Straight Cylinder Research Articles

Heat Transfer in Carbon-Nanotube Dispersions: A Simulation Study of the Role of Nanotube Morphology and Connectivity

Simulation of the behavior of carbon nanotubes (CNTs) can become a very challenging task considering their complicated shape and large aspect ratio. This study aims to elucidate the role of CNT shape, length, and connectivity during heat transfer in CNT dispersions through a three-dimensional (3D) simulator. Three characteristic shapes for the CNTs are considered, namely, straight, moderately curved, and strongly curved. The results reveal that the commonly used assumption of viewing CNTs as straight cylinders leads to significant overestimation of the overall medium conductivity. The CNT length has an important effect on the nanofluid conductivity for all types of CNT shapes considered here. In addition, use of CNTs with higher conductivity than a certain value appears to have no further beneficial effect, thus relaxing the need for extremely pure or single-wall CNTs. On the contrary, the conductivity remains a strong function of the CNT concentration and may be even increased upon organization of CNTs into loose clusters. The overall approach and concept can be extended to CNT composites in a straightforward manner.

Turbulent flow around convex curved tandem cylinders

Turbulent flow around curved tandem cylinders has been studied for the first time, by means of direct numerical simulation. The convex configuration was used, with a nominal gap ratio of $L/D = 3$ and a Reynolds number of 3900. Along the span, the flow regimes vary from alternating overshoot/reattachment to co-shedding. Three distinct Strouhal numbers coexist in the flow that are tied directly to different tandem cylinder flow regimes. This result differs substantially from convex curved tandem cylinders at a transitional Reynolds number, where only a single dominant frequency is found. All regimes exhibit some degree of instability, so that the flow can be considered multistable. A mode switch from alternating overshoot/reattachment to symmetric reattachment is found. Complex interactions are observed between the primary instability, the shear layer instability and the flow mode alterations. As opposed to previous investigations with single and tandem straight cylinders in the subcritical flow regime, our results indicate that there may be direct feedback from the primary instability to the shear layer instability. The downdraft region in the gap exhibits slow meandering, and may travel upstream and amplify the shear layer instability, causing early transition in the gap shear layer. This downdraft is governed by the slow modulations of the vortex formation region in the lower gap, meaning that the vortex dynamics of this region may indirectly influence the shear layer instability higher up in the gap.

The bending of 3D-printed bio-inspired sandwich panels with wavy cylinder cores

Beetle Elytron Plates (BEPs) represent a new class of biomimetic sandwich cores with excellent mechanical properties inspired by the microstructure of the beetle elytra. The cores have a hexagonal centre-symmetric configuration with through-thickness cylinders in the unit cell. In this work, we describe the behaviour of sandwich panels with novel BEP core configurations possessing wavy cylinders under four-point bending tests. Full-scale simulations are also carried out to validate the experimental data. The results show that all the sandwich panels produced with face skins adhesively bonded have material failure earlier than the adhesive bond failure. BEPs with wavy cylinders have larger peak loads compared to those with straight cylinders, and all BEPs show higher peak loads than those of sandwich panels with classical hexagonal honeycombs. Additionally, all the BEPs exhibit an enhanced ductility compared to honeycomb sandwich panels.

An Eulerian formulation for the computational modeling of phase-contrast MRI.

Computational simulation of phase-contrast MRI (PC-MRI) is an attractive way to physically interpret properties and errors in MRI-reconstructed flow velocity fields. Recent studies have developed PC-MRI simulators that solve the Bloch equation, with the magnetization transport being modeled using a Lagrangian approach. Because this method expresses the magnetization as spatial distribution of particles, influences of particle densities and their spatial uniformities on numerical accuracy are well known. This study developed an alternative method for PC-MRI modeling using an Eulerian approach in which the magnetization is expressed as a spatially smooth continuous function. The magnetization motion was described using the Bloch equation with an advection term and computed on a fixed grid using a finite difference method, and k-space sampling was implemented using the spoiled gradient echo sequence. PC-MRI scans of a fully developed flow in straight and stenosed cylinders were acquired to provide numerical examples. Reconstructed flow in a straight cylinder showed excellent agreement with input velocity profiles and mean errors were less than 0.5% of the maximum velocity. Numerical cases of flow in a stenosed cylinder successfully demonstrated the velocity profiles, with displacement artifacts being dependent on scan parameters and intravoxel dephasing due to flow disturbances. These results were in good agreement with those obtained using the Lagrangian approach with a sufficient particle density. The feasibility of the Eulerian approach to PC-MRI modeling was successfully demonstrated.

