CFD Simulation of Knock Onset in a Heavy-Duty Spark Ignition Gas Engine

Abstract

 Abstract: The paper describes a method for evaluating knocking onset with computational fluid dynamics (CFD) numerical model of the combustion process of spark ignited (SI) gas engine and methods for assessing the probability of knocking combustion based on this model. The probability of knocking combustion, which characterizes the boundary condition between normal combustion and knocking, is determined (8%). An optimization study of the influence of adjustment parameters on the probability of knocking based on a three-dimensional numerical model is carried out. The developed and tested technique allows one to monitor the tendency of the influence of various adjustment parameters on the probability of knocking in a SI gas engine. Keywords: natural gas, spark ignition gas engine, knock onset, computational fluid dynamic, combustion process, start of combustion test bench, knocking probability, knock index.