| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 243398 | Applied Energy | 2012 | 12 Pages |
An experimental investigation was performed with a view to comparing high and low pressure exhaust gas recirculation systems (HP and LP EGR) fitted on an automotive turbocharged diesel engine, focusing on analysing their influence on fuel consumption, pollutant emissions and the combustion process. Following the development of a prototype cooled LP EGR circuit, the main engine and turbocharger parameters were measured in six part-load operating conditions related to the European driving cycles. Different operating modes were considered, from the simplest and most commonly investigated (without EGR, with HP or LP EGR) to more complex schemes, namely the simultaneous application of high and low pressure recirculation and the addition of variable nozzle turbine (VNT) control. The extensive experimental database made it possible to confirm literature concerning the comparison of recirculating systems and the potential of LP EGR on engine intake temperature and NOx reductions. New aspects were also analysed, such as the balance of the high and low pressure EGR rate in order to achieve maximum NOx reductions in simultaneous applications, the interactions between EGR circuit management and the application of VNT control in order to improve the trade-off between fuel consumption and NOx and soot emissions.
► Low pressure exhaust gas recirculation circuit design and setup. ► Experimental comparison of HP and LP EGR in six part load operating conditions. ► Simultaneous application of HP and LP EGR and VNT opening degree control. ► Influence on engine operating parameters, fuel consumption, NOx and soot emissions. ► Comparison of different EGR systems control strategies for maximum NOx reduction.
