Abstract: A method and system for improving starting of an engine that may be repeatedly stopped and started is presented. In one example, the method adjusts a port fuel injection amount in response to engine stopping position. The engine stopping position may be indicative of a fraction of injected fuel that enters a cylinder for a first combustion event since engine stop.

Abstract: Various embodiments related to controlling EGR in an engine are disclosed. In one embodiment, a first EGR amount is supplied to a cylinder at a first temperature and a first engine speed and load. Further, at the first engine speed and load, as engine temperature increases from the first temperature to a second temperature, a first fuel amount is injected after exhaust valve closing and before intake valve opening while a second EGR amount is supplied to the cylinder that is greater than the first EGR amount.

Abstract: A vehicle system operation method is provided. The method comprises, during a first operating condition, increasing back pressure in a first exhaust conduit positioned upstream of a turbine and downstream of a first emission control device and during a second operating condition, reducing back pressure in the first exhaust conduit and flowing boosted air from downstream of a compressor into a second exhaust conduit positioned upstream of a second emission control device and downstream of the turbine.

Abstract: Embodiments for heating an emission control device are provided. In one example, a method for a turbocharged engine comprises during an engine cold-start, delivering boosted air from downstream of a compressor into a wastegate duct coupled across a turbine and exothermically reacting a reductant with the boosted air upstream of an exhaust emission control device. In this way, boosted air may be used to initiate an exothermic reaction to heat the device.

Abstract: An agile optical imaging system for optical coherence tomography imaging using a tunable source comprising a wavelength tunable VCL laser is disclosed. The tunable source has long coherence length and is capable of high sweep repetition rate, as well as changing the sweep trajectory, sweep speed, sweep repetition rate, sweep linearity, and emission wavelength range on the fly to support multiple modes of OCT imaging. The imaging system also offers new enhanced dynamic range imaging capability for accommodating bright reflections. Multiscale imaging capability allows measurement over orders of magnitude dimensional scales. The imaging system and methods for generating the waveforms to drive the tunable laser in flexible and agile modes of operation are also described.

Abstract: A system in an internal combustion engine is provided. The system a combustion chamber, a first exhaust port in fluidic communication with the combustion chamber, a second exhaust port in fluidic communication with the combustion chamber, and a direct fuel injector positioned between the first and second exhaust port and fluidly communicating directly with the combustion chamber.

Abstract: A spark ignition direct injection fuel cylinder for an engine includes a rotatable valve at a curved wall of an intake duct. The rotatable valve provides a variable step in to adjust the degree of tumble airflow while reducing flow restriction to improve engine performance across operating conditions.

Abstract: A method of forming a bowl in a top surface of a piston for an internal combustion engine includes machining the top surface of the piston to form a spherical depression in the top surface wherein the top surface comprises a dome prior to the machining and a center of the bowl is displaced from a center of the piston by at least one-quarter of a diameter of the piston. In one embodiment, the method includes machining recesses in the top surface aligned, respectively, with intake valves, an exhaust valve, and spark plug when installed. Because the bowl is smooth and shallow, the surface area of the combustion chamber is less than with a deeper bowl of complicated shape. Lowering surface area in the combustion chamber leads to improved fuel economy.

Abstract: A method for engine starting is provided. The method may include performing idle-stop operation, and during a subsequent re-start, applying multi-strike ignition operation for a first combustion cycle. In this way, improved engine starting may be achieved with reduced emissions.

Abstract: A spark ignition direct injection fuel cylinder for an engine includes a rotatable valve at a curved wall of an intake duct. The rotatable valve provides a variable step in to adjust the degree of tumble airflow while reducing flow restriction to improve engine performance across operating conditions.

Abstract: A method for improving starting of an engine that may be operated with fuels having varying alcohol concentrations is presented. In one embodiment, the method adjusts a compression ratio of an engine in response to a number of combustion events after an engine stop and a concentration of alcohol in a fuel supplied to the engine. The method may make engine starting more repeatable at lower engine temperatures.

