Flow estimation for secondary air system
AssigneeGarrett Transportation I Inc.
InventorsPaul Dickinson, Ondrej Santin, Malay C. Maniar
Life of this patent
Estimating the term…
Abstract
Methods and systems using model based and iterative calculations of mass flow throughout an internal combustion engine system. A secondary air injection valve is provided to selectively allow intake air to pass to the exhaust side of the engine system to aid in exothermic reaction with exhaust gasses exiting the engine for various purposes. The iterative calculations of mass flow include estimation of the mass flow through the secondary air injection valve.
Claims20
A method of operation in an engine system, the engine system including a combustion engine with an intake manifold and an exhaust manifold, a compressor configured to compress intake air upstream of the intake manifold, and an environmental catalyst device (ECD) downstream of the exhaust manifold configured to reduce one or more pollutants in exhaust air exiting the combustion engine, and a secondary air passage having a secondary air injection (SAI) valve, the secondary air passage and SAI valve controllably allowing compressed air from a first location downstream of the compressor and upstream of the intake manifold to be passed to a second location downstream of the exhaust manifold and upstream of the ECD, the method comprising:
- calculating a first pressure and a first temperature at the first location using one or more flow models and at least a sensed intake manifold pressure and a sensed intake manifold temperature;
- calculating an exhaust manifold pressure;
- and
- calculating a mass flow through the SAI valve from a model of the SAI valve using the first pressure, the first temperature, the exhaust manifold pressure, and the SAI control signal as inputs to the model of the SAI valve.
A vehicle comprising:
- combustion engine with an intake manifold and an exhaust manifold;
- a compressor configured to compress intake air upstream of the intake manifold;
- an environmental catalyst device (ECD) downstream of the exhaust manifold configured to reduce one or more pollutants in exhaust air exiting the combustion engine;
- a secondary air passage having a secondary air injection (SAI) valve, the secondary air passage and SAI valve controllably allowing compressed air from a first location downstream of the compressor and upstream of the intake manifold to be passed to a second location downstream of the exhaust manifold and upstream of the ECD;
- and
- a controller configured to perform a method comprising:
- calculating a first pressure and a first temperature at the first location using one or more flow models and at least a sensed intake manifold pressure and a sensed intake manifold temperature;
- calculating an exhaust manifold pressure;
- and
- calculating a mass flow through the SAI valve from a model of the SAI valve using the first pressure, the first temperature, the exhaust manifold pressure, and the SAI control signal as inputs to the model of the SAI valve.
Dependencies are inferred from the claim text.