out  at  IFPEn,  is  based  on  the  Laser  Induced Phosphorescence  (LIP),  which  allows  the measurement  of  the  temperature  of  the surface of the nozzle tip, and its evolution during the preburn event.   

The  last  one  requires  the  use  of  a  dummy  injector  equipped  with  a  K‐type thermocouple. This technique allows the measurement of the temperature within the sac volume, and gives access to its temporal and spatial evolution. At the moment of the workshop, only Sandia, TUE and CAT have used this dummy injector.   In the third part, of the presentation, the results were analyzed.  The  temperature  measured  in  the  sac  volume  with  the  dummy  injector  is  first compared between Sandia and TUE. This comparison shown great differences both in  the  amplitude  of  the  temperature  rise  during  the  preburn,  and  of  its  evolution during the cool down event. But it is difficult to know whether these differences are due  to  variations  in  the  efficiency  of  the  ceramic  shields,  in  the  efficiency  of  the cooling systems or in the cool down behaviors. So no conclusion was drawn so far. The effect of  the ceramic shield has also been investigated by  IFPEn (LIP) and TUE (dummy  injector).  The  results  shown  similar  temperature  evolutions,  however  at different  levels,  for theses two institutions,  in spite of  the different techniques used. The temperature of the surface of the nozzle tip seems thus to be strongly correlated with the sac volume temperature. Moreover, the ceramic shield used by TUE seems to be  slightly  more  efficient  than  IFPEn  one’s,  as  the  temperature  rise  is  higher  at IFPEn. At  last,  the  use  of  the  dummy  injector  also  allowed  assessing  the  temperature gradients within the injector (Sandia, TUE, CAT). This showed a slight decrease of the temperature when the distance to the sac volume increases, but no conclusion can be drawn concerning the effect of such a gradient on the injected fuel temperature.  As  a  conclusion,  the difficulty  to  correlate  the different  temperature measurements with the real temperature of the injected fuel and its evolution was underlined.   Recommendations:  

• In  order  to  assess  and  control  the  temperature  of  the  injected  fuel,  the temperature must be measured in the sac volume. 

• The  dummy  injector  technique  is  the  best  one  to  access  the  sac  volume temperature because of  its  simplicity  (the post  treatment  is  also quite  easy) and of its accuracy. 

• The use of a ceramic shield is a good way to limit the temperature rise of the sac volume. The design of TUE one’s seems to be the more efficient. 

• When using a cooling system, people must be careful of the corrosion that can be induced by water condensation on the injector tip. 

  Discussion items from the workshop:  

• As  an  answer  to  a  question  on  the  effect  of  the  fuel  temperature  on  liquid length,  it  was  reminded  that  this  was  of  first  order,  and  thus  needs  to  be controlled as precisely as possible. 

 • The modelers underlined that for the moment, there was no model able to take 

into  account  the  heat  transfers  between  the  fuel  and  the  injector’s  body within the nozzle hole. Thus, the temperature of the injected fuel right at the outlet  of  the  injector  can  not  be  inferred  from  its  temperature  in  the  sac volume. 

Renewable energies | Eco-friendly production | Innovative transport | Eco-efficient processes | Sustainable resources

Nozzle tip and injector's body temperature measurements

Spray A and hydraulic characterization

Gilles Bruneaux Louis-Marie MalbecGilles Bruneaux, Louis-Marie MalbecIFPEn

Lyle M. Pickett Raul Payri, Julien Manin, Michele Bardiy e c eSandia National Laboratories

au ay , Ju e a , c e e a dCMT Motorés Termicos

Tim BazinCaterpillar

rgie

s no

uvel

les

p

Alan KastengrenArgonne National Laboratories

Maarten Meijer, L.M.T SomersTechnische Universiteit Eindhoven

© 2

011

-IFP

Ene

r

ECN Workshop 13-14 May 2011 – Ventura – Nozzle tip and injector’s body temperature measurements

IFPEN P b ti l ECN i tIFPEN Precombustion vessel ECN experiments

2009-2010Spray A

2011Multi points ambient temperature measurements: 5 thermocouplesmeasurements: 5 thermocouples probeNon reacting & reacting velocity fields: PIVSoot: LII + TEM

2012LIF formaldehyde + OH

Ene

rgie

s no

uvel

les

Lyle M. Pickett, Caroline L. Genzale, Gilles Bruneaux, Louis-Marie Malbec, Laurent Hermant, Caspar Christiansen, and Jesper Schramm, Comparison of Diesel Spray Combustion in Different High-Temperature, High-Pressure Facilities, SAE Int. J. Engines December 2010 3:156-181, SAE paper 2010-01-2106.

