Ford's answers to the NHTSA 6.7 Investigation

[ricatic]

There was a request for a link to Ford's answer's to the NHTSA investigation posted on a previous thread, since closed. Here is the link:

Ford's NHTSA Answers to the 6.7 investigation

This PDF is over 20 pages long. There are some interesting statements contained in the documents. My favorite is the one where Ford says they buy the pump from Bosch as a "black box" and do no testing of the component. It is closely followed by the tantamount admission that the pump will not provide a long service life when exposed to the poor lubricity fuel found in the US. You will have to do the math using the sales versus failure tables for the US and Canadian trucks. Eye opening difference to say the least...

Regards

[Engineer9860]

NHIrish wrote:

Engineer9860 wrote:
Found this on dieselplace.com: (apologies if it is a repost)

Delphi

I went through the LML (CP4 affected) section over there looking for doom, and gloom. Not much discussion on Duramax CP4 HPFP failures.

Looks like ricatic is a man of legend on the Chevy diesel forums as well. 😉

Old news...but it sure tells you why you better get yourself a good fuel additive, doesn't it. The bottom line seems to be that these fuel pumps are inappropriate for the US fuel market. You can decide for yourself if you read this statement and then the US and Euro fuel standards.

Stanadyne Performance Formula is the name I see popping up most often.

I think the general consensus is to stay away from any additive that dissolves the water droplets. The water needs to remain in a state that will allow the water separator to remove them from the fuel stream most effectively.

Also, guys with the LML Duramax are switching to a CAT 2 micron primary, and a 1 micron secondary fuel filter.

[NewsW]

The common statement's problem is that they can bleat, but in this market, the engine / fuel system makers do not dictate.

http://www.globaldenso.com/en/topics/091012-01.html

That is the 2009 version.

There is a 2004 version that was done around the time CP 4 was designed.

Fuel system makers did not get their way on lubricity, and they have to make a pump to what works locally.

Oh.. I am more and more convinced that lubricity is not necessarily the main issue.

[NHIrish]

Engineer9860 wrote:
Found this on dieselplace.com: (apologies if it is a repost)

Delphi

I went through the LML (CP4 affected) section over there looking for doom, and gloom. Not much discussion on Duramax CP4 HPFP failures.

Looks like ricatic is a man of legend on the Chevy diesel forums as well. 😉

Old news...but it sure tells you why you better get yourself a good fuel additive, doesn't it. The bottom line seems to be that these fuel pumps are inappropriate for the US fuel market. You can decide for yourself if you read this statement and then the US and Euro fuel standards.

[NHIrish]

blackeyed1 wrote:
Keep beating the horse, be it either alive or dead, until the truth comes out. I have a 2008 6.4L that is alive and well for now, but I'll never know for sure it stays that way. some of you think it's no big deal, but if Ford or my insurance denies repairs or payment based on this pump or fuel issues, I for one could not afford $10-12,000 for a new engine. I do the draining, filters, etc regularly per the diesel supplement. But there is a fear each day I take it out that it could be my last. Would you like that feeling? I doubt it.
I do have a back up plan should I have a catastrophic failure that my insurance or Ford will not cover. But I sure won't say it here.

Exactly right. Unfortunately, it often takes this type of action to get companies to do the right thing. Keep beating.

[Engineer9860]

Found this on dieselplace.com: (apologies if it is a repost)

Delphi

I went through the LML (CP4 affected) section over there looking for doom, and gloom. Not much discussion on Duramax CP4 HPFP failures.

Looks like ricatic is a man of legend on the Chevy diesel forums as well. 😉

[durallymax]

The gear pump on the backside of the CP3 is what draws the fuel from the fuel tank to the pump.

There always have been relief valves located throughout the system on the common rails. A high pressure on either in the rail or junction block, the pumps internal regulation and the injectors themselves.

I do not know how the Cp4 pump/system is working. on the CP3 setups fuel was only commanded when needed. If the ECM was commanding 23,000psi and the rail was at 23,000psi the pump would only work to maintain 23,000psi.

I did read somewhere about the CP4 needing to be timed. Could be misinformation though. The CP3 never needed timing.

