Prediction of nitrogen oxide emissions from diesel exhaust gases when using composite fuel

Abstract

BACKGROUND: The problem of using composite fuel (CF) in diesel engines consists in a wide variation of their physicochemical properties, which affect the emission of nitrogen oxides (NOx) with ex-haust gases (EG). Therefore, the predictive assessment of the formation of NOx with EG when using CF is very relevant. AIMS: Predictive assessment of quantitative NOx emission with diesel EG when using various types and compositions of CF. Scientific novelty lies in development of the method of prediction of NOx emission by a diesel engine when using CF. METHODS: The method of prediction of quantitative NOx emissions with diesel EG regarding the use of various CF kinds and compositions has been developed. Predictive indicators of NOx emissions have been defined. Multi-parameter characteristics of NOx emission with EG of the D-245.582 diesel engine of 4ChN 11.0/12.5 size have been obtained experimentally. Degree of convergence of the experimental data with the calculated values is assessed. RESULTS: As a result of the carried-out studies, it was theoretically established that the load (pe) increase from 0.2 to 1.0 MPa, the engine speed (n) decrease from 1800 to 1400 min-1 and decrease of mass fraction of rapeseed oil (RO) and ethanol (E) in CF from 40 to 20% lead to increased NOx emissions with diesel EG from 131 to 2225 ppm and from 75 to 1450 ppm respectively. The increase in NOx emissions with the EG from 152 to 2125 ppm for CF consisting of DF and RO and from 175 to 1550 ppm for CF consisting of DF and E in the above mentioned operating modes experimentally confirmed. The degree of convergence of the experimental data with the calculated values is 90.14%, which in turn indicates the possibility of using the developed methodology as a predictive indicator. CONCLUSIONS: As a result of the studies, it was established that the developed method of prediction of quantitative NOx emissions with diesel EG is highly likely to use for preliminary assessment when various CF kinds and compositions are considered, as the degree of convergence of the experimental data with the calculated values, assessed with a statistical processing method and experimental error calculation, is 90.14%.