Paper Details

The 6th stage steam turbine blade rotating with rotation velocity is deeply analyzed andanalysis is carried out as described below. In this paper the optimum point is found out to mountstrain gauges on the turbine blade for the combined centrifugal and vibratory stresses in steamturbine engines in order to capture the best modal response in the series of modes. In the first partmodal analysis was carried out for free-free vibration and there was good agreement between theexperimental and finite element analysis results and the deviation was found to be within 10%. In thesecond part the rotation velocity of 10000 RPM was given and vibratory stresses were calculatedusing harmonic analysis for 5 modes and corresponding centrifugal stresses were found for 5 modes.Then the relative percentages of stresses were located for different nodes on the blade on bothconcave and convex side of the blade to find optimal location on the blade. The optimum point onthe concave side was found at the node 10.93, 306.27,-21.749 at the point x, y, z respectively and atthis point 42%,26%,22%,15.3 and 7% of stress were captured and the optimum point on the convexside found at the node-7.709,312.83,0.844 at the point x, y, z respectively and at this point36.6%,19.8%,19.8%,25.14%,4.7% of stresses were captured.

Karthik C.1, Dr.P.V.Srihari, Dr.K.Ramachandra, “Optimization of Strain Gauge Location for Combined Centrifugal and Vibratory Stresses on Steam Turbine Blade”, International Journal of Advance Engineering and Research Development (IJAERD), Vol. 1, Issue 6, pp. 425-429, June 2014.