This study evaluated the influence of the geometry of ceramic specimens (disc vs. square plate) on the biaxial flexural strength (BFS) using an experimental set and finite element analysis (FEA). Leucite glass-ceramic blocks were used in the preparation of disc (D; n=14) and square plate (S; n=13) specimens with the same lower (tensile) surface area. The specimens were subjected to a piston-on-three-ball flexural test (ISO 6872:2008). To calculate the BFS of the S group, the specimen radius, indicated by the ISO 6872:2008 formula for discs, was replaced by half of the side length. FEA compared the pattern of stress distribution and the first principal stress between D and S specimens having the same and different lower (tensile) surface area. Student's t-test showed no difference (p=0.85) in the BFS between D (95.0±9.6 MPa) and S (84.3±10.3 MPa). FEA indicated a similar pattern of stress distribution, with almost no difference in the first principal stress of discs and square plates with the same lower (tensile) surface area. In the experimental condition investigated, square plate ceramic specimens can be used in piston-on-three-ball tests. For the calculation of the BFS, the specimen radius may be replaced by half side length of the square specimen.
Since the 1930s several conceptions of rainfall simulators were developed to perform runoff experiments, soil water infiltration, water erosion, persistence of phytosanitary products, etc. The uniformity of the rainfall generated is a parameter used to validate a rainfall simulator conception design. On this subject, this work aimed at identifying the wetted area uniformity of the rainfall generated by different sprinkler nozzles. The study was divided in two stages: experimental data collection; and, calculation of wetted area uniformity. In the first stage it was used an experimental bench to generate rainfall. The experiment was carried out under completely randomized, factorial 3 x 3 x 3 experimental design, with 27 treatments and six replications (162 experimental units). The treatments were a combination of three sprinkler nozzles (P1, P2 and P3), three sprinkler heights from the ground (1.1 m, 2.1 m and 3.1 m), and three water pressures (50 kPa, 100 kPa and 150 kPa). A mesh of 289 plastic collectors was used for stored the water volume of the rainfall generated from the experimental units. In the second stage, it was calculated the water distribution uniformity using the Christiansen Uniformity Coefficient (CUC) for the areas of 2.56 m², 1.44 m², 0.64 m² and 0.16 m². As a result, the higher the water pressure and sprinkler nozzle height and smaller the land plot, the greater the tendency to get CUC values classified as good or excellent. The sprinkler nozzle P1 showed the best results, so the conclusion is the wetted area uniformity is an important parameter to consider in the selection of sprinkler nozzles in the rainfall simulators design.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.