LiquidPiston’s X Engine is a non-Wankel rotary embodiment of the company’s innovative High Efficiency Hybrid Cycle (HEHC). The X Engine has few parts and three combustion events per rotor revolution, resulting in tremendous power density.
Darpa made this dream a reality, as they have succeeded in manufacturing an engine of just 1.8 kilograms with dimensions of a 5-inch smartphone, but the most attractive of all is the fact that you do not need pistons or oil for operation.
The creators of this engine Nikolai Shkolnik, a Russian mechanical engineer, and his son Alexander Shkolnik, a computer engineer, promised a 50% thermal efficiency.
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