Analysis of design modification to labyrinth seal of last stage blade in a geothermal turbine

摘要

A modification to the original design of the labyrinth seal channel of last stage blade i na 110 MW geothermal turbine is analysed. Based on the design modification, substantial change of the present flow patterns can be obtained as concluded from a CFD study. The new design has the purpose of reducing the continuos erosion of tneons, which has been detected through inspections during major overhauls of the turbine. The modification here in proposed impacts mainly on the reduction of the volumetric steam flow rate that exits through the channel and the moisture catcher of the last stage L-0. This induces a 30