Abstract: The present invention provides for a system for controlling NOx emissions based on the calculation of an error given by the difference between a first measured value obtained from a NOx sensor (7) and a second one estimated from a NOx estimation. Said sensor (7) can be used in an adaptation loop, where an open-loop or closed-loop EGR control system is adapted such that the expected NOx emissions (from the EGR controller) match the ones measured with the NOx sensor under steady-state conditions.

Abstract: The present invention relates to a dosing module (1) for dosing an urea-based reducing agent into a exhaust gas stream of combustion engine and addressed to an after-treatment system, (30) e.g. SCR or SCRT system. The module (1) comprises an housing (20) which develops along a longitudinal axis (X) and an inlet opening (19) for conveying the exhaust gas. Dosage means (55) are provided for dosing the reducing agent. According to the invention, the inlet opening is annular and inclined with respect to the axis (X) of the housing (20) so as to generate an exhaust gas inlet jet (AJ). Moreover the dosage means are designed so as to generate, inside the housing (20), an urea-based reducing agent spray (UWS) coaxial to the axis (X) of the housing (20).

Abstract: The present invention provides for a method for dosing an urea-based reducing agent into a exhaust gas stream generated from a combustion engine and addressed to an aftertreatment system, e.g. SCR or SCRT system. According to the method of the invention the gas exhaust stream is conveyed into a dosing housing which develops along a longitudinal axis. In particular the gas is conveyed by generating an annular inlet jet inclined with respect of said axis. The urea-based reducing agent is injected by generating, inside the housing, an urea-based reducing agent spray which is preferably coaxial to said axis of the housing.

Abstract: The invention relates to a mechanical variable valve actuation (VVA) system for the control and actuation of the valves of an internal combustion engine. The system according to the present invention realizes the control of the valve lift by means of a fixed pivot part for an oscillating rocker suitable to actuate the valve, the oscillating rocker being actuated by means of an eccentric control element.

Abstract: A turbocompound engine has an internal combustion engine with a first recuperation turbine positioned on an exhaust line of the engine. The first turbine provides mechanical power to the engine. Heat from an exhaust line of the first turbine is transferred to a heat recovery system. A second turbine is operated by the heat within the heat recovery system and provides mechanical power to the engine.

Abstract: A method for evaluation of the true fuel flow rate supplied to a test vehicle engine under various operation conditions is disclosed. The method includes the steps of determining the load applied to the tested engine by way of a deceleration test and determining the true fuel flow rate through the use of a reference engine of the same type as the tested engine, subjected to the load applied to the tested engine.

Abstract: Variable geometry turbine, in particular a gas turbine, comprising a housing (2, 22), a turbine rotor (4), a fluid inlet scroll (1) that surrounds the turbine rotor, a vaned nozzle interposed between the inlet scroll and the turbine rotor conceived to accelerate the flow of fluid, the nozzle comprising an axially adjustable ring (5, 25) conceived to vary the nozzle gap (3, 23) and having a wall (19) delimiting the nozzle gap, the wall having balance holes (6, 26, 26?) connecting the nozzle gap with a chamber (12) delimited by the housing and the ring, characterised in that the edges (16), formed by the holes with the surface (18) of the wall facing the nozzle gap, are rounded in the portion (17, 17?) located downstream the holes with respect to the fluid flow. Turbocharger and supercharged engine comprising the engine.

Abstract: A variable geometry turbine, particularly for a supercharger turbocompressor of an internal combustion engine, comprising an outer housing forming a spiral inlet channel for an operating fluid, a rotor supported in a rotary manner in the housing, and an annular vaned nozzle of variable geometry interposed radially between the channel and the rotor and comprising a control member moving axially in order to control of the flow of the operating fluid from the channel to the rotor, the control member being formed as an annular piston of a fluid actuator actuated directly by means of a control pressure.

Abstract: A variable geometry turbine, particularly for a supercharger turbocompressor of an internal combustion engine, comprising an outer housing forming a spiral inlet channel for an operating fluid, a rotor supported in a rotary manner in the housing, and an annular vaned nozzle of variable geometry interposed radially between the channel and the rotor; the nozzle comprises a pair of vaned rings facing one another and provided with respective pluralities of vanes tapered substantially as wedges and adapted to penetrate one another, one of which can move axially with respect to the other in order to define a variable throat section between these vaned rings.

Abstract: A turbocompound internal combustion engine having a turbocharger with a variable-geometry turbine; and an auxiliary turbine, which is located downstream from the turbine of the turbocharger, provides for recovering energy from the exhaust gas, and is connected mechanically to the drive shaft of the engine via a transmission; a control device compares the rotation speed of the auxiliary turbine, detected by means of a sensor, with a range of permissible speeds calculated on the basis of the speed of the drive shaft, and controls fuel supply to the engine and the geometry of the variable-geometry turbine to maintain the speed of the auxiliary turbine within predetermined limits in the event of a fault on the transmission.

Abstract: An engine-turbocharger unit for a vehicle, in particular an industrial vehicle, having an internal combustion engine; a decompression brake device; and a turbocharger in turn having a variable-geometry turbine driven by the exhaust gas from the engine, and a compressor driven by the turbine and connected at the outlet to an intake manifold of the engine; the unit also has a throttling device located on the outlet side of the turbine and settable between a fully-open attitude and a closed attitude; the variable-geometry turbine and the throttling device are jointly controlled, thereby allowing independent control of the exhaust manifold pressure of the combustion engine and of the expansion ratio of the turbine.