Study on Predicting Combustion and NOx Formation in Diesel Engines from Scale Model Experiments.

Abstract

The paper discusses the methodology of predicting combustion and NO formation in large diesel engines from scale model experiments, together with the experimental results compared with the theoretical predictions. Combustion similarity means that flow patterns and flame distribution develop similarly in differently sized engines, so allowing heat release rates and thermal efficiency to be predicted from scale model experiments. One of the objectives of this research is to validate the establishment of the combustion similarity by experiments. Additionally, an algorithm to predict NO emissions is also established in this paper, based on the combustion similarity and unique characteristics of NO formation. An experimental data was obtained with two sets of similar engines ranging from 85 to 125 and from 600 to 800 mm bore. The results showed good agreement with the theoretical predictions, indicating possibility of the scale model experiment for diesel engine combustion.