Research on the Aerodynamic Characteristics of the Ahmed Body with a Modified LRN $${k-\varepsilon}$$ k - ε Turbulence Model Using a Transition-Code-Based Method

• DOI: 10.1007/s13369-015-1985-2
• Publication Date: 2015-12-08T13:32:46Z
• Authors: Zhengqi Gu; Zhen Chen; Chengjie Feng; Taiming Huang; Zhendong Yang
• Keywords: 0202 electrical engineering, electronic engineering, information engineering; 02 engineering and technology

In light of the fact that computational results based on commonly used turbulence models are unsatisfactory, a modified LRN $${k-\varepsilon}$$ turbulence model is proposed. The modified concept includes the introduction of the total stress limitation idea and separation-aware model. With the help of this concept, the transport effects of total turbulent shear stress are taken into consideration and the boundary separation is detected. Thus, the model’s ability to simulate laminar-turbulent transition, which is an essential feature of the flow field around vehicles, is improved. The Ahmed model and its corresponding experimental data are introduced to validate and evaluate the modified LRN $${k-\varepsilon}$$ model. Several commonly used turbulence models are also introduced as comparisons. Computations are carried out by the ISIS-CFD flow solver. This work shows that predictions achieved by the modified LRN $${k-\varepsilon}$$ model give a better agreement with experimental data than other solutions.