Numerical Investigation of a Hydropower Tunnel: Estimating Localised Head-Loss Using the Manning Equation

Water

T.Staffan Lundström¹  Patrik Andreasson¹  L.Robin Andersson¹  J.Gunnar I. Hellström¹ 

[1] Division of Fluid and Experimental Mechanics, Luleå University of Technology, 97187 Luleå, Sweden;

关键词: head-loss;    case-study;    hydropower;    rock tunnel;    surface roughness;    ANSYS-CFX;   

DOI  :  10.3390/w11081562

来源: DOAJ

【 摘 要 】

The fluid dynamics within a water tunnel is investigated numerically using a RANS approach with the k- $\epsilon$ turbulence model. The computational model is based on a laser scan of a hydropower tunnel located in Gävunda, Sweden. The tunnel has a typical height of 6.9 m and a width of 7.2 m. While the average cross-sectional shape of the tunnel is smooth the local deviations are significant, where some roughness elements may be in the size of 5 m implying a large variation of the hydraulic radius. The results indicate that the Manning equation can successfully be used to study the localised pressure variations by taking into account the varying hydraulic radius and cross-sectional area of the tunnel. This indicates a dominant effect of the tunnel roughness in connection with the flow, which has the potential to be used in the future evaluation of tunnel durability. ANSYS-CFX was used for the simulations along with ICEM-CFD for building the mesh.

【 授权许可】

Unknown