A Pseudo-Spectral Method for Wall Shear Stress Estimation from Doppler Ultrasound Imaging in Coronary Arteries.

The Wall Shear Stress (WSS) is the component tangential to the boundary of the normal stress tensor in an incompressible fluid, and it has been recognized as a quantity of primary importance in predicting possible adverse events in cardiovascular diseases, in general, and in coronary diseases, in particular. The quantification of the WSS in patient-specific settings can be achieved by performing a Computational Fluid Dynamics (CFD) analysis based on patient geometry, or it can be retrieved by a numerical approximation based on blood flow velocity data, e.g., ultrasound (US) Doppler measurements. This paper presents a novel method for WSS quantification from 2D vector Doppler measurements. Images were obtained through unfocused plane waves and transverse oscillation to acquire both in-plane velocity components. These velocity components were processed using pseudo-spectral differentiation techniques based on Fourier approximations of the derivatives to compute the WSS. Our Pseudo-Spectral Method (PSM) is tested in two vessel phantoms, straight and stenotic, where a steady flow of 15mL/min is applied. The method is successfully validated against CFD simulations and compared against current techniques based on the assumption of a parabolic velocity profile. The PSM accurately detected Wall Shear Stress (WSS) variations in geometries differing from straight cylinders, and is less sensitive to measurement noise. In particular, when using synthetic data (noise free, e.g., generated by CFD) on cylindrical geometries, the Poiseuille-based methods and PSM have comparable accuracy; on the contrary, when using the data retrieved from US measures, the average error of the WSS obtained with the PSM turned out to be 3 to 9 times smaller than that obtained by state-of-the-art methods. The pseudo-spectral approach allows controlling the approximation errors in the presence of noisy data. This gives a more accurate alternative to the present standard and a less computationally expensive choice compared to CFD, which also requires high-quality data to reconstruct the vessel geometry.

Flow dynamics and heat transfer characteristics of flows past a zigzag cylinder in a bounded domain

A comprehensive numerical and experimental study is conducted to investigate the flow dynamics and heat transfer characteristics of flows past a novel wavy-axis circular cylinder placed symmetrically between two parallel walls. For comparison, the flow past a corresponding straight-axis cylinder within the same bounded domain is also studied. The investigations were primarily conducted at Reynolds numbers of 626 and 680, based on the average velocity and diameter of the cylinder, with a blockage ratio of 0.42, based on the widest area of the channel. At these flow conditions, the straight cylinder expectedly showed a “reverse” von Kármán type wake. However, the special zigzag cylinder showed fundamentally distinct flow patterns at the wake leading to a significant drag reduction and a heat transfer enhancement, compared to the performance of the straight cylinder. The pressure drop of the zigzag cylinder is 14 % and 19.4 % lower than that of the straight cylinder, with a higher convective heat transfer coefficient of 24 % and 9 %, respectively, for Reynolds numbers of 626 and 680. The substantial drag reduction is attributed to the formation of steady flow pattern in the wake indicating the suppression of unsteady vortex shedding. The heat transfer enhancement was mainly caused by the formation of elongated vortical structures principally aligned in the streamwise direction. The creation of these streamwise vortex tubes tends to more efficiently mix the fluid between the near-wall area and the core region of the channel than the near-planar vortex shedding associated to the straight cylinder. It was shown that the 3D shape of the zigzag cylinder generates a spanwise velocity component, which results in the creation of a dominant streamwise vorticity component that eventually develops into sustained vortex tubes.

Resonant Absorption of Standing Magnetohydrodynamic Waves in Coronal Loops in the Absence of Directional Symmetry: The Effect of Plasma Flow

The oscillation properties of standing magnetohydrodynamic (MHD) waves in coronal loops have been investigated. The coronal loop is modeled as a straight cylinder with a purely longitudinal magnetic field and a field-aligned plasma flow. The loop model includes an inhomogeneous transitional layer that causes the wave to be resonantly damped. Our aim is to determine the damping rate of the standing MHD waves in flowing loops, in which the directional symmetry of the loop has been broken due to the presence of plasma flow. To do this, the standing wave has been considered as the superposition of two propagating waves with opposite directions of propagation but the same oscillation frequency and damping rate. Due to the absence of directional symmetry in the loop, it seems that the propagating components of the standing wave cannot have the same oscillation frequency and damping rate. To overcome this problem, in the perturbation method employed, we let both the oscillation frequency and damping rate be perturbed. As the flow speed increases the oscillation frequency of the standing wave decreases but its damping rate increases. As a result, the ratio of the oscillation frequency to the damping rate of the standing wave becomes a more decreasing function of the flow speed. The flow is an important quantity in determining the effectiveness of resonant absorption. In flowing loops even in the case of a thin transitional layer, resonant absorption can result in a damping rate on the order of the period time, which is in agreement with observations.

