Hydrodynamic and thermal behavior of tandem, staggered, and side-by-side dual cylinders

Physics of Fluids, Год журнала: 2024, Номер 36(1)

Опубликована: Янв. 1, 2024

This study investigates the impact of arrangement two cylinders on their flow-induced vibrations (FIV) and heat transfer behavior at a Reynolds number 100. Both were allowed to vibrate in degrees freedom (2DOF), encompassing streamwise transverse directions. The identical circular was varied across tandem (α = 0°), staggered 30°, 45°, 60°), side-by-side 90°) configurations, constant center-to-center distance 6D. heated fixed temperature observe forced convection under influence 2DOF FIV. To FIV, reduced velocity from Ur 0 (stationary cylinders) 14. Results unveiled cylinder response sensitivity, vibration transfer, with respect velocities arrangements. Tandem exhibited greatest for both cylinders. While lower drag experienced 2 (C-2), it escalated positioning. lock-in between 6 8 all arrangements, involving significant amplitudes. Maximum reached 6.07% maximum C-2 2.34% C-1. Distinct slender “figure-8” “oval-shaped” trajectories emerged, accompanied by diverse vorticity patterns wakes For α 60°, 75.3% 9.4% higher average Nusselt compared setup. Overall, pronounced correlation emerged hydrodynamic characteristics, evident through vibration, vortex shedding, number, distribution results.

Язык: Английский

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Numerical study on the flow around an elliptic cylinder with different aspect ratios in the subcritical regime using large eddy simulation

Physics of Fluids, Год журнала: 2024, Номер 36(1)

Опубликована: Янв. 1, 2024

The aerodynamic characteristics, flow fields, and patterns of the around an elliptic cylinder are investigated in this paper using large eddy simulation (LES). Reynolds number (Re) is fixed at 16 000 subcritical regime, aspect ratio (AR) varied from 0.6 to 1.4 with increment 0.2. numerical model applied initially validated for case AR = 1, showing good agreement previous studies. results indicate that both mean drag coefficient root square lift decrease increasing AR. total decomposed into two components: it indicates pressure dominant. primary separation point shifts backward within range 86.4°–92.3°. fields analyzed detail through time-averaged velocity profiles along three different axes. Additionally, two-dimensional (2D) three-dimensional (3D) visualizations wake also provided show vortex shedding mode characteristics structure ARs. This study supplements basic parameters details discusses influence a moderate Re regime has certain significance further optimization simplified human body efficient testing sport garments.

Язык: Английский

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Vortex-induced vibration and wake interference of two-degree-of-freedom elastically mounted elliptical cylinders in tandem at various spacing

Ocean Engineering, Год журнала: 2024, Номер 310, С. 118637 - 118637

Опубликована: Июль 8, 2024

Язык: Английский

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Numerical investigation of the aerodynamic performance and loss mechanism in a low bypass ratio variable cycle engine fan

Physics of Fluids, Год журнала: 2024, Номер 36(3)

Опубликована: Март 1, 2024

The aerodynamic performance of the variable cycle engine fan changes sharply during mode transition. Investigating variations flow structure and understanding loss mechanism are helpful in providing guidance for design. Three-dimensional models single bypass double compression systems established, static pressure is applied at stream outlet to simulate opening selection valve. characteristic band obtained by gradually increasing while maintaining specific values core pressure. Results show that overall configuration, without recirculation, almost identical conventional configuration throttling process. With increase pressure, shock wave trajectory tip leakage vortex move forward, thereby blockage region induced interaction between vortex. In addition, with reverse also calculated. recirculation causes operating point closer stability limit, reducing isentropic efficiency. Additionally, radial distribution axial velocity total leading inlet distortion driven stage. Furthermore, clarified modeling splitter conducting entropy generation analysis. sharp expansion could cause severe separation, curvature casing can effectively suppress viscous shear loss.

Язык: Английский

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Numerical study on hydrodynamic interaction characteristics of vortex-induced vibration of two side-by-side cylinders near the wall

Ocean Engineering, Год журнала: 2024, Номер 308, С. 118305 - 118305

Опубликована: Май 30, 2024

Язык: Английский

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Effect of radial inlet distortion on aerodynamic stability in a high load axial flow compressor

Physics of Fluids, Год журнала: 2024, Номер 36(10)

Опубликована: Окт. 1, 2024

Radial inlet distortion induced by boundary layer separation can significantly affect the aerodynamic performance of compressor. The effect radial on flow structure is numerically investigated in a high load axial determined experimental results at downstream generator. reveal that tip leads to reduction stall margin, whereas hub extends it. redistributes main toward undistorted region due obstructive lattice ring. deficit velocity with causes rotor operate higher incidence angle near casing, while alleviates blade loading. detailed three-dimensional field analysis indicates increased loading shifts trajectories both primary and secondary leakage leading edge, thereby expanding blockage region. Conversely, unloads region, reducing flow. Additionally, distortion, location line suction surface moves closer around trailing edge intensified.

Язык: Английский

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Numerical Analysis of Flow-Induced Transverse Vibration of a Cylinder with Cubic Non-Linear Stiffness at High Reynolds Numbers

Energies, Год журнала: 2024, Номер 17(7), С. 1776 - 1776

Опубликована: Апрель 8, 2024

Numerical calculations were performed to study the vortex-induced vibration (VIV) of a circular cylinder, which was elastically supported by springs linear and cubic terms. These simulations conducted at high Reynolds numbers ranging from 4200 42,000. To simulate cylinder’s motion associated aerodynamic forces, Computational Fluid Dynamics employed in conjunction with dynamic mesh capabilities. The numerical method initially verified testing it various grid resolutions time steps, subsequently, validated using experimental data. response nonlinearities investigated insights gained conventional system. This 2D revealed that both amplitude frequency vibrations are contingent on flow velocity. highest output achieved within lock-in region, where internal resonance occurs. In case hardening spring, beating observed lower end initial branch upper branch. displacement obtained for spring 27 mm, whereas nonlinear case, value 31.8 mm. More importantly, results indicate inclusion can substantially extend range wind velocities significant energy extraction through is achievable.

Язык: Английский

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Improving energy harvesting in flow-induced vibrations of multi-cylinder square arrays with vortex generators

Ocean Engineering, Год журнала: 2025, Номер 328, С. 121057 - 121057

Опубликована: Апрель 5, 2025

Язык: Английский

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Design optimization of axial slot casing treatment and blade in an axial compressor based on deep learning and reinforcement learning

Aerospace Science and Technology, Год журнала: 2025, Номер unknown, С. 110209 - 110209

Опубликована: Апрель 1, 2025

Язык: Английский

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Vortex-induced vibration characteristics of three cylinders with isosceles-triangle arrangements at low Reynolds number

Physics of Fluids, Год журнала: 2023, Номер 35(12)

Опубликована: Дек. 1, 2023

The geometric factors of multi-cylinders are one the affecting efficient energy capture vortex-induced vibration aquatic clean energy. Based on computational fluid dynamics numerical simulation method and overset mesh technology, an dynamic model VIV (vortex-induced vibration) two-dimensional elastic-supported cylinders was established. influence different vertex angles characteristics in isosceles-triangle arrangement investigated. results show that upstream cylinder is less affected by vertex-angle, peak value moves to left α-A*y curve downstream cylinders. As α increases, 8 shape negative direction flow direction, while move O gradually become narrow. vortex shedding mode mostly P + S mode, its amplitude related position cylinder's wake effect. lift drag coefficients α, dominant frequency independent change greatly Re. With increase Re, positive correlation between coefficient transverse displacement weakens.

Язык: Английский

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