Hydraulic operating conditions of an eddy tunnel outlet with an inclined shaft: Fid-Bau Portal

Hydraulic operating conditions of an eddy tunnel outlet with an inclined shaft

Khanov, N. V.

Abstract Model studies of the hydraulic operating conditions of an eddy tunnel outlet with an inclined shaft showed that:for regimes without delivery of air into the flow core with swirler parameterA=1.1 and with delivery of air for all values ofA, submergence of the outlet section of the conduit in the lower pool noticeably affects the size of the core and promotes the formation of a hydraulic jump zone along the tunnel;insignificant (in value) submergences of the exit section of the tunnel have little effect on the discharge capacity of the outlet (their differences is Δ=1.4% forA=0.6, Δ=2.71% forA=1.1, and submergence even increases the discharge of the outlet Δ=0.8% forA=0.83).delivery of air into the flow core has little effect on the discharge capacity of the structure, with the exception of the layout with a swirler withA=0.6 (Δ=4.31% forA=0.6, Δ=0.5%, and Δ=0.9% forA=1.1);considerable vacuums are observed for regimes without air in the flow core, the absolute values of which with increase ofA drop intensely from $ H_{fc} $=−4.5 m to $ H_{fc} $=−0.3m;delivery of air into the flow core markedly reduces the vacuums in it and their values are close to zero;with increase of swirler parameterA the area occupied by the flow at the end of the tunnel decreases;regimes without delivery of air into the flow core are the most favorable with respect to the conditions of the pressure distribution on the conduit walls;submergence on the downstream side does not lead to an increase of pressure on the conduit walls if the vacuum in the flow core increases simultaneously with this.