valvetronic engine technology - IFET College of Engineering

• taking a modular approach in order todevelop specific engine variants;• ensuring a significant potential for ongoingdevelopment; and• providing the foundation for otherengine variants, i.e. communality withfutureengines.All of this led to the developmentof a fully variable valve drive system,BMW Valvetronic, helping tosignificantly reduce fuel consumptionwhile maintaining stochiometric drivingconditions with all the usual advantages.What Is Valvetronic?The Valvetronic engine is theworld's first engine without a throttlebutterfly. Valvetronic allows the engineto run without a throttle butterfly, thecylinder charge being determined underpart load as a function of the valveopeningperiod. The intake and outletcamshafts are driven by variable camadjustment, BMW’s Vanos technology.A further advantage of this concept isthat it allows worldwide use of theproven three-way catalyst for emissionsmanagement, thus meeting even thestrictest emissions standards in the US.Innovative technology wasessential in order to reach the demandingobjectives and functional requirementsdesired. However, at the same time, thisconcept demanded the utmost of theelectronic control and managementsystems in the engine.ConceptTaking nature as the role model: humanbeings also apply the ValvetronicprincipleA comparison with the humanbeing clearly explains how Valvetronicworks: Whenever we are required tomake a great effort, we human beingsbreathe in a deep and long process ofventilation. Whenever we need less air,we do not throttle the supply of air by,say, closing our nose or our mouth, butsimply breathe in a shorter, flatterprocess of ventilation. In a conventionalcombustion engine the throttle butterflyis basically comparable to a humanbeing keeping his nose or mouth at leastpartially closed. With its large valve lift(= deep, long ventilation) and shortvalve lift (= flat, short process ofventilation), Valvetronic, on the otherhand, is able to breathe in the same way