Dimensional Optimization of Key Parameters Using DoE Technique to Achieve Better NOX Emission Values in Mass Production of Single Cylinder Small Diesel Engines for 3 Wheeler Applications. 2020-01-1356
Oxides of Nitrogen (NOx) emissions are considered as one of the
harmful emissions globally which has a direct influence on human
beings as well as the environment. This works deals about a
strategy for reducing NOx pollutant from an automotive engine.
Catalytic converters and particulate filters are mostly used as
after treatment device for CI engines to control the limits of the
pollutants from the tail pipes, but the real ingenuity lies in
achieving the same effect through in - cylinder combustion.
Optimization of the critical factors like Nozzle Tip Protrusion
(NTP), Static Injection Timing (SIT), Bumping Clearance (BC) and
Swirl Number are the most important engine design parameters in
achieving the optimum combustion which might result in the release
of minimal harmful pollutants. In this work, L9 Orthogonal Array
(OA) table was used in designing experiments for studying the
interactive model between the said factor and its levels on NOx
emissions. Absolute value of NTP considering the tolerance limit is
set as 3.0 mm, 3.15 mm and 3.30 mm and similarly SIT, BC and Swirl
Rate is set as 0.19 mm, 0.23 mm, & 0.27mm, 0.65mm, 0.70 mm
& 0.75 mm and 2700 rpm, 2750 rpm and 2800 rpm respectively.
Single cylinder diesel engine was chosen as the test engine. Test
was conducted on the basis of standard OA table and corresponding
NOx emissions were measured. It is found that, NTP of 3.0 mm, SIT
of 0.27 mm, BC of 0.65 mm and Swirl Rate of 2800 rpm yielded the
optimum NOx emissions consistently. It comes to know that the above
mentioned process combination statistically demonstrated lesser
NOx. It is concluded from the results that the reduction of NOx by
22% with minimum engine to engine variation is achieved without
increase in the manufacturing cost by this technique.