Fuel Delivery System

A fuel cell has two basic elements a fuel delivery system and an electro-chemical cell that converts the delivered fuel into useful electricity. It is this unique combination that enables fuel cells to potentially offer the best features of both heat engines and batteries. Like batteries, the cell generates a dc electric output and is quiet, clean, and shape-flexible, and may be manufactured using similar plate and filmrolling processes. By contrast, the fuel delivery system ensures that fuel cells, like heat engines, can be... 

In this relatively simple example, a contaminant material had been noticed on the surface of a fuel delivery system component made by an automotive manufacturer. The identity of the contaminant, descriptively named "black goo", was required so that the source could be determined and the problem eliminated in the future. 

Case study B5 Automotive components, fuel delivery system module... 

An automotive component supplier manufacturing a fuel delivery system module noticed contamination, appearing as whitish-yellow particles, in one unit. Some initial testing included both FTIR spectroscopy and SEM. However, additional testing was requested in order to independently and more accurately determine the source of the contamination. Preliminary testing indicated that the... 

In order to more accurately identify the contaminant, and to determine if the fuel delivery system module filter was the source, both materials were analyzed using 1H NMR spectroscopy Samples were dissolved in a 60 40 mixture of deuterated chloroform/triflouroethanol. It should be noted that the amount of contaminant available for analysis was quite small, so for this sample, the NMR spectral acquisition time was set to 1 h in order to record a spectrum of adequate signal-to-noise ratio. 

Figure 31 shows the NMR spectrum recorded from the polyamide filter, and it is a high-quality match with polyamide 6,6, the structure of which is shown on the figure. Figure 32 compares the NMR spectrum for the filter along with that of the contaminant. Although the contaminant spectrum has more noise due to the low level of material available, it is evident that the spectrum acquired from the contaminant has peaks identical to those of the filter. Therefore, it can be concluded that the contaminant is polyamide 6,6, and the likely source was the fuel delivery system module filter. 

Figure 32 Stacked H NMR spectra of the contaminant (top) and fuel delivery system module filter (bottom) samples. 

Premature ignition can be reduced or eliminated by redesigning the fuel delivery system, which can be categorized into three types central-, port-, and direct injection. Central and port fuel injections form the fuel-air mixture during the intake stroke. In the case of central injection (or a carburetor), the injection is at the inlet of the air intake manifold. In the case of port injection, fuel is injected at the inlet port. Direct injection is technologically sophisticated and involves forming the fuel-air mixture inside the combustion cylinder after the air intake valve has closed [27-36]. 

The road to hydrogen vehicles and a hydrogen fueling delivery system may take many paths. Today, it may seem unlikely that market forces alone will result in the installation of thousands of hydrogen fueling stations across the country. But, this is exactly what happened with our pres-... 

Detergent Additives. Diesel engine deposits are most troublesome in the fuel delivery system, ie, the fuel pump and both fuel side and combustion side of the injectors. Small clearances and high pressures mean that even small amounts of deposits have the potential to cause maldistribution and poor atomization in the combustion chamber. The same types of additives used in gasoline are used in diesel fuel. Low molecular weight amines can also provide some corrosion inhibition as well as some color stabilization. Whereas deteigents have been shown to be effective in certain tests, the benefit in widespread use is not fully agreed upon (77). 

Evaporative Emission. Fumes emitted from stored fuel or fuel left in the fuel delivery system are also regulated by U.S. EPA standards. Gasoline consists of a variety of hydrocarbons ranging from high volatility butane (C-4) to lower volatility C-8 to C-10 hydrocarbons. The high volatility HCs are necessary for cold start, and are especially necessary for temperatures below which choking is needed to start the engine. Stored fuel and fuel left in the fuel system evaporates into the atmosphere. 

Nilsson, D., SHAM - A Simulation Model For Designing Straw Fuel Delivery Systems. Part 2 Model Applications, Biomass and Bioenergy, 16, 39-50 (1999). 

Chandler, J. E., and Zechman, J. A. 2000. Low Temperature Operability Limits of Late Model Heavy Duty Diesel Trucks and the Effect Operability Additives and Changes to the Fuel Delivery System Have on Low Temperature Performance. In SAE Spec. Publ. SP-1563, Gasoline and Diesel Fuel Performance and Additives 2000. Warrendale PA Society of Automotive Engineers (Paper No. 2001-01-2883). 

Gas turbine engines with a conventional natural gas combustion system or water injection combustion system can operate on H2 or H2-rich fuels with little or no modifications to the core injectors. Modifications to the fuel delivery system and injectors are required. The volumetric heating value of hydrogen is 10,787 kJ/N-m3 (274 Btu per standard cubic foot [scf]> as compared with 35,786 kJ/N-m3 (909 Btu/scf) for methane. In order to supply the required energy input rate to the gas turbine, approximately 3.32 times the volume of hydrogen fuel has to be injected into the primary zone of the combustor to provide the same heating value as that of natural gas fuel. 

In the original configuration, a malfimctioning of the fuel punqj did occur when switching from diesel to bio-oil and vice-versa. It was assumed that residues of die difTerent fuels mix and clog the punqi and fuel delivery system. In order to avoid this clogging problem, an alcohol fiiel is burnt immediately before switching over. After this modification a satisfactory and stable start-up of the combustion facility was achieved. 

A fire hazard can be defined as any fluid, product, piece of equipment, process, etc. that has the potential to cause or contribute to a fire. The fuel delivery system is a primary fire hazard because of the potential for a leak of the fuel into the surrounding environment or atmosphere which is almost always air. This is an immediate hazard because of the possibility of an uncontrolled fire or an explosion depending upon the size and location of the leak and the availability of an ignition source. 

Adapting or re-designing the fuel delivery system can be effective in reducing or eliminating pre-ignition. 

Hydrogen fuel delivery system can be broken down into three main types central injection (or carbureted ), port injection and direct injection. 

Central and port fuel delivery systems injection form the fuel-air mixture during the intake stroke. In the case of central injection or a carburetor, the injection is at the inlet of the air intake manifold. In the case of port injection, it is injected at the inlet port. 

The port injection fuel delivery system injects fuel directly into the intake manifold at each intake port, rather than drawing fuel in at a central point. Typically, the hydrogen is injected into the manifold after the beginning of the intake stroke. At this point conditions are much less severe and the probability for premature ignition is reduced. 

Fuel delivery systems include hydrogen (electrolyzers, bottles, pipelines, reformate and others), natural gas, propane, methanol, ethanol, anaerobic digester gas (ADG), diesel, bio-diesel, gasoline, landfill methane, and jet fuels... 

The fuel delivery system reported for pDAFC are similar to that used in larger DAFC and are summarized in Fig. 1.11 [57]. 

The real mieromachined parts of the micro fuel eell are generally the electrode plates and the fuel delivery system. The latter is often aehieved by mieroehannels. Nguyen et al made a review of the different designs for the fuel delivery systems [29], illustrated in... 

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