Resonant absorption of standing MHD waves in coronal loops in the absence of directional symmetry: the effect of weak plasma flow

ABSTRACT The oscillation properties of standing magnetohydrodynamic waves in coronal loops has been investigated. A coronal loop is modelled as a straight cylinder with purely axial magnetic field and field aligned plasma flow. The loop model includes an inhomogeneous transitional layer that causes the wave to be resonantly damped. Our aim is to obtain the solution describing a resonantly damped standing kink wave in a flowing loop with the directional symmetry of the loop being broken due to the presence of plasma flow. In the absence of damping the standing wave is a superposition of two waves propagating in the opposite directions that have the same frequency but different wavenumbers. However, the same approach cannot be used when there is damping because the decrements of the two propagating waves are different. We suggest that in the case of relatively weak flow, as is the case in coronal loops, the effect of flow on the decrements can be neglected. Then the decrements of the two waves are the same and the solution describing the damped standing kink wave is a superposition of two resonantly damped propagating waves.

Effect of friction stir processing parameters on mechanical properties of Al8011/CeO2/SiC/RHA metal matrix composite

ABSTRACT In this research work, the FSP route opted to fabricate the metal matrix composite (MMC) on the surface of an aluminium 8011 alloy sheet by incorporating different volumetric compositions of silicon carbide (SiC) and cerium oxide (CeO2) with a constant 5% volumetric composition of rice husk ash (RHA). The fabrication process was based on the L27 design of experiments. Taguchi-coupled grey relational analysis (GRA) was employed for process optimisation with four factors: tool rotation speed, tool travel speed, reinforcement volume, and tool type, each with three levels, while tensile strength and micro-hardness were taken as the response variables. The optimal parameter setting for fabrication of Al8011 MMC was 600 RPM of rotational speed (level 3), 20 mm/min travel speed (level 1), reinforcing volume% (level 2), and straight cylinder pin profile (level 1). The corresponding values of the optimised response variables were 181.91 MPa tensile strength and 139.09 Hv microhardness. The tensile strength and microhardness of base Al8011 were found to be 175.77 MPa and 92.72 Hv, respectively. Meanwhile, the microstructure of the optimal FSP-processed MMC was analyzed through the scanning electron microscopy (SEM) technique, which confirmed a homogeneous distribution of reinforcing agents and refined grain structure.

The engineering elastic constants of bio-inspired sandwich cores with wavy cylinders

Beetle Elytron Plates (BEPs) represent a new class of biomimetic sandwich cores with excellent mechanical properties and inspired by the internal structure of the beetle elytra. The cores have a hexagonal centre-symmetric configuration with through-thickness cylinders in the unit cell. The present work describes the behaviour of the engineering elastic constants of an evolution of these BEP topologies that feature cylinders with waviness. These BEP core configurations are simulated using Finite Element models, with periodic boundary conditions for volumetric homogenization. The models are then used to perform a parametric analysis against the geometry characteristics of the new cellular configurations. This work further explores the potential design space of BEP cellular metamaterials by altering the geometry of the trabeculae and facilitates further investigation into the mechanical properties of these new BEP topologies with wave-shaped units. Although – and as expected - the specific nondimensional out-of-plane tensile modulus has values here close to unity, BEP topologies with out-of-plane wave-shaped cylinders show enhanced in-plane moduli values than classical straight cylinder configurations, except for the Young's modulus of MBEP cores with only one semi-wave. The same trend is observed for the nondimensional Young's modulus of EBEP configurations, whereas the situation is opposite for the MBEP topologies. The nondimensional out-of-plane shear modulus decreases for both EBEP and MBEP configurations compared to the straight cylinder cores.

