Port Design Criteria for 2-Stroke Loop Scavenged Engines Universita di Modena e Reggio Emilia

Format:

Conference/Event

Author/Creator:

Mattarelli, Mattarelli, author.

Contributor:

Rinaldini, Carlo Alberto

Savioli, Tommaso

Conference Name:

SAE 2016 World Congress and Exhibition (2016-04-12 : Detroit, Michigan, United States)

Language:

English

Physical Description:

1 online resource

Place of Publication:

Warrendale, PA SAE International 2016

Summary:

AbstractInterest in 2-stroke engines has been recently renewed by several prototypes, developed for the automotive and/or the aircraft field. Loop scavenging, with piston controlled ports is particularly attractive, but the configurations successfully developed in the past for motorbike racing (in particular, the 125cc unit displacement, crankcase pump engines), are not suitable for automotive applications. Therefore, new criteria are necessary to address the scavenging system design of the new generation of 2-stroke automobile/aircraft engines.The paper reviews the transfer ports optimization of a loop scavenged 2-stroke cylinder, whose main parameters were defined in a previous study. The optimization has been carried by means of a parametric grid, considering 3 parameters (2 tilt angles, and the focus distance), and 3 different engine speeds (2000-3000-4000 rpm, assuming a Diesel engine). A set of scavenging CFD-3d simulations have been performed by using a customized version of KIVA-3V. The numerical approach was experimentally calibrated in a previous project (see appendix 1)The simulations results are presented by means of maps showing the influence of the geometrical parameters on the main scavenging coefficients.Finally, a refined mesh has been constructed for the optimum configuration found in the previous parametric analysis, and a set of multi-cycle simulations have been performed. The results demonstrated the very good efficiency of the scavenging process, close to a perfect displacement for delivery ratio up to 1.5, or for residuals fraction higher than 50%

Notes:

Vendor supplied data

Publisher Number:

2016-01-0610

Access Restriction:

Restricted for use by site license