The Effect of Valve Lift Shape and Timing on Air Motion and Mixture Formation of DISI Engines Adopting Different VVA Actuators

S. Diana; B. Iorio; V. Giglio; G. Police

doi:10.4271/2001-01-3553

2001-09-24

The Effect of Valve Lift Shape and Timing on Air Motion and Mixture Formation of DISI Engines Adopting Different VVA Actuators 2001-01-3553

A number of Variable Valve Actuators (VVA) has been recently proposed to improve the performances and the part load efficiency of spark ignition engines. Due to their peculiarity, these systems work with different strategies (late or early inlet valve closing, reduced lift etc.).

The shape and the timing of the valve lift affect not only the pumping losses, but also air motion inside the cylinder. That influences mixture formation and combustion evolution of Direct Injection Spark Ignition (DISI) engines.

The present paper compares the performances of different VVA systems with the aid of a 1D code for the simulation of the inlet and of the exhaust phases, and of a fluid-dynamic 3D code to evaluate mixing phenomena inside the cylinder.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Digital $37.00 Print $37.00

Preview Document

We also recommend:

Standards

SAE Mobilus®

Publications

News

Events

Professional Development

A World in Motion (PreK-12)

Participate with SAE

SAE Membership

Donate

The Effect of Valve Lift Shape and Timing on Air Motion and Mixture Formation of DISI Engines Adopting Different VVA Actuators 2001-01-3553

SAE MOBILUS