[NewsW]

Thermal Effect Simulation in High-Pressure Injection System Transient Flows
Number: 2004-01-0532

Published: 2004-03-08



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Content Type: Technical Paper


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Publisher: SAE International

Language: English
DOI: 10.4271/2004-01-0532
Author(s): A. E. Catania - IC Engines Advanced Laboratory - Politecnico di Torino; A. Ferrari - IC Engines Advanced Laboratory - Politecnico di Torino; M. Manno - IC Engines Advanced Laboratory - Politecnico di Torino; E. Spessa - IC Engines Advanced Laboratory - Politecnico di Torino
Citation:
Catania, A., Ferrari, A., Manno, M., and Spessa, E., "Thermal Effect Simulation in High-Pressure Injection System Transient Flows," SAE Technical Paper 2004-01-0532, 2004, doi:10.4271/2004-01-0532.


Citation

Abstract:

Temperature variations due to compressibility effects of the liquid fuel were evaluated, for the first time in high-pressure injection system simulation, by employing the energy conservation equation, in addition to the mass-continuity and momentum-balance equations, as well as the constitutive state equation of the liquid. To that end, the physical properties (bulk elasticity modulus, thermal expansivity, kinematic viscosity) of the fluid were used as analytic functions of pressure and temperature obtained by interpolating carefully determined experimental data. Consistent with negligible thermal effects of heat transfer and viscous power losses involved in the flow process, the equation of energy was reduced to a state relation among the fluid thermodynamic properties, leading to a barotropic flow model. A comparison between isentropic and isothermal evolutions in the pure liquid regions was carried out for evaluating the influence of the temperature variation simulation on the macroscopic results given by local pressure time-histories. Furthermore, for cavitation analysis, different thermodynamic transformations of the vapor-liquid mixture were considered and compared.

A recently developed conservative numerical model of general application, including a comprehensive thermodynamic approach to the simulation of cavitation, based on a barotropic flow model, was applied and assessed through the comparison of prediction and measurement results on a diesel injection system performance.

A conventional pump-line-nozzle system was considered for this purpose, being relevant to the model evaluation due to its pressure wave dynamics and also because it was subject to severely cavitating flow conditions at part loads. Predicted time-histories of injector needle lift and pressure at two pipe locations, for two engine loads at the same pump speed, were compared to experimental results, substantiating the validity and robustness of the conservative model taking thermal effects into account in high-pressure injection system transient flow simulation with great degree of accuracy, even in the presence of cavitation induced discontinuities, with minor oscillation problems. The thermal effects due to the temperature variations in the liquid fuel and in the cavitating mixture were analyzed and discussed.

[NewsW]

Paper dealing with pressure waves

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Common Rail without Accumulator: Development, Theoretical-Experimental Analysis and Performance Enhancement at DI-HCCI Level of a New Generation FIS
Number: 2007-01-1258

Published: 2007-04-16



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Content Type: Technical Paper


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Publisher: SAE International

Language: English
DOI: 10.4271/2007-01-1258
Author(s): A. E. Catania - Politecnico di Torino; A. Ferrari - Politecnico di Torino; A. Mittica - Politecnico di Torino; E. Spessa - Politecnico di Torino
Citation:
Catania, A., Ferrari, A., Mittica, A., and Spessa, E., "Common Rail without Accumulator: Development, Theoretical-Experimental Analysis and Performance Enhancement at DI-HCCI Level of a New Generation FIS," SAE Technical Paper 2007-01-1258, 2007, doi:10.4271/2007-01-1258.


Citation

Abstract:

An innovative hydraulic layout for Common Rail (C.R.) fuel injection systems was proposed and realized. The rail was replaced by a high-pressure pipe junction to have faster dynamic system response during engine transients, smaller pressure induced stresses and sensibly reduced production costs. Compared to a commercial rail, whose inside volume ranges from 20 to 40 cm 3 , such a junction provided a hydraulic capacitance of about 2 cm 3 and had the main function of connecting the pump delivery to the electroinjector feeding pipes. In the design of the novel FIS layout, the choice of high-pressure pipe dimensions was critical for system performance optimization. Injector supplying pipes with length and inner diameter out of the actual production range were selected and applied, for stabilizing the system pressure level during an injection event and reduce pressure wave oscillations.

