Engine injection systems

Moreover, European regulations in 2005 restricted the sulfur content in diesel fuel to SOmgkg. Sulfur organic compounds are known to provide diesel fuel with a lubricity that will disappear as the regulations take effect. Addition of biodiesel at a level of 1-2% to diesel blends has the effect of restoring lubricity through an antiwear action on engine injection systems, which is specific for polar molecules. 

Water can contribute to filter blocking and cause corrosion of the injection system components. In addition to clogging of the filters, sediment can cause wear and create deposits both in the injection system and in the engine itself. Thus one of the most important characteristics of a diesel fuel, the water and sediment content (ASTM D-1796, IP 75), is the result of handling and storage practices from the time the fuel leaves the refinery until the time it is delivered to the engine injection system. 

Other heavy fuel contaminants are metals (vanadium, nickel, sodium) coming from the crude oil itself or metallic salts (aluminum silicates) coming from catalysts in conversion steps. The aluminum silicates should not exceed 300 ppm (30 ppm of aluminum), for these materials exert a strong abrasive action on the engine cylinders and injection systems. They can however be eliminated partially by centrifuging and filtration. 

B. M. Bertilsson, "Regulated and Unregulated Emissions from an Alcohol-Pueled Diesel Engine with Two Separate Euel Injection Systems," 5th Int. Symp. on AlcoholEuel Technology (Auckland, New Zealand, May 13—18, 1982) Vol. 3. 

M. Nuti, M Variable Timing Electronically Controlled High Pressure Injection System for 2S S.I Engines, SAE 900799, Society of Automotive Engineers, Warrendale, Pa., 1990. 

Water injection, or steam injection systems, are being used extensively to augment power. Corrosion problems in the compressor diffuser and combustor have not been found to be major problems. The increase in work and efficiency with a reduction in NO makes the process very attractive. Split-shaft cycles are attractive for use in variable-speed mechanical drives. The off-design characteristics of such an engine are high efficiency and high torque at low speeds. 

Manifold barriers confine the radioactivity to the 1) ceramic fuel pellet 2) clad 3) cooling water, as demonstrated by the TMI-2 accident 4) primary cooling loop 5) containment and 6) separation from the public by siting. Further protection is provided by engineered safety systems pressurizers, depressurization, low pressure injection, high pressure injection and residmil heat removal systems. 

All diesel fuels tend to contain trace water, expressed in parts per million (ppm). With the veiy high fuel injection pressures now used in electronically controlled diesel engine, fuel-filter/water separators are widely used, since water allowed to circulate freely through the injection system can result in seizure of components and erosion of injector orifice holes, and in extreme cases the high compressibility factor of water can blow the tip off of the fuel injector. 

The first engines invented by Rudolf Diesel ran on groundnut oil, but because of the advent of relatively cheap oil this type of biodiesel never became commercially viable. Since about 1930 the diesel engine has been refined and fine tuned to run on the diesel fraction of crude oil, which consists mainly of saturated hydrocarbons. For this reason the modem diesel engine cannot run satisfactorily on a pure vegetable oil feedstock because of problems of high viscosity, deposit formation in the injection system and poor cold-start properties. Today, however, environmental... 

Brown RQ, Mount A, Burg KJ (2005) Evaluation of polymer scaffolds to be used in a composite injectable system for intervertebral disc tissue engineering. J Biomed Mater Res A 74(l) 32-39... 

Another important application of plain-orifice atomizers is jet engine afterburner injectors. The fuel injection system typically consists of one or more circular manifolds supported by struts in a jet pipe. The fuel is supplied to the manifold by feed pipes in the support struts and sprayed into the combustion zone through the orifices in the manifold. Increasing the number of orifices and/or using a ringlike manifold may promote uniform distribution of liquid. To reduce the risk of blockage of orifices, a minimum orifice size of 0.5 mm is usually regarded as practical for kerosene-type fuels. 

The first requirement in developing the ACC was to control air-fuel mixtures, and in contemporary cars this is maintained at precisely the 19 1 stoichiometric ratio for aU engine loads, using an exhaust O2 sensor that controls the fuel injection system. The composition and location of the catalyst within the reactor are also crucial to proper design. 

There is much concern about the emissions which result when fuel sulfur combusts (i.e., sulfur oxides). These gaseous products further react to form environmental pollutants such as sulfuric acid and metal sulfates. Active sulfur and certain sulfur compounds can corrode injection systems and contribute to combustion chamber deposits. Under low-temperature operating conditions, moisture can condense within the engine. Sulfur compounds can then combine with water to form corrosive acidic compounds. 

High-pressure diesel fuel injection systems contain expensive and sophisticated components. The high-pressure pump and injector are the key components to ensuring proper fuel management within the diesel engine. Clearances and tolerances between moving parts of the fuel pump are quite fine. Even a small amount of deposit, contamination, or corrosion can significantly alter the efficient performance of the fuel injection system. 

Deposit control additives or detergents are added to diesel fuel to help prevent the formation and accumulation of deposits on fuel injection system parts. Detergents provide the following performance function in the diesel engine ... 

Fuel, usually gasoline or diesel fuel, is transferred to the engine from the fuel tank (or tanks) by this pump, which is either a mechanically driven device or, as is now more common, electrically driven. The fuel pump delivers fuel to a carburetor (gasoline) or fuel injection system (diesel and newer gasoline engines), which distribute the fuel under pressure in a spray to the proper cylinder. Many devices that were formerly mechanically driven are now replaced by computer-controlled devices. 

To study the effectiveness of the oxygen injection system, as well as to investigate other water-quality issues, the Waterways Experiment Station (WES), U.S. Army Corps of Engineers, conducted extensive studies in both Lake RBR and Lake Thurmond. These ongoing studies, which began prior to creation of the impoundment, provide a detailed picture of the course of events since impoundment. Reports containing these data (54) form a valuable basis for other studies. 

The vast majority of propane fuel systems used on light-duty vehicles to date have been of the mechanical-control type that meter propane in proportion to the amount of air used by the engine (air-valve and venturi-type mixers ). While these systems work well, their capabilities have been overshadowed by gasoline fuel injection systems and often lag behind gasoline systems in terms of acceleration, driveability, and cold-start performance. Chrysler Canada and one European equipment manufacturer offer liquid propane injection systems that are direct analogs to gasoline port fuel injection systems. These systems should have inherent performance advantages compared to the vaporized propane fuel systems. 

The viscosity of methyl esters is similar to diesel fuel, and in most cases higher than diesel fuel. This could potentially have an impact on the quantity of fuel injected by diesel engine fuel injection systems, but it is not likely to cause significant changes. 

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