Thermodynamic analysis of an engine with compression ignition according to the controlled Miller cycle

Abstract

Introduction (problem statement and relevance). This article presents the thermal calculation results of an in-line six-cylinder highly accelerated engine with a displacement of 13 liters with compression ignition, according to the controlled Miller cycle. The result of the study is the main performance indicators that testify the potential for using the controlled Miller cycle with the intake valves early closing in a highly forced engine as one of the ways to improve energy efficiency.The purpose of the study was to evaluate the effect of valve timing and the intake and exhaust valves lift on the average specific fuel consumption of a highly forced automobile engine with compression ignition at the early stages of design.Methodology and research methods. Computational and theoretical studies were carried out using mathematical modeling of thermodynamic processes in a one-dimensional setting. The reliability of the calculations was verified by comparing the simulation data and the results of experimental studies of the internal combustion engine. To develop the laws of valve lift, the method of sequential nonlinear quadratic programming was used.Scientific novelty and results. The law of valve lift of a highly accelerated automobile engine with compression ignition according to the controlled Miller cycle has been developed, which made it possible to reduce the minimum specific fuel consumption by up to 7.8% in comparison with the basic version of the engine.Practical significance. The developed thermodynamic models make it possible to evaluate the qualitative and quantitative contribution to achieving fuel efficiency through the use of the controlled Miller cycle and obtain initial data in the form of a valve lift law for further work on the development of a valve timing mechanism.