PSI - Issue 60

Sarath Chandran Nair S. et al. / Procedia Structural Integrity 60 (2024) 564–574 Sarath Chandran Nair S. / Structural Integrity Procedia 00 (2023) 000 – 000

568

5

c

Fig. 3. Strain variation in TBC segments from thermo-structural analysis (a) cylindrical segment; (b) AFC segment; (c) Nozzle first segment Based on the above analysis results, temperature and strain values were finalized for coatings/inner wall for hydro test/actual service condition of the thrust chamber and summarised in table2.

Table 2. Strain value from thermo-structural analysis

Maximum total strain Tensile

Region

Operating temperature Type of coating

Compressive

Cylindrical segment

Room temperature

Nickel

0.51%

--

Cylindrical segment

790 K

Nickel

--

0.65%

AFC segment

Room temperature

Nickel

0.05%

0.19%

AFC segment

790 K

Nickel

0.36%

0.50%

Convergent divergent segment

Room temperature

Nickel and Chromium

0.14%

0.10%

Convergent divergent segment

820K

Nickel and Chromium

0.20%

1.30%

4.2. Test plan Based on thermo-structural analysis, a test plan is formed for tensile and compressive strain conditions considering different operating conditions. Room temperature test is planned to simulate hydrotest condition of thrust chamber and 15 cycles of high temperature test in 5 batches of 3 test each. 15 cycles considered to simulate different test conditions of combustion chamber during its qualification and to ensure sufficient margin. The test plan is given in table 3 and 4.

Table 3. Qualification test plan for Nickel coating

Total stain

Test temperature

No. of cycles

Tensile

Compressive

Room temperature

0.6% 0.4%

0.2% 0.7%

1

790 K

15