An Integrated System to reduce Emissions from Industrial Naturally Aspirated Reciprocating Engine — Performance assessment of an Amperometric NOx/O2 Sensor.
2022-01-0697
03/29/2022
- Event
- Content
- Emission reduction from Industrial naturally aspirated reciprocating engines (INARE) is of high priority to regulatory agencies due to their significant contribution to overall pollutant emissions. INAREs are well-known for their simplicity and are originally designed to work at some specific Air-to-Fuel ratios (AFRs). The AFR has been used as an effective parameter to control emissions in modern engines. However, such AFR control systems are not present in many INAREs. To solve this challenge, a novel, cost-effective retrofit kit is proposed in this paper that can be integrated with typical INAREs to control AFR and improve their performance and emissions at wide-ranging operating conditions. The retrofit kit comprises an air bypass mechanism integrated with a control unit and amperometric sensors adapted from the automobile industry. The amperometric sensors operate in the limiting current region, which enables the measurement of a wide range of NOx/O2 concentrations. This paper thoroughly describes these sensors and presents models that are developed to map their performance. The model incorporates electrode polarization which includes activation, ohmic and concentration losses as well as diffusion mechanism through the diffusion barriers. The characteristic current-voltage (I-V) curves for different mole fractions of NOx/O2 are generated successfully using Engineering Equation Solver (EES) software. The results show that the behavior of the sensor changes with different values of parameters such as exhaust gas temperature, cell resistance, kinetic parameters and diffusion coefficient. Such a model is an essential tool to estimate the electrochemical performance of NOx/O2 sensors. It will be employed in the subsequent phases of this study to develop an appropriate control algorithm for the effective management of the retrofit kit mentioned above. The sensor is intended for calibration at very high excess O2 in the following phases of our study, as described in this paper.
- Citation
- Hassan, H., Hartless, M., Jha, P., and Kazempoor, P., "An Integrated System to reduce Emissions from Industrial Naturally Aspirated Reciprocating Engine — Performance assessment of an Amperometric NOx/O2 Sensor.," SAE Technical Paper 2022-01-0697, 2022, .