Abstract:
Method to control the combustion of a compression ignition engine (1) with reactivity control through the injection temperature; the control method provides for the steps of: establishing a quantity (Q) of fuel to be injected into a cylinder (2); injecting a first fraction (F1) of the quantity (Q) of fuel fed by a first feed system without active heating devices, preferably equal to at least 70% of the quantity (Q) of fuel, at least partially during the intake and/or compression stroke; injecting a second fraction (F2) of the quantity (Q) of fuel fed by a second feed system provided with at least one active heating device (12; 13), and equal to the remaining fraction of the quantity (Q) of fuel, into the cylinder (2) at the end of the compression stroke and preferably at no more than 60° from the top dead centre (PMS); and heating the second fraction (F2) of the quantity (Q) of fuel to an injection temperature (T) of over 100°C, before injecting the second fraction (F2) of the quantity (Q) of fuel.
Abstract:
Systems and methods for controlling fuelling of dual fuel internal combustion engines are disclosed. The control techniques maximize the substitution rate of gaseous fuel for the liquid fuel by determining a target fuelling amount for the liquid fuel and then regulating an actual fuelling amount of the liquid fuel in response to engine speed and power variations and by modulating the flow rate of the gaseous fuel to the engine.
Abstract:
In the method for operating a piston engine, the engine is operated in a first operating mode by introducing main fuel into the cylinders (1) after pilot fuel injection has started, and in a second operating mode by introducing the main fuel into the cylinders (1) before the pilot fuel. One or more indicators of auto- ignition and/or a risk of auto-ignition of the main fuel are monitored and com- pared to predetermined ranges indicating auto-ignition or the risk of auto- ignition. If one or more of the monitored indicators is within the predetermined range, the engine is operated in the first operating mode, and if none of the monitored values is within the predetermined range, the engine is operated in the second operating mode.
Abstract:
Vorgeschlagen wird ein Verfahren zur Steuerung und Regelung einer Brennkraftmaschine nach dem HCCI-Brennverfahren, bei dem ein erster Kraftstoff in einem Grundgemisch über einen Pilotkraftstoff entzündet wird und bei dem die Kraftstoffmassen des ersten Kraftstoffs und des Pilotkraftstoffs zu Darstellung eines [Betriebspunkts der Brennkraftmaschine verändert werden. Die Erfindung ist dadurch gekennzeichnet, das eine Soll-Verbrennungsenergie (VE(SL)) in Abhängigkeit einer Leistungsanforderung berechnet wird und anhand der Soll-Verbrennungsenergie (VE(SL)) über einen Aufteilungsfaktor (CHI) die Kraftstoffmasse des ersten Kraftstoffs und die Kraftstoffmasse des Pilotkraftstoffs festgelegt werden, wobei der Aufteilungsfaktor (CHI) über einen Verbrennungslageregler (18) in Abhängigkeit einer Ist-Verbrennungslage (VL(IST)) zu einer Soll-Verbrennungslage (VL(SL)) berechnet wird.
Abstract:
The invention relates to a method of operating an internal combustion engine by combusting gaseous fuel comprising the steps of feeding gaseous fuel and combustion air to the combustion chamber of the engine, compressing the mixture of the combustion air and the gaseous fuel in the combustion chamber, feeding the mixture of the combustion air and the gaseous fuel from the combustion chamber to a first and a second pre-chamber arranged in flow communication with the combustion chamber, igniting the mixture of the combustion air and the gaseous fuel in the first pre-chamber at a first moment, and igniting said mixture in the second pre-chamber at a second moment, after the first moment, ignition being accomplished by means of injecting liquid fuel into a pre-chamber and igniting the liquid fuel by compression ignition.
Abstract:
A compression ignition engine uses two or more fuel charges having two or more reactivities to control the timing and duration of combustion. In a preferred implementation, a lower-reactivity fuel charge is injected or otherwise introduced into the combustion chamber, preferably sufficiently early that it becomes at least substantially homogeneously dispersed within the chamber before a subsequent injection is made. One or more subsequent injections of higher-reactivity fuel charges are then made, and these preferably distribute the higher-reactivity matter within the lower- reactivity chamber space such that combustion begins in the higher-reactivity regions, and with the lower-reactivity regions following thereafter. By appropriately choosing the reactivities of the charges, their relative amounts, and their timing, combustion can be tailored to achieve optimal power output (and thus fuel efficiency), at controlled temperatures (and thus controlled NOx), and with controlled equivalence ratios (and thus controlled soot).
Abstract:
Bei einem Verfahren zum Betrieb einer Brennkraftmaschine (1), insbesondere eines Ottomotors mit Benzindirekteinspritzung, in kontrollierter Selbstzündung, wobei die Brennkraftmaschine (1) einen Brennraum, mindestens ein Einlassventil (27) und mindestens ein Auslassventil (28), deren Öffnungszeiten veränderbar sind, umfasst und ein Kraftstoff-Luft-Abgas-Gemisch in einen Brennraum (26) eingebracht und in einem Verdichtungstakt (V) verdichtet wird, wobei das Kraftstoff-Luft-Gemisch gegen Ende des Verdichtungstaktes (V) selbstzündet, wird eine kontrollierte Selbstzündung in weiten Lastbereichen ermöglicht, indem die Öffnungszeiten des Einlassventils (27) und des Auslassventils (28) lastabhängig verändert werden.
Abstract:
A method of mixed mode operation of an internal combustion engine (10) includes the steps of controlling a homogeneous charge combustion event timing in a given engine cycle, and controlling a conventional charge injection event to be at least a predetermined time after the homogeneous charge combustion event. An internal combustion engine (10) is provided, including an electronic controller (30) having a computer readable medium with a combustion timing control algorithm recorded thereon, the control algorithm including means for controlling a homogeneous charge combustion event timing and means for controlling a conventional injection event timing to be at least a predetermined time from the homogeneous charge combustion event.