A novel anchor method for large tonnage CFRP cable: Anchorage design and full-scale experiment

This study introduces a novel three-segment CFRP cable anchorage to address stress concentration challenges in CFRP cable anchors. The anchorage features a continuously varying inner cone angle along the anchor length to prevent excessive radial stress on the CFRP cable. The radial stress distribution is theoretically analyzed, followed by a numerical simulation design using the Tsai-Wu failure criterion and the anchor system's equivalent stiffness as evaluation indices. The results demonstrate a 47.06 % and 45.73 % reduction in the radial stress peak of the novel anchorage compared to the inner cone and inner cone + straight cylinder anchorage, respectively. Importantly, beyond an anchor length 23 times the equivalent diameter of the CFRP tendon, increasing length has a marginal impact on anchor efficiency but diminishes equivalent stiffness. Positive effects are observed by increasing the inner cone segment proportion and adjusting the inner cone angle within the 2° to 4° range. Conversely, increasing the bonding medium thickness reduces anchor efficiency and equivalent stiffness. Experimental verification indicates the anchor system achieving 99.83 % anchor efficiency. Moreover, the axial strain of CFRP tendons in the anchor zone exhibits a linear trend along the anchor length, with test stresses at corresponding positions consistent with FE calculation results.

Simulation study of partial discharge UHF signal propagation characteristics in GIS

Insulation defects inside a Gas Insulated Switchgear (GIS) can generate partial discharges, and the current pulses caused by them can excite ultra-high frequency (UHF) electromagnetic waves. To study the attenuation characteristics of UHF signal propagation in GIS, simulation models of the straight cylinder, insulator, L-type, and T-type structures are established by CST simulation software. Then the propagation characteristics of partial discharge UHF signal are studied and analyzed. The simulation results show that the electromagnetic wave propagates in each structure inside the GIS with different degrees of attenuation. When passing through insulators continuously, the first insulator has the most serious attenuation; when passing through T-shaped structures, the attenuation of T-shaped vertical branches is more serious than linear branches.

Dissipative Instability of Magnetohydrodynamic Sausage Waves in a Compressional Cylindrical Plasma: Effect of Flow Shear and Viscosity Shear

The shear flow influences the stability of magnetohydrodynamic (MHD) waves. In the presence of a dissipation mechanism, flow shear may induce an MHD wave instability below the threshold of the Kelvin–Helmholtz instability, which is called dissipative instability. This phenomenon is also called negative energy wave instability because it is closely related to the backward wave, which has negative wave energy. Considering viscosity as a dissipation mechanism, we derive an analytical dispersion relation for the slow sausage modes in a straight cylinder with a discontinuous boundary. It is assumed that the steady flow is inside and dynamic and bulk viscosities are outside the circular flux tube under photospheric condition. When the two viscosities are weak, it is found that for the slow surface mode, the growth rate is proportional to the axial wavenumber and flow shear, consistent within the incompressible limit. For a slow body mode, the growth rate has a peak at a certain axial wavenumber, and its order of magnitude is similar to surface mode. The linear relationship between the growth rate and the dynamic viscosity established in the incompressible limit develops nonlinearly when the flow shear and/or the two viscosities are sufficiently strong.

Numerical Simulations of Supersonic Exhaust Diffuser At Various Operating Conditions

A numerical study was carried out to determine starting characteristics of a straight cylindrical supersonic exhaust diffuser of a high altitude simulation of high expansion rocket nozzle. The starting conditions of the supersonic exhaust diffuser are numerically simulated for contour nozzle of exit-to-throat area ratio of 21.77, diffuser diameter-to-nozzle throat area ratio of 23.36, and diffuser length-to-diameter ratio of 15. The evacuation performances of supersonic exhaust diffuser at various operating conditions are investigated with help of the Mach contour plots. The Mach variations along the centre line and wall of the diffuser indicate the location of the shock and flow characteristics. Validation of numerical simulation is carried out with experimental data and shows a good agreement between them. Flowfield inside the straight cylinder supersonic exhaust diffuser is presented out for stagnation to ambient pressure ratio of 5.5 - 28. The nozzle is started at the stagnation to ambient pressure ratio of about 17. The straight cylindrical supersonic exhaust diffuser is started at the stagnation pressure to ambient pressure ratio of about 21. The numerical simulations of the flowfield are able to capture the flows filled in the diffuser and the shock system is fully established in the duct.