The new injection system was realized and subjected to experimentation under engine-like working conditions on a high performance Moehwald-Bosch MEP2000-CA4000 test bench. The injection performance of the new system was shown to be similar to those of a commercial C.R., for a single injection. Besides, for multiple injections, the innovative layout dynamics was substantially improved by a reduced dependence of the overall injected fuel amount on dwell-time (DT) in sequential injection events. Hydraulic layout solutions preventing the occurrence of resonance flow phenomena among injectors were used to minimize fluid dynamic interference among injectors . The results confirmed that the rail capacitance was not a key parameter in pressure wave disturbance attenuation, whereas injector inlet-pipe sizes did have a considerable effect on these.

In addition, a modification of latest solenoid-generation commercial Multijet electroinjector was realized so as to sensibly reduce the limits of DT for fusion-free sequential injection shots, thus enhancing such component at HCCI combustion application level. The design of the injector based on an integrated experimental-theoretical analysis of system dynamics, was carried out using a previously developed C.R. numerical model. Experimental results on injector characteristics were discussed.
References:

CataniaA.E., FerrariA., and MitticaA., 2006, “High Pressure Rotary Pump Performance in Multijet C.R. Systems”, ASME ESDA Paper 2006-95590.
Bosch Internal Technical Report.
CataniaA.E., FerrariA., and MannoM., 2005, “Parametric Analysis of Layout Effects on Common Rail Multiple-Injections”, ASME ICED Fall Technical Conference, Paper No. ICEF2005-1288.
U.S. Department of Energy, 2001, “Homogeneous Charge Compression Ignition (HCCI) Technology - A report to the U.S. Congress”.
FosterD.E., and NajtP.M., 1983, “Compression-Ignited Homogeneous Charge Combustion”, SAE Paper No. 830264.
StanglmaierR.H., and RobertsC.E., 1999, “Homogeneous Charge Compression Ignition (HCCI): Benefits, Compromises, and Future Engine Applications”, SAE Paper No. 1999-01-3682.
GrayA.W., and RyanT.W., 1997, “Homogeneous Charge Compression Ignition (HCCI) of Diesel Fuel”, SAE Paper No. 971676.
AndoH., and KuwaharaK., 2001, “A keynote on future Combustion Engines”, SAE Paper No. 2001-01-0248.
SuW., WangH., and LiuB., 2005, “Injection Mode Modulation for HCCI Diesel Combustion”, SAE Paper No. 2005-01-0117.
HelmantelA., and DenbrattI., 2004, “HCCI Operation of a Passenger Car Common Rail DI Diesel Engine with Early Injection of Conventional Diesel Fuel”, SAE Paper No. 2004-01-0935.
BuchwaldR., BrauerM., BlechsteinA., SommerA., and KahrstedtJ., 2004, “Adaption of Injection System Parameters to Homogeneous Diesel Combustion”, SAE Paper No. 2004-01-0936.
SuW., ZhangX., LinT., PeiY., and ZhaoH., 2004, “Study of Pulse Spray, Heat Release, Emissions and Efficiencies in a Compound Diesel HCCI Combustion Engine”, Fall Technical Conference of the ASME ICED, Paper No. ICEF2004-927.
CataniaA.E., FerrariA., and MannoM., 2005, “Development and Application of a Complete Common Rail Injection System Mathematical Model for Hydrodynamic Analysis and Diagnostics”, Spring Technical Conference of the ASME ICED, Paper No. ICES 2005-1018. Submitted for publication in ASME Transactions, Journal of Engineering for Gas Turbines and Power.
CataniaA.E., Ferrari and SpessaE., 2006, “Numerical-Experimental Study and Solutions to Reduce the Dwell Time Threshold for Fusion-Free Consecutive Injections in a Multijet Solenoid-Type C.R. System”, Spring Technical Conference of the ASME ICED, Paper No. ICES 2006-1369. Submitted for publication in ASME Transactions, Journal of Engineering for Gas Turbines and Power.
CataniaA. E., FerrariA., MannoM., PellettieriR., and SpessaE., 2004, “Development, Setup and Instrumentation of a High-Performance Diesel Injection System Test Bench: Preliminary Experimental Results on the Dynamics of a C.R. System”, Proceedings, LIX ATI Congress, 2, pp. 821-834 .
BoschW., 1966, “The Fuel rate Indicator: a New Measuring Instrument for Display of Individual Injection Characteristics”, SAE Paper No. 660749.
BarattaM., CataniaA. E., and FerrariA., “Hydraulic Circuit Design Keys to Eliminate the dependence of the Injected Fuel on Dwell Time in Multijet Common Rail Systems”, Spring Technical Conference of the ASME ICED, Paper No. ICES 2006-1426.
CataniaA. E., FerrariA., MannoM., and SpessaE., 2005, “Experimental Investigation of Dynamics Effects on Multiple-Injection Common Rail System Performance”, Spring Technical Conference of the ASME ICED, Paper No. ICES 2005-1108. Submitted for publication in ASME Transactions, Journal of Engineering for Gas Turbines and Power.
CataniaA.E., FerrariA., MannoM., and SpessaE., 2006, “A Comprehensive Thermodynamic Approach to Acoustic Cavitation Simulation in High-Pressure Injection Systems by a Conservative Homogeneous Barotropic-Flow Model”, ASME Transactions, Journal of Engineering for Gas Turbines and Power., Vol. 128, pp. 434-445.

