Apparatus and method for determining the octane number of test fuels.

摘要

First and second reference fuels having different known octane numbers and a test fuel having an unknown octane number are each provided individual through a pump to the fuel inlet of an engine at the substantially constant mass flow rate which results in substantially maximum knocking conditions for each of the fuels. The octane number of the test fuel is determined based on measurements of the rate of change of the cylinder pressure in the engine when the first and second reference fuels and the test fuel are flowing to the engine.