PSI - Issue 50

Diana D. Popova et al. / Procedia Structural Integrity 50 (2023) 236–250 Popova, Popov, Samoylenko/ Structural Integrity Procedia 00 (2022) 000 – 000

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The minimum displacements in the radial direction are observed in the leading edge region, which is explained by the lower temperature (due to the presence of two rows of cooling perforations), and also due to the greater thickness in the leading edge region, there is less tension from centrifugal force. The maximum displacements are observed on the SS, closer to the trailing edge, which is explained by its higher temperature and smaller thickness. 6. Tip clearance real form The TC value at the points is obtained by adding the stator displacement and the mounting gap and subtracting the total displacements of the rotor and blade for eight points along the profile on the periphery according to the formula (1):

i i M C R B      , i i

(1)

where M is the size of the mounting gap; C i – case movement at a certain point; R i are rotor displacements; B i - blade displacement. Using formula (2), we obtained the TC relative value for eight points along the blade profile at the periphery:

   i i

,

(2)

a 

where i  is the real TC value, a  is the TC average value for all eight points. Using formula (3), the reduced TC values at eight points along the blade profile at the periphery were obtained, if the average TC value is 0.5 mm, which is the average and is used in the turbine RB three-dimensional gas-dynamic analysis. 0.5 mm *    i i , (3) i  – TC relative value. Figure 7 shows the reduced TC value non-uniformity graph at eight points along the blade profile at the periphery. where

Fig. 7. The reduced tip clearance value along the blade profile on the periphery.