Advances in concrete construction

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Numerical simulation of the effect of pipe size and foam inlet angle on mixing of cement slurry and foam

  • Leilei Wang (Department of Building Engineering, Zibo Vocational Institute)
  • Received : 2023.11.30
  • Accepted : 2024.09.11
  • Published : 2024.05.25
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Abstract

In order to improve the mixing effect of slurry-foam during the preparation of foam concrete, this study takes an SK static mixer as the mixing device, establishes a three-dimensional physical model and a theoretical calculation model, and numerically simulates the effects of different parameters such as foam inlet angle and pipe inner diameter on the mixing of cement slurry and foam under the given boundary conditions, so as to optimize the structure of this mixing device. The results show that when the pipe diameter of the mixer is larger than 60 mm, the phenomenon of backflow occurs in the pipe, which affects the mixing effect. The smaller the pipe diameter, the shorter the distance required to stabilize the cross-sectional average density and density uniformity index. When the foam inlet angle is different, the average density and density uniformity index of the radial cross-section have the same rule of change along the length of the pipeline, and all of them tend to stabilize gradually. At Y = 0.5 m, the average density basically stabilizes at 964 kg/m3 and remains stable until the outlet. At Y = 0.6 m, the density uniformity index basically stabilizes above 0.995 and remains stable until the outlet. Except for the foam inlet position (Y = 0.04 m), the foam inlet angle has little effect on the cross-sectional average density and density uniformity index. Under the boundary conditions given in this study, a pipe diameter of 40 mm, a foam inlet angle of 90°, and a pipe length of 700 mm are the optimal geometries for the preparation of homogeneous foam concrete with a density of 964 kg/m3 in this static mixer.

Keywords

Acknowledgement

The research described in this paper was financially supported by the Shandong Provincial Education System Government Sending Overseas Study Programme in 2022, Zibo Science and Technology Development Program Project (No. 2017kj010054), Shandong Province Vocational Education Teaching Reform Research Program (No. 2022047) and Shandong Province Art Science Project (No. 23YZ09230005)

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