PSI - Issue 27

Aldias Bahatmaka et al. / Procedia Structural Integrity 27 (2020) 6–13 Bahatmaka et al./ Structural Integrity Procedia 00 (2019) 000 – 000

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(a)

(b)

Fig. 5. Wind loads on ship simulation: (a) Longitudinal force for LNG carriers, and (b) Pressure contours on LNG carrier at the angle of 30 degrees (Wnek et al., 2015).

Table 1. Wind force coefficients according to different thickness of the first prism layer (Wnek et al., 2015). C X [-] C Y [-]

C N [-] -0.054 -0.047 -0.060 -0.053 -0.050 -0.050 -0.050 -0.046

EXP

-1.100 -0.540 -0.490 -0.500 -0.500 -0.480 -0.450 -0.500 -0.540

-1.100 -0.680 -0.800 -0.760 -0.690 -0.690 -0.700 -0.690 -0.680

CFD (no prism) CFD (y + =0.05) CFD (y + =0.1) CFD (y + =0.5) CFD (y + =1) CFD (y + =2) CFD (y + =10) CFD (y + =30)

-0.040 Table 1. presents results determined by the wind tunnel and CFD code using a tetrahedral mesh with various thicknesses of the first prism layer. In comparison to the experimental measurements, the numerical data varied slightly. The most reasonable result occurred for y + =0.1 . The significant difference in magnitude of the forces between wind tunnel tests (EXP) and CFDtetra y + results by about 40% for some angles of incidence has not a clear explanation.

3.3. Evaluation of wind loads on high-rise building analysis

Fig. 6. The cross-ventilated building model studied (Cheung et al., 2011).

Several validation exercises were performed. As almost all the experimental measurements of cross-ventilation available in the literature were taken on low-rise structures, we had to con fi gure our CFD accordingly in the model validation exercise. The cross-ventilated building model used in the wind tunnel experiment was replicated by the CFD (Cheung et al., 2011). The experimental model was sized 300 mm × 300 mm × 150 mm (length × width × height. The building height served as the reference length scale H). Two small openings with dimensions 60 mm × 30 mm (width × height) were installed in the middle of both the windward and the leeward walls. The origin was assigned in the middle of the win dward facade on the floor (Fig. 6).