摘要 |
An estimation apparatus for determining a residual burned gas mass fraction of an internal combustion engine includes a single-cylinder simulator and an optimizer. The residual estimation apparatus does not rely on accurate knowledge of, or calculation of the details of the complex pulsating pressures and flows at the intake and exhaust valves. Instead an iterative approach uses primarily measured cylinder pressure and airflow as driving inputs, to ensure that the simulation states (i.e., pressure, temperature, and composition) of the cylinder gas contents, at the time of intake valve closing, are correct. The burned gas fraction calculated by the engine simulator is then taken as an estimate of that in the actual engine.
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