Simulating Transient Multi-Cylinder Engine Gas Exchange Dynamics on a Single-Cylinder Research Engine 2006-01-1074

This paper provides design, development details, and experimental data of an invention that is able to replicate the transient intake gas dynamics of a multi-cylinder engine on a single-cylinder research engine. This invention directly addresses and solves a significant problem that has persisted in the engine research and development community for over 50 years. Single-cylinder engines have many attractive attributes for use in research and development of multi-cylinder engines, due to their low cost, flexibility, and easy access for instrumentation. However, engine manufacturers continue to decrease the use of these engines in the engine development process because their dynamic and transient behaviors differ significantly from that of the multi-cylinder engine. The most significant differences are in rotational dynamics, gas exchange dynamics, and inter-cylinder dynamic coupling. The device described in this paper addresses the second and third of these issues, and there will also be a brief description of another device that addresses the first issue. Operating together, these devices are able to accurately replicate much of the transient and steady state behavior of the multi-cylinder engine dynamics on a single-cylinder engine.

The paper will describe the goals of the intake airflow simulator development, including other applications in simulating turbocharged or supercharged engines. It will also present details of the invention and its development, as well as aspects of how the device is controlled. Experimental data will be included that will demonstrate the performance of the intake airflow simulator in both steady state and transient operation on an operating engine. Finally, a discussion about the important implications this device has on decreasing the time and cost of engine development, and improving test results and their application to multi-cylinder engines will be presented.