Abstract: A system and a method of facilitating fuel vaporization in a directly injected internal combustion engine are provided. As one example, the method comprises: closing an exhaust valve of the cylinder; opening an intake valve after the exhaust valve has closed; moving a piston of the cylinder away from top dead center between the closing of the exhaust valve and the opening of the intake valve to expand the cylinder volume and reduce a pressure within the cylinder to below a pressure of an air intake manifold of the cylinder; and initiating an injection of fuel directly into the cylinder via an in-cylinder injector after the exhaust valve has closed.

Abstract: A method of forming a bowl in a top surface of a piston for an internal combustion engine includes machining the top surface of the piston to form a spherical depression in the top surface wherein the top surface comprises a dome prior to the machining and a center of the bowl is displaced from a center of the piston by at least one-quarter of a diameter of the piston. In one embodiment, the method includes machining recesses in the top surface aligned, respectively, with intake valves, an exhaust valve, and spark plug when installed. Because the bowl is smooth and shallow, the surface area of the combustion chamber is less than with a deeper bowl of complicated shape. Lowering surface area in the combustion chamber leads to improved fuel economy.

Abstract: A method for engine starting is provided. The method may include performing idle-stop operation, and during a subsequent re-start, applying multi-strike ignition operation for a first combustion cycle. In this way, improved engine starting may be achieved with reduced emissions.

Abstract: A combustion system for a direct-injection, spark-ignition engine is disclosed. A side-mounted fuel injector located outboard the intake valves directs multiple fuel jets into a shallow, spherical bowl formed in a domed piston. Both good mixing to facilitate good air utilization with early injection and an ignitable mixture at the spark plug with late injection to facilitate cold start are provided with such a combustion system. Because the bowl is smooth and shallow, the surface area of the combustion chamber is less than with a deeper bowl of complicated shape. Lowering surface area in the combustion chamber leads to improved fuel economy.

Abstract: A method for improving starting of an engine that may be operated with fuels having varying alcohol concentrations is presented. In one embodiment, the method adjusts a compression ratio of an engine in response to a number of combustion events after an engine stop and a concentration of alcohol in a fuel supplied to the engine. The method may make engine starting more repeatable at lower engine temperatures.

Abstract: A method for engine starting is provided. The method may include performing idle-stop operation, and during a subsequent re-start, applying multi-strike ignition operation for a first combustion cycle. In this way, improved engine starting may be achieved with reduced emissions.

Abstract: A system and a method of facilitating fuel vaporization in a directly injected internal combustion engine are provided. As one example, the method comprises: closing an exhaust valve of the cylinder; opening an intake valve after the exhaust valve has closed; moving a piston of the cylinder away from top dead center between the closing of the exhaust valve and the opening of the intake valve to expand the cylinder volume and reduce a pressure within the cylinder to below a pressure of an air intake manifold of the cylinder; and initiating an injection of fuel directly into the cylinder via an in-cylinder injector after the exhaust valve has closed.

Abstract: A system and a method of facilitating fuel vaporization in a directly injected internal combustion engine are provided. As one example, vaporization may be improved by coordinating the timing of the directly injected fuel with intake valve opening while also utilizing negative valve overlap between the intake and exhaust valves to generate reduced pressures within the cylinder.

Abstract: To partially supplant the use of fossil fuels in diesel engines, oxygen-containing fuels, such as biodiesels, are proposed as blending agents in diesel fuel. Engine calibration coefficients to control EGR rate, timings and quantities of fuel injection pulses, turbocharger boost, etc, can be determined to compensate for the lower energy content of such oxygenate blends compared to diesel fuels. According to an embodiment of the disclosure, the fuel quantity of each of multiple injection pulses is increased proportionally to compensate for the impact of oxygenates. An adjustment in the fuel injection quantity is performed in response to a new tank of fuel and the adjustment is applied for that tank of fuel. A fuel compensation factor (FCF) can be determined based on the actual amount of fuel injected compared to the expected amount of diesel fuel at the present operating condition.