Performance Potential of an Ethanol Fueled Turbocharged Direct Injection Otto Engine

The search for better energetic efficiency of the flexible fuel engines will guide the next design changes in this technology. The use of direct injection and the downsizing of volumetric displacement compensated by supercharging is a possible solution to reduce the fuel consumption. The direct injection brings the thermodynamic benefits of the charge cooling; the reduced displacement reduces the pumping work in partial loads and engine friction, while the supercharging allows the performance of a bigger engine. The combination of these technologies with hydrated ethanol (E100 or AEHC) represents a performance and CO₂ reduction opportunity, but also a challenge in terms of cold start and durability.

The objective of this study is to evaluate and compare the behavior and the potential in full load conditions of an engine equipped with direct fuel injection and turbocharger, using Brazilian Hydrated Bioethanol (called as E100) and Brazilian gasoline (called E22). Instead of using E100 to raise the engine performance (torque and power), with the adjustment of manifold pressure, spark advance and air-to-fuel rate, was possible to take the physical and chemical characteristics of E100 to increase the engine efficiency with same performance, without compromising the main engine parameters for durability.