Investigating the Effects of Variable Valve Timing on Spark Ignition Engine Performance

• Main Authors: Sepehr Bapiri, Cem Sorusbay
• Format: Article
• Language: English
• Published: Society of Polish Mechanical Engineers and Technicians 2019-06-01
• Series: Advances in Science and Technology Research Journal
• Subjects: engine performance; fuel consumption; variable valve timing; spark ignition engine; Turbocharger; AVL BOOST
• Online Access: http://www.journalssystem.com/astrj/INVESTIGATING-THE-EFFECTS-OF-VARIABLE-VALVE-TIMING-ON-SPARK-IGNITION-ENGINE-PERFORMANCE,103917,0,2.html

ABSTRACT: In this study, a prototype four-stroke spark ignition engine with four-cylinder (that each cylinder has two valves), with and without turbocharger which equipped with a system to adjustment of variable valve duration has been investigated. This study covers the effects of intake valve opening (IVO), Intake valve closing (IVC), exhaust valve opening (EVO) and exhaust valve closing (EVC) angles on engine performances and fuel economy. The calculations of engine performance were carried out using the1-Dimensional simulation with AVL BOOST software. The effects of different valve timing strategies and a combination of them from simulations were analyzed and compared with the reference fixed valve timing cases. It has been shown that substantial improvements in fuel consumption and performance can be achieved. The improvements of Indicate Specific Fuel Consumption (ISFC) are remarkable in turbocharged models. Furthermore, we can see the noticeable improvements in torque and power in the naturally aspirated engine.