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A 2-D numerical wave tank (NWT) was applied for solving the interaction between a solitary wave and a moving circular cylinder. The cylinder was placed at various positions from the tank bed floor. The cylinder can move at a constant horizontal velocity towards the solitary wave. The collision between a solitary wave and a moving cylinder is investigated at various conditions. A total of fifteen cases were studied. Ten different numerical simulations were used, including five submergence depths and two different moving velocities. The other five different numerical simulations were studied when the cylinder was unmoved in the NWT for comparing wave-structure interaction results between the moving and unmoved cylinders. The numerical results were obtained by calculating Reynolds-Averaged Navier-Stokes (RANS) equations and the volume of fluid (VOF) equations. Two different codes (User-Define-Function-UDF) were used for the generation of a solitary wave by moving a wave paddle and traveling cylinder in the NWT. The dynamic mesh method was applied for recreating mesh. First, the ability of CFD codes to generate a solitary wave by using wave paddle movement and the hydrodynamic forces of a moving cylinder were validated by numerical results. Further, the free-surface elevation and hydrodynamic forces were considered at various conditions. The numerical results show that moving cylinder velocity and the space between the cylinder and the tank bed floor have significant effects on surface displacement and hydrodynamic forces.

A three-dimensional T-shaped flexible beam deformation was investigated using model experiments and numerical simulations. In the experiment, a beam was placed in a recirculating water channel with a steady uniform flow in the inlet. A high-speed camera system (HSC) was utilized to record the T-shaped flexible beam deformation in the cross-flow direction. In addition, a two-way fluid-structure interaction (FSI) numerical method was employed to simulate the deformation of the T-shaped flexible beam. A system coupling was used for conjoining the fluid and solid domain. The dynamic mesh method was used for recreating the mesh. After the validation of the three-dimensional numerical T-shaped flexible solid beam with the HSC results, deformation and stress were calculated for different Reynolds numbers. This study exhibited that the deformation of the T-shaped flexible beam increases by nearly 90% when the velocity is changed from 0.25 to 0.35 m/s, whereas deformation of the T-shaped flexible beam decreases by nearly 63% when the velocity is varied from 0.25 to 0.15 m/s.

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The highly viscous liquid (glycerin) sloshing is investigated numerically in this study. The full-scale membrane-type tank is considered. The numerical investigation is performed by applying a two-phase numerical model based on the spatially averaged Navier-Stokes equations. Firstly, the numerical model is validated against the available numerical model and a self-conducted experiment then is applied to systematically investigate the full-scale sloshing. In this study, two filling levels (50% and 70% of the tank height) are considered. The fluid kinematic viscosity is fixed at a value being 6.0 × 10−5 m2/s with comparative value to that of the crude oil. A wide range of forcing periods varying from 8.0 s to 12.0 s are used to identify the response process of pressures as well as free surface displacements. The pressures are analyzed along with breaking free surface snapshots and corresponding pressure distributions. The slamming effects are also demonstrated. Finally, the frequency response is further identified by the fast Fourier transformation technology.

In this study, the effects of wind on an Eastern Red Cedar were investigated using numerical simulations. Two different tree models were proposed, each with varying bole lengths and canopy diameters. A total of 18 cases were examined, including different canopy diameters, bole lengths, and wind velocities. Using computational fluid dynamics (CFD) methods, the drag force, deformation, and stress of the tree models were calculated under different wind velocities and geometric parameters. A one-way fluid–structure interaction (FSI) method was used to solve the deformation of the tree. Additionally, velocity and pressure distribution around the tree were obtained. The results indicate that wind velocity and geometric parameters of the tree have a significant impact on deformation, drag force, and stress. As wind velocity increases from 15 to 25 m/s, the force on the tree increases substantially. The results also show that the diameter of the canopy has a bigger effect on stress and strain than the bole length. This study provides insights into tree behavior under wind loading for urban planning and design, informing optimal tree selection and placement for windbreak effectiveness and comfortable environments.

Thermal conductivity is an important parameter that expresses the heat transfer performance of a heat transfer fluid. Due to their low thermal conductivity, conventional heat transfer fluids (e.g. water, oil, ethylene glycol mixtures) restrict the enhancement of performance and compactness in heat exchangers used in the electronic, automotive, and aerospace industries. Nanofluids are functional liquid suspensions including particles that are smaller than 100 nm. These smaller sized particles allowed forming uniform and stable suspensions. The most well-known nanoparticles are Al2O3, CuO, TiO2, each of which is used, together with the base fluids of water and ethylene glycol, in the experimental work of many researchers. Across the range of particle sizes and types of base fluids, the enhancement of thermal conductivity has been achieved under all experimental conditions with these nanoparticles. The nanofluids provide higher heat transfer enhancement than existing techniques. With some improved properties, they have extensive potential application for concentrating heat transfer performance in a variety of systems. Forced convection flows of nanofluids containing of water with TiO2 and AI2O3 nanoparticles in circular and noncircular tubes with constant wall temperature are investigated numerically in this paper. A single-phase numerical model having three-dimensional equations is solved with either constant heat flux or temperature dependent properties to determine the hydrodynamics and thermal behaviors of the nanofluid flow by means of a CFD program for the water flow in circular and noncircular tubes. An intensive literature review on the determination of the physical properties (k, μ, ρ, Cp) of nanofluids is given in the paper. The software package ANSYS Fluent was employed in the numerical study. Investigated tubes were plotted in the SolidWorks program and were imported to ANSYS Geometry. After the investigated tubes were imported to ANSYS Geometry, they were forwarded for meshing in the ANSYS Meshing program. The mesh influences the accuracy, convergence, and speed of the solution. Furthermore, the time required to create a mesh model often represents a significant portion of the time required to acquire results from the solutions; this means that the better and more automated the meshing tools, the better the solution. The numerical model is validated by means of a CFD program to compare the experimental smooth tube data as a case study and it is also solved in the CFD program for noncircular tubes as a simulation study. Velocity, temperature and pressure distributions are shown in the paper. Morever, the values of experimental and numerical are compared with each other in terms of convective heat transfer coefficients and pressure drops. Besides this, the effects of the presence of nanofluids and noncircular tubes on the heat transfer characteristics are investigated in detail.