[NewsW]

Link Between Cavitation Development and Erosion Damage in Diesel Injector Nozzles
Number: 2007-01-0246

Published: 2007-04-16



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Content Type: Technical Paper


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Publisher: SAE International

Language: English
DOI: 10.4271/2007-01-0246
Author(s): M. Gavaises - The City University London; D. Papoulias - The City University London; A. Andriotis - The City University London; E. Giannadakis - The City University London; A. Theodorakakos - Fluid Research Co.
Citation:
Gavaises, M., Papoulias, D., Andriotis, A., Giannadakis, E. et al., "Link Between Cavitation Development and Erosion Damage in Diesel Injector Nozzles," SAE Technical Paper 2007-01-0246, 2007, doi:10.4271/2007-01-0246.


Citation

Abstract:

Cavitation formation and development inside Diesel injector nozzles suffering from erosion damage has been investigated using enlarged transparent nozzle replicas and computational fluid dynamics (CFD) simulations. Cavitation erosion has been observed at different locations within the nozzle. These have included the top surface inside the nozzle hole next to its entry, the 3o'clock and 9c'clock hole side-inlets as well as at the needle seat area. Instantaneous and time-averaged high-speed CCD images of cavitation have verified that cavitation erosion sites are found in areas of cavitation bubble collapse. This has been further supported by CFD predictions obtained using the measured injection pressure and needle lift traces, both for the pilot and main injection events. The cavitating flow regimes associated with these erosion sites correspond to geometrically-induced hole cavitation, the string cavitation and the needle seat cavitation, respectively. Averaging of the simulated flow field over the injection duration has allowed estimation of nozzle wall surface flow parameters indicative of erosion. These parameters have included the bubble collapse acoustic pressure and its standard deviation. Comparison of the relative magnitude of these parameters for different nozzle designs has led to the conclusion that the range of values predicted are orders of magnitude greater for the nozzles that exhibit cavitation damage relative to those found to be erosion-free. Empirical validation of the method is achieved through manufacturing of nozzles which have computationally indicated less probability for cavitation erosion, and which after sufficient running time have been found to be free of cavitation erosion.

[NewsW]

The Influence of Variable Fuel Properties in High-Pressure Diesel Injectors
Number: 2009-01-0832

Published: 2009-04-20



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Content Type: Technical Paper


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Publisher: SAE International

Language: English
DOI: 10.4271/2009-01-0832
Author(s): E. Giannadakis - City University; M. Gavaises - City University; A. Theodorakakos - Fluid Research Co. , City University
Citation:
Giannadakis, E., Gavaises, M., and Theodorakakos, A., "The Influence of Variable Fuel Properties in High-Pressure Diesel Injectors," SAE Technical Paper 2009-01-0832, 2009, doi:10.4271/2009-01-0832.


