The performance of a variable compression ratio compression ignition engine operating on ethanol-diesel fuel blends has been evaluated experimentally. We aimed to determine the optimum percentage of ethanol and the compression ratio of the engine that give the best performance and efficiency at the same time. The engine was operated with ethanol-diesel fuel blends having 2, 4, and 6% ethanol on a volume basis as well as on diesel fuel alone. The experiments were performed for the compression ratios of 19, 21, and 23. Experimental results indicate that the addition of 4% ethanol to diesel fuel increases power output and efficiency of the engine while it decreases specific fuel consumption for various compression ratios. The best efficiency was attained at the compression ratio of 21 with an increment ratio over 3.5%.

The Effects of Diesel-Ethanol Blends on Diesel Engine Performance

Methods and systems are provided for improving fuel usage while addressing knock by adjusting the use of spark retard and direct injection of a knock control fluid based on engine operating conditions and the composition of the injected fluid. One or more engine parameters, such as EGR, VCT, boost, throttle position, and CMCV, are coordinated with the direct injection to reduce torque and EGR transients.

Method and system for controlling fuel usage

Understanding octane number evolution for enabling alternative low RON refinery streams and octane boosters as transportation fuels

Laboratory and road tests showed methanol to be an effective octane booster Adding 10% methanol to unleaded gasoline raised the road octane 2 to 3 numbers However, sinificant deterioration in driveability tests occurred because of methanol's leaning effect The water sensitivity of methanol/gasoline requires a separate fuel distribution system Fuel storage in a vehicle must be protected from water absorption Corrosion and degradation problems occur in the vehicle fuel system where methanol/gasoline mixtures contact lead, magnesium, aluminum, and some plastics Methanol burned more efficiently under lean conditions than gasoline However, the cold start problems require a separate starting fuel Methanol is not a useful fuel additive for existing unmodified cars Methanol could be used effectively in special vehicles designed to handle the corrosion, water absorption, and vaporization characteristics The cost of manufacture and distribution in a separate system that overcomes the water sensitivity problem will determine the extent of methanol's use as a vehicular fuel

Methanol as a motor fuel or a gasoline blending component

Methanol as a Fuel: A Review with Bibliography

Methanol's potential as a gasoline extender has been evaluated, with data being obtained in the areas of fuel economy, exhaust emissions, and driveability. The results of tests with three cars, having carburetion spanning the range normally encountered in the existing car population, showed that methanol's effect on fuel economy and emissions could be directly related to its leaning effect on carburetion. The data suggest that any benefits in these two areas would only be significant for older, rich-operating cars. A 13-car driveability study indicated that the large increase in fuel volatility which occurs with the addition of methanol to gasoline could pose serious problems. A marked increase in vapor locking tendency was observed when no front-end volatility adjustments were made to the methanol blends. Stretchiness, a lack of expected response to throttle movement, was also found with the methanol blends. This operational characteristic, being related to excessively lean operation, was more pronounced with the newer cars tested. Phase separation is also a potential problem with methanol-gasoline blends. Data are presented which show the effect of including higher molecular weight alcohols along with the methanol. Phase separation still occurred in the presence of less than 1% water. Taken as a whole,more » the data suggest that, if it becomes available in large quantities, the use of methanol in applications other than in motor gasoline would be preferred.« less

Eric E. Wigg

Papers

Methanol as a gasoline extender: fuel economy, emissions, and high temperature driveability