PSI - Issue 57

Stéphan Courtin et al. / Procedia Structural Integrity 57 (2024) 4–13 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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• A radial thermal gradient, between the mock-up and the complementary ring. Fig. 2(a) illustrates the thermal loading #1 considered in this paper, where the temperature of the mock-up is constant through its whole thickness whereas the temperature of the complementary ring is cyclic (temperatures of both top and bottom oil circuits are sim ila r). • Both radial and axial gradients. Fig. 2(b) illustrates the thermal loading #2 considered in this paper, where there is a thermal gradient between the two faces of the central disk and there is also a thermal gradient between the central disk and the complementary ring (temperatures of both top and bottom oil circuits are similar). (a) (b)

Fig. 1. (a) PACIFIC facility (b) PACIFIC mock-up.

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Fig. 2. (a) Thermal loading #1 (b) Thermal loading #2.

Léopold et al. (2017) reported that, for the thermal loading #1, fatigue cracks propagated on both faces of the mock-up, with quite similar crack growth rates (see Fig. 3). Note that, for the thermal loading #2, only propagation on the bottom face, that is to say the one kept at 40°C (see Fig. 2(b)), was expected because of the thermal gradient between the two faces of the central disk. The corresponding experimental results, not reported by Léopold et al. (2017), will be presented later, with the numerical results.