Toroidal vs cylindrical analytical description of the magnetic field outside the elongated evolving plasma in tokamaks

In the plasma equilibrium theory, Gajewski's analytical expression [Gajewski, Phys. Fluids 15, 70 (1972)] for the poloidal magnetic flux ψ outside the plasma is known. It was obtained as a solution of the two-dimensional Laplace equation outside an infinite straight cylinder with an elliptical cross section and a uniform current density j ζ. An example of its use for analysis of static configurations is given in the study by Porcelli and Yolbarsop [Phys. Plasmas 26, 054501 (2019)]. Here, we consider the question of its applicability in dynamic problems including, for example, the current quench (CQ) or vertical displacement event (VDE), when the electromagnetic response of the vacuum vessel to the plasma magnetic field evolution has to be accounted for. It is shown that the mentioned cylindrical model does not provide enough information for calculation of the current induced in the wall. Mathematically, this manifests itself in the fact that Gajewski's expression contains an indefinite constant of integration ψ b (hereinafter it is ψ at the plasma boundary), which, in analytical applications, is replaced either by zero or by a value that makes ψ = 0 on the magnetic axis. This does not affect the magnitude of the magnetic field B, but it would incorrectly give the electric field at ∂ B / ∂ t ≠ 0. To eliminate this shortcoming, an additional block of calculations in the toroidal geometry is needed. Here, the problem is solved analytically. The resulting final expression with ψ b well-defined in the toroidal configuration also includes the effects of the Shafranov's shift and inhomogeneity of j ζ. The proposed extensions allow generalization of the earlier results to a wider area and cover such events as CQ or VDE.

The novelty of using the AGM and FEM for solutions of partial differential and ordinary equations along a stretchable straight cylinder

Near the suction/injection area, a scientific definition for laminar boundary layer flow and heat transfer of an incompressible viscous flow over a stretching cylinder is given. In the study, differential equations with partial derivatives are converted into dimensionless coupled equations using numerical and analytical methods of Akbari- Ganji and Finite Elements Methods. The goal of this first stage of research and research on this topic is to use simplified forms to simplify equations using derivatives of simplified forms; the analysis of the displacement of the heat flux and the velocity gradient will be done using the changes of the Prandtl number. Based on the results obtained on this issue, it is found that the suction process increments surface firmness and quality, whereas the injection decreases surface skin friction. Also, at the points where the water and oil are attached to the surface of the cylinder, the heat has reached its maximum value, and as the distance increases along the Y axis, the temperature decreases. The highest temperature gradient is observed for water fluid. This shows that the use of water fluid around the cylinder accelerates the process of heat transfer from the surface to the outside of the boundary layer. One of the differences between the use of oil and water fluid around the cylinder according to the 2D contours is the difference in the temperature gradient of the two fluids. So that the highest temperature gradient is observed for water fluid.

Static Experimental Study on New Arc Multi-Tendon CFRP Cable Anchorage System

CFRP has the potential to replace steel cables in large-span cable-stayed bridges due to its high strength and lightweight material properties. However, the weak lateral force performance of CFRP material creates the challenge of anchoring. This study introduces a new inner cone + arc + straight cylinder bond-type anchorage system to optimize CFRP tendons’ force state. Experimental and finite element analyses verified the new anchoring system’s performance. In static load tensile tests, six groups of seven CFRP tendon anchorage systems with different sleeve grooves were used to study the failure mode and load–strain variation law. The difference in mechanical properties between the new and traditional anchorage is evaluated in the finite element analysis. The results indicate that the new anchorage system can lower the stress concentration in the anchorage zone and enhance anchorage performance. The groove design of the sleeve can effectively increase the anchoring efficiency, where the groove depth is proportional to the anchoring efficiency and the groove spacing is inversely proportional to the anchoring efficiency. The magnitude of the stress inhomogeneity in the multi-tendon anchoring system during tensioning is proportional to the beginning conditions and the load size. When the inner wall of the sleeve becomes more abrasive, the force heterogeneity of the anchorage system reduces. The tests and finite element analysis show that the new anchoring may improve stress distribution and anchorage efficiency. In engineering practice, it can be utilized as a dependable anchorage system.

Increasing reliability of axially compressed cylinders through stiffness tailoring and optimization.

