Exhaust gas particulate measuring system

摘要

A gas sampling system 36 capable of testing and certifying internal combustion engines 16 under transient conditions is provided and includes a partial flow dilution tunnel 38 , master and slave mass flow controllers 80,60 and a transient dilution air flow controlling arrangement 110 . The transient dilution air flow controlling arrangement 110 measures the transient changes in intake air and varies the flow of diluent air to the partial flow dilution tunnel 38 . By controlling the diluent air in this manner ensures that a particle sample can be taken at any time that is at a constant proportion to the exhaust flow rate.