Intake Valve Deposits Research Articles

SuperButol™ – A novel high-octane gasoline blending component

Higher fuel anti-knock quality will be required as spark ignition engines are designed for higher efficiency in the future. This paper introduces a new high-octane gasoline blending component made from low value mixed butenes using a new process. The component named SuperButol™ is mainly a mixture of butanol isomers (∼93%) with small amounts of diisobutylenes (∼5%) and di-sec-butyl ether (∼2%). The manufacturing process is described in brief and the results of blending this product on gasoline properties and comparison with other high-octane components such as MTBE and ethanol are presented.SuperButol™ has slightly lower blending RON compared to MTBE but has lower blending vapor pressure and higher energy content compared to ethanol. SuperButol™ has insignificant effect on key gasoline specifications, namely, potential and actual gum, oxidation stability, intake valve deposits, port fuel injector fouling, haze formation and water extractability performance. Therefore, it is considered to be a viable and affordable gasoline component, which can help to meet future demands for high-octane gasoline. In addition, the process helps to optimize refinery operations by valorizing low-value products.

Formation of Intake Valve Deposits in Gasoline Direct Injection Engines

Formation of Intake Valve Deposits in Gasoline Direct Injection Engines

Effects of Gasoline and Ethanol Fuel Corrosion Inhibitors on Powertrain Intake Valve Deposits

Effects of Gasoline and Ethanol Fuel Corrosion Inhibitors on Powertrain Intake Valve Deposits

Effects of fuel additives on the microstructure of combustion engine deposits

The microstructure of spark-ignition (SI) engine deposits produced from fuels with two commonly used gasoline additives, polyether amine and polybutene amine, were studied by gas adsorption technique and Raman spectroscopy. The lateral sizes of graphitic crystallites were found to increase upon addition of the additives. The surface areas of the deposits were evaluated using the BET and DR theories. Density functional theory was used to evaluate pore size distribution. The majority of the internal surface area of the deposits is due to narrow pores of widths of about 0.5 nm. The surface area of the deposits decreases with increased concentration of the additives, and this process is more efficient for polybutene amines than polyether amines. The structure of the deposits removed from the combustion chamber’s cylinder heads is more porous than that of piston top deposits. Likewise, intake valve deposits were seen to be less porous than combustion chamber deposits.

A study on the deposit formation in the cylinder and intake valve of a S. I. Engine

A spark ignition engine with port fuel injection (P.F.I.) system was used to accumulate cylinder head deposit (C.H.D.), intake valve deposit (I.V.D.), and piston top deposit (P.T.D.) on an engine dynamometer. In this study, the effect of base gasoline on I.V.D. was examined. The deposit forming tendency and the influence of the fuel component for decreasing deposits have been experimentally examined. The amount of I.V.D. has been observed to increase linearly with the engine operating time. It is also observed that the amount of valve deposit with newly blended gasoline is less than that with base gasoline.

The effects of different gasoline blends doped with used engine oil on the forming tendency of simulated intake—valve deposits

The effects of gasoline composition doped with a trace amount of used engine oil on the formation of simulated intake valve deposit have been investigated. Studies were performed using a bench top simulator. Oxygenated gasoline has been found to exhibit a high deposit-forming tendency. In addition to the amount, the nature of the deposit formed also depends on the type of fuel used. For oxygenated fuel, a dry carbonaceous deposit is usually formed instead of the polymeric deposit that is commonly obtained from non-oxygenated fuel.

An investigation of the relationship between used engine oil properties and simulated intake valve deposits

The degradation of engine oil and its influence on the formation of intake valve deposits is being discussed in this paper. Degraded samples of oil were prepared using a stationary engine testbed while deposition studies were performed using a bench top simulator. The degree of degradation, as indicated by the amount of polymeric, oxidized and oxidative products, increases as the engine oil is used over a period of time. The rate of degradation, however, varies depending on the quality of base oil and the type of additives used. It was observed that the degraded oil played an important role in the formation of inlet valve deposits.

Influences of lubricant composition and lead content in gasoline on intake valve deposit.

Lubricant composition and lead in gasoline were chosen as two major factors for the formation of intake valve deposit during operation. Several engine tests and a new laboratory test were employed to evaluate the effects of these two factors on the composition as well as the amount of deposits formed.The modified Panel-Coking test, which was developed in the present work, was found to be very suitable for studying intake valve deposit, and the results obtained from this method correlated well with those from engine tests.Although both lubricant composition and lead content of a fuel contribute a great deal to the formation of deposits as reported by several workers, the amount of deposits on the intake valve was found to be dependent primarily on lubricant composition, especially on the concentration of the V. I. improver used and far less on the lead content of the fuel. Also the modified Panel-Coking test suggested some critical temperature-ranges for accumulation of intake valve deposits; for example, 280-330°C for 10W-50, 320-370°C for 10W-30, 350°C<for SAE30 oil.