Abstract
The part-load performance of the gas turbine engine can be improved in VCE using variable geometry components. The VANT is one of the variable geometry components of the gas turbine engine to meet the power requirement at part load conditions by controlling the mass flow rate through the engine turbine section. However, the provision of the part clearances near the hub and casing endwall allows the leakage flow to occur. This leakage flow further increases the loss at the exit of the turbine nozzle vane. The provision of the pivot to hold the vane in endwalls creates a blockage to the leakage flow and changes the flow field of the turbine nozzle passage. As the operating Reynolds number of the LPT is of the order of 105, flow experiences a transition between laminar and turbulent flow regimes. Hence, the present study is conducted with two different turbulent models, i.e., widely used SST k-ω and SST γ-Reθ, to analyze the part clearance flow field. The flow field is analyzed in the present study using streamlines plotted at different streamwise planes superimposed on non dimensional vorticity contours, and total pressure loss coefficient (Cpt) at the exit of the turbine nozzle vane.