Citation

Abstract:

High pressurization of Diesel fuel in modern common-rail injectors , in addition to its effect on spray atomization, can result to increase of fuel density and viscosity in comparison to atmospheric conditions; moreover, due to the sharp de-pressurization experienced by the fuel at the inlet of the injection holes significant gradients of the above properties are established. Consequently, the characteristics of cavitation taking place at the entrance to the injection holes are affected. The present study quantifies the role of these effects in automotive Diesel injectors operating at pressures in excess of 1500 bar through use of a cavitation CFD model. The flow solver is accordingly modified to account for such effects during the solution of the conservation equations. Two different injector designs have been considered, both based on the same sac-type nozzle body; one with sharp-inlet cylindrical holes and one with tapered holes with inlet rounding. Pressurization of the fuel affects mainly liquid viscosity, which can increase up to approximately 10 times in comparison to atmospheric conditions, while density differences do not exceed 10%. The results indicate that for the nozzle with sharp-inlet cylindrical holes, in which the flow is highly cavitating and for this reason can be referred to as ‘low efficiency’, the consideration of variable fuel properties effects due to pressurization is overshadowed by cavitation effects; moreover, the predicted discharge coefficient considering variable density and viscosity is comparable with the one obtained using constant fuel properties, having a 2% difference. In contrast to this, these effects become relatively more important for the ‘high efficiency’ nozzle equipped with tapered holes, which cavitates much less in comparison to the cylindrical one. For the tapered hole nozzle it has been found that when variable density and viscosity effects are considered the predicted average flowrate is approximately 4% lower than when constant properties are used.

[NewsW]

BenK

Cavitation!


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Analysis of Transient Cavitating Flows in Diesel Injectors Using Diesel and Biodiesel Fuels
Number: 2010-01-2245

Published: 2010-10-25





Content Type: Technical Paper



Publisher: SAE International

Language: English
DOI: 10.4271/2010-01-2245
Author(s): Michele Battistoni - Universita degli Studi di Perugia; Carlo Nazareno Grimaldi - Universita degli Studi di Perugia
Citation:
Battistoni, M. and Grimaldi, C., "Analysis of Transient Cavitating Flows in Diesel Injectors Using Diesel and Biodiesel Fuels," SAE Int. J. Fuels Lubr. 3(2):879-900, 2010, doi:10.4271/2010-01-2245.


Citation

Abstract:

The aim of the paper is the comparison of the injection process with different fuels , i.e. a standard diesel fuel and a pure biodiesel. Multiphase cavitating flows inside diesel nozzles are analyzed by means of unsteady CFD simulations using a two- fluid approach with consideration of bubble dynamics, on moving grids from needle opening to closure. Two five-hole nozzles with cylindrical and conical holes are studied and their behaviors are discussed taking into account the different properties of the two fuels . Extent of cavitation regions is not much affected by the fuel type. Biodiesel leads to significantly higher mass flow only if the nozzle design induces significant cavitation which extends up to the outlet section and if the injector needle is at high lift. If the internal hole shaping is able to suppress cavitation, the stabilized mass flows are very similar with both fuels . On the contrary, as long as the lifts are small and the flow is turbulent, diesel fuel gives higher mass flows due to lower frictions along the needle seat and the nozzle walls. Detailed analyses of the injection processes are presented, including flow pattern development inside the nozzles.
References:

