66results about How to "Combustion state is stable" patented technology

A fuel injection control device of an internal combustion engine includes fuel injection valve control means which calculates a basic fuel injection flow rate which becomes a target air-fuel ratio corresponding to an engine operation state and performs a driving control of the fuel injection valve, a fuel pressure sensor which detects a fuel pressure in the inside of the pressure storage chamber, a discharge amount control valve for controlling a fuel amount supplied to the pressure storage chamber from the high-pressure pump, and fuel pressure control means which controls the discharge amount control valve such that the fuel pressures in the inside of the pressure storage chamber agrees with a preset target fuel pressure, wherein the fuel injection control device includes fuel increase correction means which increases the basic fuel injection flow rate in a state that a rotational speed of the engine falls in a given preset rotational speed region where the minimum discharge flow rate of the high-pressure pump is expected to exceed zero and the fuel pressure in the inside of the pressure storage chamber is higher than the target fuel pressure.

An EGR control apparatus for an internal combustion engine, which is capable of properly controlling an inert gas amount of two types of EGR gas supplied to cylinders of the engine via two paths different from each other, thereby making it possible to ensure a stable combustion state, reduced exhaust emissions, and improve operability. The EGR control apparatus includes low-pressure and high-pressure EGR devices, and an ECU. The ECU controls the low-pressure and high-pressure EGR gas amounts according to engine speed and demanded torque, and when a combination of engine speed and demanded torque is in a predetermined region, the low-pressure and high-pressure EGR gas amounts are controlled such that inert gas in low-pressure EGR gas exceeds in amount inert gas in high-pressure EGR gas, and the former more exceeds the latter as engine speed is higher or demanded torque is larger.

An EGR control apparatus for an internal combustion engine, which is capable of accurately controlling an inert gas amount and an inert gas ratio of two types of EGR gas supplied to cylinders of the engine via two paths different from each other, thereby making it possible to ensure a stable combustion state and reduced exhaust emissions. The EGR control apparatus includes a low-pressure EGR device, a high-pressure EGR device, and an ECU. The ECU calculates a target low-pressure opening, calculates an estimated value of an in-cylinder low-pressure inert gas flow rate, which is the estimated value of an inert gas amount included in low-pressure EGR gas supplied to the cylinders via an intake passage, calculates a target high-pressure opening using the estimated value, and controls low-pressure and high-pressure EGR control valves, using the target low-pressure opening and the target high-pressure opening.

A fuel injection control device of an internal combustion engine includes fuel injection valve control means which calculates a basic fuel injection flow rate which becomes a target air-fuel ratio corresponding to an engine operation state and performs a driving control of the fuel injection valve, a fuel pressure sensor which detects a fuel pressure in the inside of the pressure storage chamber, a discharge amount control valve for controlling a fuel amount supplied to the pressure storage chamber from the high-pressure pump, and fuel pressure control means which controls the discharge amount control valve such that the fuel pressures in the inside of the pressure storage chamber agrees with a preset target fuel pressure, wherein the fuel injection control device includes fuel increase correction means which increases the basic fuel injection flow rate in a state that a rotational speed of the engine falls in a given preset rotational speed region where the minimum discharge flow rate of the high-pressure pump is expected to exceed zero and the fuel pressure in the inside of the pressure storage chamber is higher than the target fuel pressure.

Disclosed is a direct-injection spark-ignition engine designed to promote catalyst activation during cold engine operation. A fuel injection timing for a fuel injection period in an compression stroke (second fuel injection period F2) is set to allow a first fuel spray Ga injected from a first spray hole 40a to enter a cavity 34 in a piston crown surface 30, and allow a second fuel spray Gb to impinge against a region of the piston crown surface 30 located closer to an injector than the cavity 34, so as to cause the second fuel spray Gb having a lowered penetration force due to the impingement to be pulled toward the cavity 34 by a negative pressure generated in the cavity 34 as a result of passing of the first fuel spray Ga therethrough. The direct-injection spark-ignition engine can maximally hold an injected fuel spray around a spark plug to reliably stabilize a combustion state in a combustion mode for promoting catalyst activation during cold engine operation, while enhancing combustion efficiency in a homogenous combustion mode during normal engine operation.

A control system for an internal combustion engine, which is capable of properly performing air-fuel ratio control and ignition timing control according to an actual amount of intake air, even when reliability of the results of detection of the operating condition of a variable intake mechanism is low. The control system for controlling air-fuel ratio and ignition timing includes an ECU. The ECU calculates a target air-fuel ratio, calculates an air-fuel ratio correction coefficient, calculates a statistically processed value of an air-fuel ratio index value, calculates a corrected valve lift and a corrected cam phase, and determines a fuel injection amount according to the corrected valve lift, the corrected cam phase, and the air-fuel ratio correction coefficient.

A pressure pattern estimation device of a fuel injection controller of an engine estimates a pressure transition of fuel in a common rail. A surplus pressure range calculation device of the fuel injection controller calculates a surplus pressure range in which pressure pattern data provided by the pressure pattern estimation device exceeds a target common rail pressure. The fuel injection controller releases the common rail pressure to a lower-pressure side by operating a pressure reduction valve of the common rail to eliminate the surplus pressure range calculated by the surplus pressure range calculation device. Thus, the common rail pressure (injection pressure) during an injection period is smoothed.

A pressure pattern estimation device of a fuel injection controller of an engine estimates a pressure transition of fuel in a common rail. A surplus pressure range calculation device of the fuel injection controller calculates a surplus pressure range in which pressure pattern data provided by the pressure pattern estimation device exceeds a target common rail pressure. The fuel injection controller releases the common rail pressure to a lower-pressure side by operating a pressure reduction valve of the common rail to eliminate the surplus pressure range calculated by the surplus pressure range calculation device. Thus, the common rail pressure (injection pressure) during an injection period is smoothed.

The CFG is mixed with BFG by providing different delayed time when it is supplied into air reservoir (2), and thus the fluctuation ratio of CFG calorie is inhibited. The air current rate of BFG is controlled by feedback control according to gas calorie of mixed gas, and so the gas calorie of mixed gas is controlled.

The invention provides a combustor based on multi-zone combustion. The combustor comprises a combustor barrel body, a fuel gas injection system and a flame stabilizing disc, wherein, the fuel gas injection system and the flame stabilizing disc are arranged in the combustor barrel body; the fuel gas injection system comprises a central fuel gas pipe and a plurality of annular fuel gas spray pipes which are rotationally and symmetrically arranged by taking the central fuel gas pipe as the center; a plurality of central fuel gas through holes are formed in the tail end of a central fuel gas spraypipe; the fuel gas injection system further comprises a plurality of fuel gas branch pipes which are rotationally and symmetrically arranged by taking the central fuel gas pipe as the center, and oneends of the fuel gas branch pipes are in communication with the annular fuel gas spray pipes; first flow distribution through holes are formed in the fuel gas branch pipes in the radial direction ofthe combustor barrel body, and second flow distribution through holes are formed in the tail ends, away from the annular fuel gas spray pipes, of the fuel gas branch pipes; and annular fuel gas through holes are formed in the tail ends of the annular fuel gas spray pipes. By applying the technical scheme, the combustion efficiency can be improved, and the combustor can be heated uniformly.

An air-fuel ratio of an air-fuel mixture produced by fuel injected from a first injector into an intake port (or into a combustion chamber) is set in a range of 28 to 38. Therefore, when the temperature and pressure rise with a first combustion started by spark-ignition around a spark plug to the fuel injected from a second injector into the combustion chamber, the timing of starting a second compressive hypergolic ignition is optimized to provide a stable combustion state free of knocking and misfire.