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oai:mountainscholar.org:10217/675602025-12-30T03:22:26Zcom_10217_100532com_10217_100000com_10217_100470com_10217_100303col_10217_100538col_10217_100472

Gattoni, John, author Olsen, Daniel, advisor Marchese, Anthony, committee member Young, Peter, committee member 2007-01-03T08:09:57Z 2013-06-01T08:10:42Z 2012 Gattoni_colostate_0053N_11066.pdf ETDF2012500125MCEN http://hdl.handle.net/10217/67560 https://doi.org/10.25675/3.018518 High exhaust emissions reduction efficiency from an Internal Combustion Engine (ICE) utilizing a Non Selective Catalyst Reduction (NSCR) catalyst system requires complex fuel control strategies. The allowable equivalence ratio operating range is very narrow where NSCR systems achieve simultaneous reduction of Carbon Monoxide (CO), Nitrogen Oxides (NOx), Total Hydrocarbons (THC), Volatile Organic Compounds (VOC's), and formaldehyde (CH2O). This range is difficult to maintain as transients are introduced into the system. Current fuel control technologies utilizing lambda sensor feedback are reported to be unable to sustain these demands for extended operation periods. Lambda sensor accuracy is the critical issue with current fuel controllers. The goal of this project was to develop a minimization control algorithm utilizing a Continental NOx sensor installed downstream of the NSCR catalyst system for feedback air/fuel ratio control. When the engine is operated under lean conditions, NOx is produced in the engine out exhaust emissions and the NOx sensor responds accordingly. When the engine is operated under rich burn conditions, the NSCR catalyst system produces Ammonia (NH3). NOx sensors have a cross sensitivity to NH3 and will respond as though it has been exposed to NOx. This behavior provides a unique control strategy that allows lambda sensor calibration to be ignored. Testing was performed on a Cummins-Onan Generator Set, model GGHD 60HZ, capable of a power output of 100kW at standard ambient air conditions. The engine was reconfigured to operate utilizing an electronic gas carburetor (EGC2) with lambda sensor feedback, manufactured by Continental Controls Corporation (CCC) and a high reduction efficiency NSCR catalyst system manufactured by DCL International. A Data Acquisition (DAQ) system manufactured by National Instruments (NI) acquired the NOx sensor output. The control algorithm was programmed utilizing a LabVIEW interface and a feed forward command was executed through the NI DAQ system to the CCC EGC2 where the fuel trim adjustment was physically made. Exhaust gas species measurements were acquired via a Rosemount 5-gas analyzer and a Nicolet 6700 FTIR. Fuel composition was acquired utilizing a Varian CP-4900 Micro GC and Air Fuel Ratio (AFR) was obtained with an ECM AFRecorder 4800R. Results utilizing NOx sensor feedback control revealed that under steady state operating conditions, improvements in emissions reduction efficiency of CO, NOx, and THC were significant. The system was also evaluated during load and fuel composition transients. born digital masters theses English eng Colorado State University. Libraries 2000-2019 Copyright and other restrictions may apply. User is responsible for compliance with all applicable laws. For information about copyright law, please see https://libguides.colostate.edu/copyright. NSCR fuel control NOx sensor natural gas engines catalyst control algorithm Advanced control techniques and sensors for gas engines with NSCR Text 2013-06-01 2013-06-01 This Item is protected by copyright and/or related rights (https://rightsstatements.org/vocab/InC/1.0/). You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s). Master of Science (M.S.) Masters Mechanical Engineering Colorado State University open.access