tailieunhanh - Numerical simulation of airflow around vehicle models

This article carries out the numerical simulation of airflow over three dimensional car models using ANSYS Fluent software. The calculations have been performed by using realizable k- turbulence model. | Vietnam Journal of Science and Technology 56 (3) (2018) 370-379 DOI: NUMERICAL SIMULATION OF AIRFLOW AROUND VEHICLE MODELS Nguyen Van Thang1, *, Ha Tien Vinh1, Bui Dinh Tri1, 2, Nguyen Duy Trong1 1 Institute of Mechanics, Vietnam Academy of Science and Technology 2 Vietnam Academy of Science and Technology * Email: thangnv2010@ Received: 6 July 2017, Accepted for publication: 17 May 2018 Abstract. This article carries out the numerical simulation of airflow over three dimensional car models using ANSYS Fluent software. The calculations have been performed by using realizable k- turbulence model. The external airflow field of the simplified BMW M6 model with or without a wing is simulated. Several aerodynamic characteristics such as pressure distribution, velocity contours, velocity vectors, streamlines, turbulence kinetic energy and turbulence dissipation energy are analyzed in this study. The aerodynamic forces acting on the car model is calculated and compared with other authors. A rear wing shows a slight increase in the drag coefficient and a remarkable decrease in the lift coefficient. A change of lift force thus improves the car stability. Key words: k- turbulence model, automotive aerodynamics, drag, lift Classification numbers: ; ; . 1. INTRODUCTION In recent decades, computational fluid dynamics (CFD) has been playing an important role in engineering and industrial problems. The CFD technology has applied in research, design and improvement of aerodynamic car geometry. Therefore, automotive industry has a rapid development every year. The Ahmed model was described and performed experimentally by Admed et al. [1]. Two test cases with slant angles of 25 and 35 degrees are estimated. The drag force caused by air flow over the car body at velocities of 40 and 60 m/s is examined. Aljure et al. [2] carried out the numerical simulations of flow around two car models, the Ahmed and the Asmo cars .