Numerical analysis of the injection law influence on NOx emissions for a compression ignited engine

Technical University of Cluj-Napoca, Cluj-Napoca, Romania

^* Corresponding author : dan.moldovnau@auto.utcluj.ro

Abstract

Under the present conditions, where sustained efforts are being made by researchers and automotive industry developers to reduce toxic gases (and fitting them into existing pollution standards), research is required to define the possible directions to be followed for this purpose. One of these directions is also presented in this paper.The paper presents research done by using numerical analysis of the influence of the injection law on NOx emission on compression ignited engines. Instead of a normal injection law, a particular injection law was considered to reduce the effect of the cavity on the fuel flow inside the injector in order to achieve a more homogeneous fuel jet exit at the injector.It is noted that there are NOx emission reductions of up to 20% (obtained at 760 degrees CA) compared to the initial injection law, which confirms the need to continue studying the presented research topic. There are also differences in the formation and development of NOx emission zones within the combustion chamber (the volume and positioning of the contact surface towards the walls of the combustion chamber)..