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Novel SCT System for Two-Stroke Engine

OTT case 11-003 | US Patent 8,997,701

Advantages of two-stroke engines over comparable four-stroke engines are that they are less expensive to manufacture and easier to maintain. Current disadvantages of the two-stroke engine are poor fuel economy, hydrocarbon emission levels and often high sound emissions. It is not unusual to both see and smell the exhaust emitted from such engines. 

Researchers at the university's National Institute for Advanced Transportation (NIATT) have designed and fabricated a reciprocating valve SCT that rotates continuously at the same speed as the engine. The valve face can be timed as to cause minimal restrictions to the exhaust flow as it exits the cylinder. During the intake/compression phase of the engine cycle, the valve face will obstruct the exhaust port. This prevents fresh air and fuel charge from exiting the cylinder.

Initial prototype testing shows a 20 to 35 percent increase in torque and horsepower for the same fuel at cruising conditions (25 percent throttle).

SCT for two stroke engine
SCT for Two-Stroke Engine, OTT case 11-003