Grimaldi, C.N., Postrioti, L., Battistoni, M., Millo, F., “Common-Rail HSDI Diesel Engine Combustion and Emissions With Fossil/Bio-Derived Fuel Blends,” SAE Technical Paper 2002-01-0865, 2002, doi:10.4271/2002-01-0865.
Priesching, P., Pavlovic, Z., Ertl, P., Del Giacomo, N., Beatrice, C., Mancaruso, E., Vaglieco, B.M., “Numerical and Experimental Investigation of the Influence of Bio-Diesel Blends on the Mixture Formation, Combustion and Emission Behavior of a Modern HSDI Diesel Engine,” SAE Technical Paper 2009-24-0041, 2009, doi:10.4271/2009-24-0041.
Patterson, J., Hassan, M.G., Clarke, A., Shama, G., Helgardt, K. and Chen, R., “Experimental Study of DI Diesel Engine Performance using Three Different Biodiesel Fuels,” SAE Technical Paper 2006-01-0234, 2006, doi:10.4271/2006-01-0234.
Lujan, J.M., Tormos, B., Salvador, F.J., and Gardar, K., Comparative analysis of a DI Diesel engine fuelled wth biodiesel blends during the European MVEG-A cycle: preliminary study (I), Biomass and Energy, 33(6-7) pp. 941-947.
Lujan, J.M., Bermúdez, V., Tormos, B., Pla, B., Comparative analysis of a DI Diesel engine fuelled wth biodiesel blends during the European MVEG-A cycle: performances and emissions (II), Biomass and Energy, 33(6-7) pp. 948-956.
Postrioti, L., Battistoni, M., Grimaldi, C.N., Millo, F., “Injection Strategies Tuning for the use of Bio-Derived Fuels in a Common Rail HSDI Diesel Engine,” SAE Technical Paper 2003-01-0768, 2003, doi:10.4271/2003-01-0768.
Battistoni, M., Experimental Analysis of a Common-Rail DI Diesel Engine Fuelled with Bio-Derived Alternative Fuels, Ph.D. Thesis, University of Perugia, XVI ciclo, 2004.
Desantes, J., Payri, R., Salvador, F.J., De la Morena, J., “Cavitation Effects On Spray Characteristics In The Near-Nozzle Field,” SAE Technical Paper 2009-24-0037, 2009, doi:10.4271/2009-24-0037.
Gavaises, M., Andriotis, A., “Cavitation Inside Multi-hole Injectors for Large Diesel Engines and Its Effect on the Near-nozzle Spray Structure,” SAE Technical Paper 2006-01-1114, 2006, doi:10.4271/2006-01-1114.
Payri, R., Desantes, J.M., Salvador, F.J., Manin, J., “Influence on Diesel Injection Characteristics and Behavior using Biodiesel Fuels,” SAE Technical Paper 2009-01-0851, 2009, doi:10.4271/2009-01-0851.
Grimaldi, C.N., Postrioti, L., “Experimental Comparison Between Conventional and Bio-derived Fuels Sprays from a Commn Rail Injection System,” SAE Technical Paper 2000-01-1252, 2000, doi:10.4271/2000-01-1252.
Postrioti, L., Grimaldi, C.N., Ceccobello, M., Di Gioia, R., “Diesel Common Rail Injection System Behavior with Different Fuels,” SAE Technical Paper 2004-01-0029, 2004, doi:10.4271/2004-01-0029.
Brennen, C.E., Fundamentals of Multiphase Flows, Cambridge University Press, 2005.
Giannadakis, E., Papoulias, D., Gavaises, M., Arcoumanis, C., Soteriou, C., Tang, W., “Evaluation of the Predictive Capability of Diesel Nozzle Cavitation Models,” SAE Technical Paper 2007-01-0245, 2007, doi:10.4271/2007-01-0245.
Ning, W, Reitz, R.D, Diwakar, R., Lippert, A.M., “A Numerical Investigatin of Nozzle Geometry and Injection Condition Effects on Diesel Fuel Injector Flow Physics,” SAE Technical Paper 2008-01-0936, 2008, doi:10.4271/2008-01-0936.
Wang, X., Su, W., “Influence of Injection Pressure Fluctuations on Cavitation inside a Nozzle Hole at Diesel Engine Conditions,” SAE Technical Paper 2008-01-0935, 2008, doi:10.4271/2008-01-0935.
Chiatti, G., Chiavola, O., Palmieri, F., “Flow Features in Reduced Dwell Time Diesel Injector,” SAE Technical Paper 2008-01-0927, 2008, doi:10.4271/2008-01-0927.
Chiatti, G., Chiavola, O., Palmieri, F., “Injector Dynamic and Nozzle Flow Features in Multiple Injection Modeling,” SAE Technical Paper 2007-24-0038, 2007, doi:10.4271/2007-24-0038.