The capabilities of the rapid tow shearing (RTS) process are explored to reduce the well-known imperfection sensitivity of axially compressed cylindrical shells. RTS deposits curvilinear carbon fibre tapes with a fibre-angle-thickness coupling that enables the in situ manufacturing of embedded rings and stringers. By blending the material's elastic modulus and wall thickness smoothly across the cylindrical surface, the load paths can be redistributed favourably with a minimal-design approach that contains part count and weight while ameliorating imperfection sensitivity. A genetic algorithm that incorporates realistic manufacturing imperfections and axial stiffness penalty is used to maximize the 99.9% reliability load of straight fibre (SF) and RTS cylinders. The axial stiffness penalty ensures that reliability does not come at the expense of stiffness. The first-order second-moment method is used to calculate statistical moments that enable an estimate of the 99.9% reliability load. Due to the fibre-angle-thickness coupling of RTS, buckling data are normalized by mass and thickness. Compared to a quasi-isotropic laminate, which corresponds to the optimal eight-layer design for a perfect cylinder, the optimized SF and RTS laminates have a 6% and 8% greater 99.9% normalized reliability load. By relaxing the axial stiffness penalty, the performance benefit can be increased such that SF and RTS cylinders exceed the 99.9% normalized reliability load of an eight-layer quasi-isotropic laminate by 23% and 37%, respectively. Both improvements (with and without penalty functions) stem largely from a reduction in the variance of the buckling-load distribution, thereby demonstrating the potential of fibre-steered cylinders in reducing the imperfection sensitivity of cylindrical shells. This article is part of the theme issue 'Probing and dynamics of shock sensitive shells'.

Effect of respiratory filter on pulmonary function in occupational health examination

Objective: To explore the influence and significance of respiratory filter on the judgment of pulmonary function and the conclusion of occupational health examination in occupational health examination. Methods: From August to November 2020, 252 occupational health examinees were randomly selected as the research objects, and the lung function was examined with the respiratory filter bite and the straight cylinder bite without filter, respectively. The lung function examination indexes and the qualification rate of lung function examination were analyzed and compared between the two groups, and the diagnostic criteria of lung function examination was corrected. Results: 252 subjects were 36 (30, 42) years old. The qualified rate of lung function examination with respiratory filter bite (28.17%, 71/252) was lower than that with straight cylinder bite (34.92%, 88/252) , the difference was statistically significant (P<0.05) . The percentage of forced vital capacity in normal predicted value (FVC%) , percentage of forced expiratory volume in the first second in normal predicted value (FEV(1)%) , and percentage of forced expiratory volume in the first second in forced vital capacity (FEV(1)/FVC%) of subjects using respiratory filter bite were lower than those using the straight cylinder bite (P<0.05) . The corrected diagnostic criteria of pulmonary function were FVC%>78%, FEV(1)%>77%, FEV(1)/FVC%>68%. There was no significant difference between the qualified rate of the respiratory filter bite lung function test calculated according to the corrected diagnostic criteria (35.71%, 90/252) and the qualified rate of the straight cylinder bite lung function test calculated according to the original diagnostic criteria (34.92%, 88/252) (P>0.05) . Conclusion: In occupational health examination, the use of respiratory filter may affect the results of pulmonary function examination. The diagnostic criteria of pulmonary function can be corrected according to different filtering effects to ensure the accuracy of the conclusions of occupational health examination.

End boundary effects on wakes dynamics of inclined circular cylinders

We perform direct numerical simulations to characterize the three-dimensional wake dynamics of long inclined circular cylinders with inhomogeneous end boundary conditions. Three Reynolds numbers, Re=100, 200 and 300, corresponding to the regimes of laminar flow, mode A* wake, and mode B wake, respectively, are considered to reveal the roles of the intrinsic secondary instabilities and the extrinsic end boundary effects in shaping the three-dimensional flows. At Re=100, the end boundary effects are felt over the entire cylinder span by inducing oblique vortex shedding, which is associated with stronger spanwise flow in the wake than a parallel shedding. The Strouhal number of the oblique shedding is related to that of the parallel shedding of straight cylinder by the cosine law, considering the combined inclination angle and oblique angle. At Re=200, the intrinsic secondary instability results in large-scale vortex dislocation, precluding the propagation of the end boundary effects towards further span. Nevertheless, for the inclined cases, oblique shedding is still observed within limited span from the upstream end boundary. The oblique vortices feature intact and straight vortex cores, and are related to the two-dimensional flow at Re=200 (that are void of vortex dislocations) from the viewpoint of cosine law. Further along the span, the oblique vortices destabilizes with the formation of small-scale vortices, and the flow transitions to the typical mode A* wake. At Re=300, the highly three-dimensional flow near the end boundary creates disturbances that travel along the cylinder span, creating vortex dislocations for cases with low inclination angles. For high inclination angle, oblique vortex shedding is again observed over the cylinder span, and is not disrupted by vortex dislocations of either intrinsic or extrinsic causes. The present study offers renewed insights into the three-dimensional wake dynamics of inclined cylinders, and lays the foundation for the designs of long flexible engineering structures and related flow control techniques.