PSI - Issue 17

Pedro J. Sousa et al. / Procedia Structural Integrity 17 (2019) 812–821 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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Table 1. Parameter values used for viscosity definition using Reynolds Stress model Parameter Value Cε 1 1.44 Cε 2 1.92 C 1 1.8 C 2 0.6 C 1 ’ 0.5 C 2 ’ 0.3 C μ 0.09

Where the first two relate to the dissipation rate, the next four to the linear pressure-strain model and the last to turbulent viscosity. This computational model is especially suited for flows with strong rotation and swirling motions [12,13]. The solid domain was modeled using FEA with the material parameters defined in the previous section. The model considered two main loads: the centrifugal force and the fluid-structure interaction. The first was defined for the same angular speed and axis as the motion of the rotational domain, and the latter was considered for the whole contact

surface. Finally, the inner cylinder surface of the hub was defined as the fixed support. The transient analysis was solved with steps of 0.01 seconds for a total of 1.00 second.

3.3. Results For the present analysis, the most interesting results relate to the structure’s mechanical response and not the fluid’s response. Nonetheless, the air velocity in stationary frame at the final instant of the CFD simulation is also shown in Fig. 8 as an example of the kind of results that were obtained for the fluid domain.

Fig. 8. Velocity in stationary frame obtained as a result of the CFD simulation at instant 1.0 s

Among the different parameters of the mechanical response where the deflection along the Z-axis is the most representative, Fig. 9, having a maximum displacement of 2.256 mm on the tip. The other displacements, along X and Y, are shown in Fig. 10.