Avl List GmbH, AVL Fire v.2009 - Eulerian Multiphase, 2009.
Drew, D.A. and Passman, S.L. Theory of Multicomponent Fluids, Springer, New York, 1998.
Alajbegovic, A., Grogger, H.A., Philipp, H., Calculation of Transient Cavitation in Nozzle Using the Two-Fluid Model, ILASS-Americas 99, Conference Proceedings, 1999.
Alajbegovic, A., Meister, G., Greif, D., Basara, B., Three phase cavitating flows in high-pressure swirl injectors, Experimental Thermal and Fluid Science 26(6-7), pp. 677-681, 2002.
Sato, Y. and Sekoguchi, K., Liquid velocity distribution in two-phase bubble flow, Int. J. Multiphase Flow, 2 (79), 1975.
Hanjalic, K., Popovac, M. and Hadziabdic, M., A robust near-wall elliptic relaxation eddy-viscosity turbulence model for CFD, Int. J. of Heat and Fluid Flow, 25(6), pp. 1360-1378, 2004.
Popovac, M., Hanjalic, K., Compound Wall Treatment for RANS Computation of Complex Turbulent Flows and Heat Transfer, Int. J. of Heat and Fluid Flow, 78(2), pp. 177-202, 2007.
Avl List GmbH, AVL Fire v.2009 - CFD Solver, 2009.
Hinze, J.O., Turbulence, McGraw-Hill, New York, 1975.
Payri, F., Margot, X., Patouna, S., Ravet, F., Funk, M., “A CFD Study of the Effect of the Needle Movement on the Cavitation Pattern of Diesel Injectors,” SAE Technical Paper 2009-24-0025, 2009,” doi:10.4271/2009-24-0025.
Ishii, M., Sun, X. and Kim, S., Modeling strategy of the source and sink terms in the two-group interfacial area transport equation, Annals of Nuclear Energy, 30 (13), pp. 1309-1331, 2003.
Perry, R.H., Green, D.W., Perry's Chemical Engineers' Handbook, McGraw-Hill, 1997.
Yuan, W., Hansen, A.C., Zhang, Q., Vapor pressure and normal boiling point predictions for pure methyl esters and biodiesel fuels, Fuel, 84(7-8), pp. 943-950, 2005.
Yuan, W., Hansen, A.C., Zhang, Q., Predicting the temperature dependent viscosity of biodiesel fuels, Fuel, 88(6), pp. 1120-1126, 2009.
Goodrum, J.W., Volatility and boiling points of biodiesel from vegetable oils and tallow, Biomass and Bioenergy 22, pp. 205 - 211, 2002.
Soteriou, C., Andrews, R., Smith, M., “Direct Injection Diesel Sprays and the Effect of Cavitation and Hydraulic Flip on Atomization,” SAE Technical Paper 950080, 1995, doi:10.4271/950080.
Nurick, W.H., Orifice Cavitation and its Effects on Spray Mixing, ASME Journal of Fluids Engineering, 98, pp. 681-687, 1976.
Chaves, H., Knapp, M., Kubitzek, A., Obermeier, F., Schneider, T., “Experimental Study of Cavitation in the Nozzle Hole of Diesel Injectors Using Transparent Nozzles,” SAE Technical Paper 950290, 1995, doi:10.4271/950290.
Lichtarowicz, A.K., Duggins, R.K., Markland, E., Discharge coefficients for incompressible no-cavitating flow through long orifices, J. Mech. Engineering Science, 7(2), pp. 210-219, 1965.
Von Kuensberg Sarre, C., Kong, S.C., Reitz, R.D., “Modeling the Effects of Injector Nozzle Geometry on Diesel Sprays,” SAE Technical Paper 1999-01-0912, 1999, doi:10.4271/1999-01-0912.
Ramamurthi, K., Nandakumar, K., Characteristics of flow through small sharp-edged cylindrical orifices, Flow Measurement and Instrumentation, 10, pp. 133-143, 1999.
Payri, R., García, J.M., Salvador, F.J., Gimeno, J., Using spray momentum flux measurements to understand the influence of diesel nozzle geometry on spray characteristics, Fuel, 84, pp. 551-561, 2005.
Postrioti, L., Grimaldi, C.N., Ubertini, S., Bella, G., “Study of the Influence of the Injection System in a Multi-dimensional Spray Simulation,” SAE Technical Paper 2005-24-088, 2005, doi:10.4271/2005-24-088.
Foschini, L., Analisi numerica 1D di un sistema di iniezione Common Rail Bosch, MS Thesis, University of Perugia, 2004.
Gatti, L., Analisi CFD-3D in regime transitorio della cavitazione in un iniettore diesel, MS Thesis, University of Perugia, 2009.