B G M li D St d f th Mi i d C b ti P f C ti Sh t D bl Di l

© 2

011

-IFP

ECN Workshop 13-14 May 2011 – Ventura – Nozzle tip and injector’s body temperature measurements2

Bruneaux, G., Maligne, D., Study of the Mixing and Combustion Processes of Consecutive Short Double Diesel Injections, SAE Int. J. Engines 2(1):1151-1169, 2009. (SAE 2009-01-1352)

Bruneaux, G., Combustion Structure of Free and Wall Impinging Diesel Jets by Simultaneous Laser Induced Fluorescence of Formaldehyde, PAH and OH, International Journal of Engine Research, volume 9, issue 3, 2008.

ContextContext

Behavior of the spray and characteristics of the combustion depend p y pon the temperature of the injected fuel.Fuel temperature is an input of the combustion models.

T t f S A diti f l i j t d t 90°C

=> Need for measuring and regulating the temperature of the injected fuel.

Target for Spray A conditions: fuel injected at 90°C.

90°C

Ene

rgie

s no

uvel

les needle

(open)

© 2

011

-IFP

ECN Workshop 13-14 May 2011 – Ventura – Nozzle tip and injector’s body temperature measurements3

ContextContext

Ideally we want to measure/controlIdeally, we want to measure/control the temperature:• of the fuel• just at the nozzle tipj p• during the whole injection

Needle

Ene

rgie

s no

uvel

les

© 2

011

-IFP

ECN Workshop 13-14 May 2011 – Ventura – Nozzle tip and injector’s body temperature measurements4

ContextContext

Practically, we can measure the ytemperature:• of the injector body• at different locations• without injection and without fuel

Needle

Ene

rgie

s no

uvel

les What is the real

temperature of the injected fuel?

© 2

011

-IFP

ECN Workshop 13-14 May 2011 – Ventura – Nozzle tip and injector’s body temperature measurements5

injected fuel?

Institutions and facilitiesInstitutions and facilities

CMTCaterpillar

Temperature measurements are not time dependantCaterpillar

TUE (Eindhoven) Temperature measurementsSandia Nat. LabsIFPEn

Temperature measurements are time dependant

Ene

rgie

s no

uvel

les

ArgonneTemperature measurements are not time dependant, i j t i h t d

© 2

011

-IFP

ECN Workshop 13-14 May 2011 – Ventura – Nozzle tip and injector’s body temperature measurements6

injector is heated

Continuous flow vesselContinuous flow vessel

Heated wallsHeated walls=> the injector needs to be cooled

Constant and tunable temperature of the ambient air=> the injector's temperature is in steady state (except for

the effect of the fuel flow during injection)

CMT CAT

Ene

rgie

s no

uvel

les

© 2

011

-IFP

ECN Workshop 13-14 May 2011 – Ventura – Nozzle tip and injector’s body temperature measurements7

Precombustion vessel

Heated walls

Precombustion vessel

Heated walls=> the injector needs to be cooled

A precomb is necessary to increase the temperature IFPEn Sandia TUE

within the vessel. Injection during the cooling of the gases.

=> the ambient air temperature is varying before injection: p y g jthe injector's temperature is not in a steady-state.

Ene

rgie

s no

uvel

les

© 2

011

-IFP

ECN Workshop 13-14 May 2011 – Ventura – Nozzle tip and injector’s body temperature measurements8

Cold flow vesselCold flow vessel

Cold flowCold flow=> the injector needs to be heated

Constant temperature of the ambient air=> the injector's temperature is in steady state (except for

the effect of the fuel flow during injection)the effect of the fuel flow during injection)

Ene

rgie

s no

uvel

les

© 2

011

-IFP

ECN Workshop 13-14 May 2011 – Ventura – Nozzle tip and injector’s body temperature measurements9

Institutions and facilitiesInstitutions and facilitiesCMT TUE Sandia

IFPEN CATCeramic shields

Ene

rgie

s no

uvel

les

© 2

011

-IFP

ECN Workshop 13-14 May 2011 – Ventura – Nozzle tip and injector’s body temperature measurements10

Temperature measurement methodsTemperature measurement methodsThermocouple in dummy injector

CAT TUE Sandia

Ene

rgie

s no

uvel

les

K-type thermocouple(50 i )

