Idling Performance under Valve Deactivation Strategy in Port Fuel Injection Engine

A. S. Paimon; S. Rajoo; W. Jazair; M. A. Abas; Z. H. Che Daud

doi:10.15282/ijame.16.4.2019.01.0535

Authors

A. S. Paimon Malaysia-Japanese International Institute of Technology, Universiti Teknologi Malaysia, 54100, Kuala Lumpur, Malaysia, Phone: +60133566240
S. Rajoo Centre for Low Carbon Transport In Cooperation with Imperial College London, Universiti Teknologi Malaysia, 81310 Skudai, Johor, Malaysia
W. Jazair Malaysia-Japanese International Institute of Technology, Universiti Teknologi Malaysia, 54100, Kuala Lumpur, Malaysia Email: solehinpaimon@gmail.com Phone: +60133566240
M. A. Abas Centre for Low Carbon Transport In Cooperation with Imperial College London, Universiti Teknologi Malaysia, 81310 Skudai, Johor, Malaysia
Z. H. Che Daud School of Mechanical Engineering, Universiti Teknologi Malaysia, 81310 Skudai, Johor, Malaysia

DOI:

https://doi.org/10.15282/ijame.16.4.2019.01.0535

Keywords:

Idling, Reduced idle speed, VVA, Valve deactivation, Combustion stability

Abstract

This paper investigates the effect of valve deactivation (VDA) on idling performance in port fuel injection (PFI) engine. The test was conducted on 1.6L, 4-cylinder engine with PFI configuration. One of the two intake valves in each cylinder was deactivated (zero lift on deactivated port) and fuel injector was modified to only provide fuel spray on the active intake port. In-cylinder pressure was recorded by the combustion analyzer in order to measure and analyze the combustion characteristics. From the test, there are up to 6% of fuel consumption improvements across all the test conditions. Better combustion stability is achieved at very low idling speed (throttle position, TP = 2%) as a lower coefficient of variation of engine speed (COVrpm) and coefficient of variation indicated mean effective pressure (COVimep) were recorded. Increased intake velocity and swirl flow in the VDA strategy creates more turbulence intensity causing higher heat release rate and faster combustion. However, there is no significant difference in the pumping work during the intake cycle but there is extra pumping work recorded towards the end of expansion stroke due to the very early end of combustion. Therefore, valve deactivation strategy provides limited positive improvement to the idling performance in PFI engine.