Paper Conference

Proceedings of SimBuild Conference 2010: 4th conference of IBPSA-USA


Robust Eddy Viscosity Turbulence Modeling with Elliptic Relaxation for External Building Flow Analysis

Mirza Popovac
AIT Austrian Institute of Technology Österreichisches Forschungs- und Prüfzentrum Arsenal Ges.m.b.H. Energy Department, Sustainable Building Technologies Giefinggasse 2, 1210 Vienna, Austria

Abstract: This paper presents the application of the modified zeta − f turbulence model for the CFD analysis of the external building flows. The proposed modification, based on the elliptic relaxation eddy viscosity concept, enables very easy model implementation into a general purpose RANS-based CFD code, while keeping all advantages of the elliptic relaxation turbulence modeling approach: better physical description of the near-wall flow effects, and thus improved accuracy and reliability of the wall-bounded flow predictions. High robustness of the presented model modification, as well as its straightforward implementation (for the work in the present paper the model implementation in FLUENT is performed), makes it suitable for numerical analysis of the complex wall-bounded fluid flow and heat transfer engineering problems. In this paper the accent is on the external building flows, so the performance of this model and its implementation are tested on the realistic case of a flow around buildings in urban area. The obtained results enable the analysis of the flow effects that are characteristic to the external building flows, as the quality of the results is satisfactory, and the computation stability using the presented model was very good.
Pages: 497 - 505