Measuring the Exhaust Emission from a Small Scale Combustion Engine

The purpose of this research to understand, repairs, refurbish, calibrate, and test a combustion gas emission console for use in determining the performance of a small-scale (50 cc) reciprocating internal combustion engine.  In addition to the gas sampling line, which chills the sample and removes the water, the gas emission console is composed of three parts.  The first part is the hydrocarbon analyzer, in which the ion current from a sample gas heated in a hydrogen/helium flame is directly proportional to the rate of the carbons entering the burner, thus making a measure of the concentration of unburned hydrocarbons.  The second part is a non-dispersive infrared (NDIR) analyzer in which infrared light absorbed in different wavelength bands are used to measure the concentration of CO and CO₂ by the use of a Luft detector.  Finally, a nitrogen oxide analyzer operates on the principle of chemiluminscence, where NO is oxidized with ozone, producing some excited state NO₂ which gives off light as it decays back to the ground state.  By running two tests, one after first converting all the NO₂ to NO, it is possible to measure both NO and NO₂ using this method and taking the difference between the two tests.  The first step in the research is to understand the methods used by each module.  Then, the flow panel controlling the system will be repaired and calibrated, followed by refurbishment and testing of the hydrogen burner in the hydrocarbon analyzer and the ozone reactor in the NOx analyzer.