TY - Type of reference TI - Zero-dimensional turbulence modeling of a gasoline engine in a Miller cycle “Rightsizing” approach AU - Marcellin PERCEAU AU - Philippe GUIBERT AU - Stéphane GUILAIN AB - New environmental regulations are encouraging automakers to focus on over-expanded cycles and to set aside the classic Otto cycle. The Miller cycle is part of this family of cycles and can be applied to spark ignition engines easily by modifying the intake valve closing event. The engine expands more than the actual compression phase. The millerization of an engine is done by increasing the size of the engine and closing the intake valves in advance. The closing time is chosen to follow the same effective compression phase as the reference engine. This process is known as "rightsizing". This paper describes a zero-dimensional approach to estimate the benefits obtained by millerization of a reference engine. The model includes a heat transfer sub-model, based on the Woschni coefficient, as well as a friction sub-model that allows us to take into account the effect of an increase in size. Premature closure of the intake valves in the Miller cycle tends to reduce the intensity of aerodynamic movements within the cylinder, so the level of turbulence at the end of compression is reduced. This phenomenon increases combustion duration and affects efficiency. A K-k-ε turbulence model is used to estimate the intensity of turbulence at the end of compression. A relationship between combustion time and turbulence is proposed. For the reference engine, the benefits obtained by millerisation allow an increase of one efficiency point, corresponding to an efficiency improvement of about 3%. DO - 10.21494/ISTE.OP.2020.0577 JF - Entropy: Thermodynamics – Energy – Environment – Economy KW - ICE, Over-expanded cycle, Miller cycle, EIVC, 0D model, turbulence, flame radius, MCI, cycles à détente prolongée, cycle de Miller, EIVC, modèle 0D, turbulence, rayon de flamme, L1 - https://www.openscience.fr/IMG/pdf/iste_entropie20v1n3_2.pdf LA - en PB - ISTE OpenScience DA - 2020/12/3 SN - 2634-1476 TT - Modélisation 0D turbulente d’un moteur essence en vue de sa Millérisation UR - https://www.openscience.fr/Zero-dimensional-turbulence-modeling-of-a-gasoline-engine-in-a-Miller-cycle IS - Issue 3 VL - 1 ER -