PSI - Issue 37

Alexandre Fragoso et al. / Procedia Structural Integrity 37 (2022) 533–539 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

536 4

b

Fig. 3. (a) Overall view of the double-cyclone modelled (dimensions inmeters ); (b) Thicknesses of the steel sheets that compose the cyclones.

The external loads applied are gravity (weight of the structure itself) and temperature. The interior temperature of each section is impossible to record, but the entry and exit temperatures of the gases are known, and the external temperatures of the structure can be measured. Therefore, points outside the structure were selected to collect the temperatures, as indicated in Fig. 4; for this purpose, a thermographic pistol was used. Observing the temperature values recorded, it is possible to infer that the temperature distribution is not symmetrical and can vary significantly in the same section (Fig. 4). These variations can be explained by possible defects in the coating layers and the flow of matter inside the cyclone. Nevertheless, an approximate temperature for the outer structure of 100°C can be assumed.

Fig. 4. Identification of the points where the external temperatures were measured. The temperature distribution defined accordingly with the measured points.

The cyclones have three attachment points to the preheating tower structure (Fig. 5). Therefore, fixed supports were used in the three circular crowns that connect the cyclones to the structure. In addition, the mesh parameters identified in Fig. 5 were used, and an internal 150 mm thick concrete slab anchored to the interior framework was simulated (Fig. 6). This modelling was performed to determine the linear elastic structural behaviour of the equipment with the refractory material coating (concrete) applied. An internal uniform temperature of 750°C was assumed.