© 2

011

-IFP

ECN Workshop 13-14 May 2011 – Ventura – Nozzle tip and injector’s body temperature measurements11

(50microns)

Temperature measurement methodsTemperature measurement methodsCMT TUE Sandia

IFPEN CAT

Ene

rgie

s no

uvel

les

© 2

011

-IFP

ECN Workshop 13-14 May 2011 – Ventura – Nozzle tip and injector’s body temperature measurements12

Temperature measurement methodsTemperature measurement methodsLaser Induced Phosphorescence (LIP)

IFPENIFPEN

Ene

rgie

s no

uvel

les Thin phosphor layer

© 2

011

-IFP

ECN Workshop 13-14 May 2011 – Ventura – Nozzle tip and injector’s body temperature measurements13

Temperature measurement methodsTemperature measurement methodsCMT TUE Sandia

IFPEN CAT

Ene

rgie

s no

uvel

les

© 2

011

-IFP

ECN Workshop 13-14 May 2011 – Ventura – Nozzle tip and injector’s body temperature measurements14

Temperature measurement methodsTemperature measurement methodsThermocouple on real injector

CMT

Continuous flow

CMT

vessel:Constant temp.

Ene

rgie

s no

uvel

les

T t

© 2

011

-IFP

ECN Workshop 13-14 May 2011 – Ventura – Nozzle tip and injector’s body temperature measurements15

Temperature sensor

ResultsResultsTransient temperature: TC in dummy injector, precomb. vessel (TUE Sandia)(TUE, Sandia)

110

120

130

re (degC)

TUE

Sandia •Amplitude is higher for Sandia’s vessel.

0 1 2 3 4 5 680

90

100

Temperatu

0 mmDistance to nozzle 2

•Temporal evolution is different

•Efficiency of the ceramic shield?

120

130

C)

TUE

Sandia

0 1 2 3 4 5 6Time ASI (s)

120

130

)

TUE

Sandia

Distance to nozzle 2mm •Efficiency of the cooling system?•Different cool down behaviour?

Ene

rgie

s no

uvel

les

90

100

110

Temperature (degC

1 mm90

100

110

Temperature (degC)

2

•Effect on injected fuel temperature?

© 2

011

-IFP

ECN Workshop 13-14 May 2011 – Ventura – Nozzle tip and injector’s body temperature measurements16

0 1 2 3 4 5 6 780

Time ASI (s)

1 mm0 1 2 3 4 5 6 7

70

80

Time ASI (s)

2 mm

ResultsResultsTransient temperature: cover effect

120

e (degC)

Sandia w/o cover

Sandia w cover

IFPEn

IFPEn20°C

100

mperature TUE w/o cover

TUE w cover10°C

20 C

60

80

surface tem Similar evolutions

Similar evolutions Ceramic shields allows to limit heat transfers towards the

Ene

rgie

s no

uvel

les

0 2 4 6 840

Ti ft i iti ( )

Nozzle 

heat transfers towards the injector=> the control of the injected fuel temperature is more efficient

© 2

011

-IFP

ECN Workshop 13-14 May 2011 – Ventura – Nozzle tip and injector’s body temperature measurements17

Time after ignition (s) efficient.

ResultsResultsSteady state tip temperature

120

CAT 900K

CAT 850KThese results give an idea of the temperature gradients

80

100

ure (degC)

CAT 850K

CAT 950K

Sandia

TUE

of the temperature gradients within the injector.

=> Effect on injected fuel temperature?

60

80

Tem

peratu

Ene

rgie

s no

uvel

les

0 5 10 15 20 25 3040

Distance to nozzle (mm)

© 2

011

-IFP

ECN Workshop 13-14 May 2011 – Ventura – Nozzle tip and injector’s body temperature measurements18

Distance to nozzle (mm)

SynthesisSynthesis

Recommendations for the “best” experimental eco e da o s o e bes e pe e amethods

Use dummy injector to control the nozzle tip temperature at 90°C for spray A. Post-processing is quite easy.p y p g q yUse a ceramic shield to limit heat transfers towards injectorBe careful with low injector temperature (corrosion)

ModellingThe tip temperature and its evolution strongly depends on the experimental setup

Ene

rgie

s no

uvel

les experimental setup

What is the real temperature of the injected fuel? We can assume an experimental uncertainty of about 30K.

© 2

011

-IFP

ECN Workshop 13-14 May 2011 – Ventura – Nozzle tip and injector’s body temperature measurements19