Zero-dimensional turbulence modeling of a spark ignition engine in a Miller cycle « Dethrottling » approach using a variable valve timing system

The Miller cycle, using an early inlet valve closing, can significantly improve the overall efficiency of a spark ignition engine during partial load operations. shorter intake event minimizes need for throttling air and so reduces pumping losses. This method is known as “dethrottling”. Indeed, use variable lift system makes it possible to combine two different cam profiles in engine, one full operations loads. benefits this strategy, combined with timing (VVT) system, will be explored new 0D model. model take into account strong changes in-cylinder turbulence generated by VVT their effects on combustion. Efforts have been made reduce model's reliance external inputs. Therefore, analytical calculations quantities, such flame radius, favored. cycle lead indicated efficiencies around 44% addition up 1% over wide range