[NewsW]

Numerical Study of Thermal-Fluid-Interaction in a Diesel Fuel Injector
Number: 2008-01-2760

Published: 2008-04-01





Publisher: SAE International

Language: English
DOI: 10.4271/2008-01-2760
Author(s): R. Leuthel - University of the Federal Armed Forces; M. Pfitzner - University of the Federal Armed Forces; M. Frobenius - AVL Germany GmbH
Citation:
Leuthel, R., Pfitzner, M., and Frobenius, M., "Numerical Study of Thermal-Fluid-Interaction in a Diesel Fuel Injector," SAE Technical Paper 2008-01-2760, 2008, doi:10.4271/2008-01-2760.


Citation

Abstract:

There is experimental evidence that flow optimised Diesel injectors using ks-nozzles show an increased tendency towards the formation of deposits. These deposits reduce spray quality and have an adverse effect on soot emissions and engine performance. Since deposit formation is known to be caused by locally high temperatures, the thermal behaviour of Diesel injectors using cylindrical and ks-nozzle was investigated. For this reason a coupled fluid -thermal analysis for a Diesel fuel injector was performed using a 3D-CFD-Code for both the solid structures and the fluid domain. As a first focus of this work the thermal conditions at the injector tip have been extracted from a complete in-cylinder-flow-simulation and a subsequent sensitivity study at the injector tip showed the influence of boundary conditions and configuration changes. The second focus of our work was the calculation of the temperature increase of the fuel remaining in the nozzle holes and in the sac hole between two injections. To this end, a coupled simulation over two working cycles has been performed for both cylindrical and ks-nozzles to investigate the heating and vaporisation of fuel within the injector in the time period between injections, which may contribute to the formation on deposits in injector nozzles

[NewsW]

Diesel Fuel Injector Deposits ---

From Fuel additives, not combustion chamber:

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Investigation into the Formation and Prevention of Internal Diesel Injector Deposits
Number: 2008-01-0926

Published: 2008-04-14


Publisher: SAE International

Language: English
DOI: 10.4271/2008-01-0926
Author(s): Jörg Ullmann - Robert Bosch GmbH; Marion Geduldig - Robert Bosch GmbH; Heinz Stutzenberger - Robert Bosch GmbH; Rinaldo Caprotti - Infineum; Graham Balfour - Infineum
Citation:
Ullmann, J., Geduldig, M., Stutzenberger, H., Caprotti, R. et al., "Investigation into the Formation and Prevention of Internal Diesel Injector Deposits," SAE Technical Paper 2008-01-0926, 2008, doi:10.4271/2008-01-0926.



Abstract:

High precision high pressure diesel common rail fuel injection systems play a key role in emission control, fuel consumption and driving performance.

Deposits have been observed on internal injector components, for example in the armature assembly, in the slots of the piston and on the nozzle needle. The brownish to colourless deposits can adversely impact driveability and result in non-compliance with the Euro 4 or Euro 5 emission limits.

The deposits have been extensively studied to understand their composition and their formation mechanism. Due to the location of these deposits, the influence of combustion gas can be completely ruled out. In fact, their formation can be explained by interactions of certain diesel fuel additives, including di- and mono-fatty acids. This paper describes the methodology used and the data generated that support the proposed mechanisms. Moreover, approaches to avoid such interactions are discussed.

[45Ricochet]

blackeyed1 wrote:
I think I'll bring this stuff up to my high school buddy that used to be a GM engineer. He's like you guys that really get into high tech stuff. Most of this I haven't a clue what you are talking about but we all learn things by reading. 39 pages! Amazing!

The amazing part is about 40% is one poster :B
I thought I clicked onto the Science channel or something. No offense Ben :W
Sure wish the GOP would get to a 2 man discussion, err, ahhh forget that part.

[NewsW]

Now that you mentioned that... yes.. it makes its own humidity... and yes.. ford also patented a fuel cooler.