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 scale diesel engines from scale model experiments, and shows the results of experiments conducted to validate the scale model theory. 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. Based on an analysis of NO formation, an algorithm to predict emissions is also established. An experiment was performed to compare predictions based on scale model experiments and experimental results 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.