Optimization of the Internal Circulating Fluidized Bed Using Computational Fluid Dynamics Technology

Water jets are widely used in seabed scouring and desilting applications. In the present work, dedicated tests have been conducted using a jet scour model test platform and sand beds containing grains with different sizes. The FLOW-3D simulation software has also been used to tackle the problem form a numerical point of view. The boundary conditions of the simulation have been optimized to reduce the gap between the numerical results and the outcomes of the experimental tests. Scour area calculation has been based on a RNG k-ε Turbulence model. Moreover, the FAVOR (Fractional Area Volume Obstacle Representation) technology has been selected for grid division to make the simulation results more accurate. Jet scours with inclination angles of 10-20°have been simulated. It has been found that jet scouring is greatly affected by the environmental water flow, that is, water flow can weaken the scouring capacity of the jets.

Section: Numerical Simulationmentioning

confidence: 99%

Simulation of Seabed Erosion Produced by an Inclined Jet

Zhang¹,

Gong²,

Zhang³

et al. 2023

“…The FSI system, which can be calculated using fluid and structure displacements, was influenced by the displacement vector's structure and fluid field (in displacement form) [15]. According to the continuity conditions of compressible fluid, the dynamic balance of fluid in each direction can be expressed as follows (where K is the modulus of compressibility of the fluid) [16,17]:…”

Section: Model Of Fsimentioning

confidence: 99%

Analysis and Optimization of Flow-Guided Structure Based on Fluid-Structure Interaction

Cui¹,

Wang²,

Ru³

et al. 2023

Gases containing sulfur oxides can cause corrosion and failure of bellows used as furnace blowers in high-temperature environments. In order to mitigate this issue, the behavior of an effective blast furnace blower has been examined in detail. Firstly, the Sereda corrosion model has been introduced to simulate the corrosion rate of the related bellows taking into account the effects of temperature and SO 2 gas; such results have been compared with effective measurements; then, the average gas velocity in the pipeline and the von Mises stress distribution of the inner draft tube have been analyzed using a Fluid-Structure Interaction model. Finally, the semi-closed internal corrosion environment caused by a 5 mm radial gap between the inner draft tube and the bellows has been considered. The gas flow rate in the residential space has been found to be low (0.5 ms-this value leads to a stable semi-closed internal corrosion environment for exhaust gas exchange); water phase in the exhaust gas is prone to accelerate the corrosion rate. On this basis, a bellows with an optimized inner draft tube has proposed, which includes corrosion-resistant honeycomb buffer rings.

“…Numerical simulations such as computer-aided engineering (CAE) [9][10][11][12] and computational fluid dynamics (CFD) [13][14][15] are used instead of experiments, greatly saving costs of time and money. Scholars have used CFD [16][17][18][19][20][21] and CAE [22][23][24][25] methods in the study of nanofluids [26,27], bionic engineering [28,29], engineering architecture [30], and other fields. Computer-aided simulations enable the observation of many details that cannot be captured by experiments, allowing for more in-depth studies.…”

Section: Introductionmentioning

confidence: 99%

The Nest of Torquigener Albomaculosus: Fluid-Dynamic Aspects and Potential for Bio-Inspired Engineering

Zhao¹,

Wang²,

Tie³

et al. 2023

Torquigener albomaculosus, also known as the white-spotted pufferfish, is known for creating circular nests in the underwater sand as part of the mating ritual. The nests are built by the males to attract females through the nest's impressive design and related ability to gather fine sand particles. As the fluid-dynamic processes associated with these unique nests are still almost completely unknown, in the present study, an analysis has been conducted to investigate how the geometric parameters related to the nest design influence the fluid velocity in its center. For this reason, a geometric model of the nest consisting of 24 channels, where each unit channel can be described by three strips of broken lines, has been introduced, and a multivariate analysis has been implemented to determine the relative weight of each considered parameter. In particular, the "optimal" combination of parameters has been obtained by means of an orthogonal design approach. We show that these bio-nest structures also display a potential for significant application in marine litter collection, or for use as a buffer against the waves in offshore areas.