EFFECT BY GUIDE VANE SWIRL AND TUMBLE DEVICE TO IMPROVE THE AIR-FUEL MIXING OF DIESEL ENGINE RUNNING WITH HIGHER VISCOUS FUELS

摘要

The purpose of this study was to investigate the effect guide vane swirl and tumble device (GVSTD) on the in-cylinder airflow particularly to generate turbulent kinetic energy (TKE) and velocity inside the combustion chamber and around fuel injected region. High velocity and TKE would accelerate the evaporation, diffusion and mixing processes of CI engines, particularly when alternative fuels of higher viscosity and density (known as HVF-higher viscous fuel) are used. A verified simulation base model was prepared by the SolidWorks software and analysed using ANSYS software to study the reference data of the resulting in-cylinder airflow characteristics. Then GVSTD models were developed and imposed on the intake runner of the base model. The parametric optimization technique was used to find the optimum number of vanes for the GVSTD model. This was done by preparing 10 GVSTD models with the vane number varied from 3 to 12. The models were then tested on the base model individually. Generally, GVSTD improve in-cylinder TKE and velocity. Additionally, this research found that GVSTD with 3 vanes resulted in an improved TKE and velocity of about 6.3% and 10.4% respectively when compared to the base model. Therefore, it may be said that the use of GVSTD can increase the chances to improve the performance of a CI engine and reduce the emission when run on HVF.