摘要:
An improved engine fuel control detects combustion instability due to the use of high DI fuel during cold start and warm-up and compensates the fuel control for detected combustion instability through temporary enrichment of the delivered air/fuel ratio. When the engine idle speed error magnitude is less than a calibrated threshold, usage of high DI fuel is detected by identifying a surge signal based on the engine speed error fluctuation in a predetermined frequency range attributable to combustion instability due to the presence of high DI fuel in a cold engine. When the average amplitude of the surge signal exceeds a calibrated surge threshold, the presence of high DI fuel is detected. Additionally, the method is disabled for a prescribed period following commanded load transitions associated with the air conditioning system and the automatic transmission.
摘要:
An improved engine fuel control detects combustion instability due to the use of high driveability index (DI) fuel during cold start and warm-up and compensates the fuel control for detected combustion instability through temporary enrichment of the delivered air/fuel ratio. The usage of high DI fuel is detected during engine cranking by measuring the time required for the engine speed to increase from a lower reference speed to an upper reference speed, provided the engine run time is less than a calibrated value. A timer is started when the lower reference speed is achieved, and the timer value is compared to a crank time threshold determined as a function of the initial engine coolant temperature. If the timer value exceeds the crank time threshold before the engine speed reaches the upper reference speed, the presence of high DI fuel is indicated, and the air/fuel ratio is temporarily enriched.
摘要:
An improved engine fuel control detects combustion instability due to the use of high DI fuel during cold start and warm-up and compensates the fuel control for detected combustion instability through temporary enrichment of the delivered air/fuel ratio. The usage of high DI fuel is detected during an engine idle period following starting by monitoring the engine speed to identify an engine speed excursion more than a calibrated percentage below the desired idle speed. The detection method is enabled under specified environmental conditions, provided the engine run time is greater than a specified time and the engine temperature is within a specified range. Additionally, the method is disabled for a prescribed period following commanded load transitions associated with the air conditioning system and the automatic transmission. When the presence of high DI fuel is detected, and the air/fuel ratio is temporarily enriched to alleviate the instability and to ensure acceptable driveability without unnecessarily increasing hydrocarbon emissions in the engine exhaust gases.
摘要:
A method and apparatus for conducting dynamometric testing of an internal combustion engine at a test site under a simulated atmospheric pressure that differs substantially from an actual ambient atmospheric pressure existing at the test site. The internal combustion engine has an air inlet for supplying an intake airflow for combustion within the internal combustion engine and an exhaust outlet for exhausting an exhaust flow exiting from the internal combustion engine. The method includes the steps of subjecting the air inlet to the simulated atmospheric pressure, subjecting the exhaust outlet to the simulated atmospheric pressure and operating the internal combustion engine while both of the air inlet and the exhaust outlet are subjected to the simulated atmospheric pressure. The apparatus includes an exhaust pressure controller for maintaining the exhaust outlet of the internal combustion engine substantially equal to a determined exhaust pressure during operation of the internal combustion engine and an intake pressure controller for maintaining the air inlet of the internal combustion engine substantially equal to a determined intake pressure during operation of the internal combustion engine.
摘要:
An improved control methodology for an engine control valve, in which the valve is positioned in response to a commanded flow rate of the controlled medium. The method involves a valve characterization procedure in which the actual flow rate is measured for various combinations of valve position and pressure ratio across the valve, subject to a standard set of upstream pressure and temperature values. This results in a table of valve position in terms of pressure ratio and standard flow rate—that is, flow rate under the standard upstream pressure and temperature values. In operation, a controller addresses the table to obtain the desired valve position as a function of a determined pressure ratio across the valve, and a desired standard flow rate determined based on the commanded flow rate and the pressure and temperature of the controlled medium upstream of the valve, relative to the standard pressure and temperature values. The required calibration effort is significantly reduced compared to the usual ad-hoc approach, and the control is based on the physical characteristics of the valve so that the commanded flow rate can be scheduled based on engine control considerations. Additionally, the control is modular in nature, which minimizes the re-design and re-calibration efforts required due to changes in system design.
摘要:
An improved engine control utilizes a model-based technique to obtain an accurate estimate of barometric pressure with significantly reduced calibration time and effort. A mathematical model of mass air flow through the engine intake system is used to estimate the pressure ratio across the intake system as a function of mass air flow, the effective intake area, and the intake air pressure and temperature. The barometric pressure is then determined from the estimated ratio, and used in the calculation of various gas flows for control purposes. The mass air flow information may be provided by a mass air flow sensor, or alternatively, may be determined based on engine flow rate estimations. Because the estimation is model-based, no special calibration is needed to ensure accuracy at high altitudes.
摘要:
To obtain a quality-meat-attached backbone part suitable as a material for minced fish the invention proposes cutting off a fin part and a kidney from a meat-attached backbone part obtained when filleting a fish into three pieces. The meat-attached backbone part is conveyed by a pair of upper and lower conveyor belts while being sandwiched and held between the belts. When the backbone part reaches a fin cutter arranged in a midstream of the conveyance, a belly part is pushed by a first pushing lever while a back part of the meat-attached backbone part is received and stopped by a receiving and stopping lever, and the back skin from a back fin to a tail fin is cut off by the fin cutter. Then, when the meat-attached backbone part reaches a kidney cutter, the belly part of the meat-attached backbone part is pushed by a second pushing lever to position the kidney-attached backbone section of the meat-attached backbone part at a cutting position by a kidney cutter. The kidney-attached backbone section is cut off by the kidney cutter to obtain the quality-meat-attached backbone part.
摘要:
An improved closed-loop feedback fuel control with a model-based A/F ratio estimator, wherein the estimator, controller and portions of the model are updated on a fixed time interval basis, thereby minimizing the impact of the control on event-based throughput. Engine transport delays and oxygen sensor dynamics are modeled to estimate the sensed A/F ratio, and the estimate is compared with the sensed A/F ratio to adaptively adjust the model and to develop a closed-loop adjustment of the commanded fuel amount. The engine transport delay model is carried out on an engine event basis, but the sensor dynamics model is carried out on a time basis to accurately reflect the analog nature of the sensor. The estimator and the controller are also carried out on a time basis to reduce throughput requirements at higher engine speeds, and the control gain is scheduled to account for differences between the engine event and time update rates. The control enables numerous control enhancements, including flexibility to topology variations (such as sensor placement, sensor type and sensor characteristics), ease of calibration, and the ability to easily calibrate and schedule A/F ratio perturbations for catalytic conversion efficiency optimization.
摘要:
Transient internal combustion engine fueling control with reduced calibration burden and increased precision through application of a convection model to estimate the mass transfer of fuel between cylinder intake gasses and intake system components primarily as a function of fuel film temperature and gas flow across fuel film on such components. The convection model applies potential/flow conditions in proximity to fuel film on intake components of an engine cylinder to predict the depletion of the fuel film and generates an impact factor representing the fraction of injected fuel impacting intake system components in a manner providing fuel control stability. The convection model applies an intake valve temperature estimate generated simply as a function of air mass flow rate through the intake system to be used in the calculation of the film convection parameters.
摘要:
An internal combustion engine system includes a plurality of pneumatic elements including pneumatic resistances, pneumatic capacitances, and pneumatic sources. A pneumatic state model determines a pressure rate of change and pressure for certain areas of the internal combustion engine system designated as pneumatic nodes from selected flows of gas mass associated with pneumatic elements coupled to the certain areas.