Topic
Streamlines, streaklines, and pathlines
About: Streamlines, streaklines, and pathlines is a research topic. Over the lifetime, 6118 publications have been published within this topic receiving 133556 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: In this paper , the authors describe a system for visualizing convection in the Earth's mantle using hybrid rendering, a combination of interactive raytracing, raycasting, and conventional rasterization graphics.
Abstract: In this article, we describe our system for visualizing convection in the Earth’s mantle using hybrid rendering—a combination of interactive raytracing, raycasting, and conventional rasterization graphics. The dataset for the SciVis 2021 contest includes a velocity vector field and multiple scalar fields, such as temperature and thermal conductivity anomalies, which we display using isosurface raycasting, streamlines, and line integral convolution, among other techniques. We demonstrate how these methods can be used to explore the dataset, identify slabs, plumes, and stagnations, and detect the influence of 660-km depth endothermic phase transition and mid-mantle spin transition on the mantle dynamics.
03 Jan 2023
TL;DR: In this paper , the setting angle of the inlet guide vane (IGV) was investigated to reduce the effect of pre-swirl intensity on axial-flow performance.
Abstract: Abstract Inlet flow direction significantly affects the hydraulic performance of an axial-flow pump. Usually, the research papers ignore this phenomenon, resulting in discrepancies between simulation and experimental results. This study examines the influence of inflow direction in five cases (0%, 5%, 10%, 15%, and 30% pre-swirl intensities) to determine the relationship between the pre-swirl intensity and the hydraulic performance of the axial-flow pump. Based on this, changing the setting angle of the inlet guide vane (IGV) is proposed and thoroughly investigated to reduce the effect of inflow direction. In this study, the influence of clearances in IGV blades on hydraulic performance is also investigated in detail. Numerical simulations are performed using ANSYS–CFX and a shear stress transport reattachment modification (SST k-) turbulence model with small y+ values at all walls. Specifically, the hydraulic performance curves and internal flow characteristics, including contours and streamlines, are assessed and analyzed. The inflow direction significantly impacts the hydraulic efficiency of the axial-flow pump. Increased pre-swirl intensity causes more loss in the IGV passage. The internal flow field and performance are not affected by the clearance at the hub and shroud of the IGV. However, the tip clearance of the impeller causes a decrease in hydraulic efficiency due to the tip leakage vortex. By adjusting the setting angle of the IGV, the efficiency and head gradually increase from a negative to a positive setting angle. Additionally, 30° is considered the critical setting angle for IGV.
TL;DR: In this article , the mixed convection of Fe3O4-water magnetic nanofluid in a heated porous open cavity was studied using the two-phase model, where the Brownian and thermophoresis of nanoparticles in the carrier fluid were considered.
Abstract: The aim of the current work is to study the mixed convection of Fe3O4-water magnetic nanofluid in a heated porous open cavity. Buongiorno's two-phase model is utilised to consider the Brownian and thermophoresis of nanoparticles in the carrier fluid. Using the Darcy-Brinkman and Boussinesq approximations, the governing equations are solved by the finite volume technique, numerically. Numerical computations are performed for various Richardson numbers (Ri = 0.01, 0.1, 1 and 10), Reynolds numbers (Re = 10, 100, 300 and 600), volume fraction of nanoparticle (φ = 0 and 0.06), porosity (ε = 0.5, 0.8 and 1) and Darcy numbers (0.0002 ≤ Da ≤ 500,000). The nanofluid flow and heat transfer rate are discussed in detail by contour plots of streamlines and isotherms of nanoparticles. Numerical results indicate that increasing Reynolds number increases the average Nusselt number. However, in low Darcy numbers, porosity has no significant effect on the Nusselt number.
02 May 2023
TL;DR: In this paper , the characteristics of Taylor cells in an elliptical outer cylinder with a rotating concentric inner circular cylinder were studied and a pressure-projection algorithm was used to advance the flow equations in time.
Abstract: Taylor-Couette flow between rotating cylinders is a classical problem in fluid mechanics and has been extensively studied in the case of two concentric circular cylinders. There have been relatively small number of studies in complex-shaped cylinders with one or both cylinders rotating. In this paper, we study the characteristics of Taylor cells in an elliptical outer cylinder with a rotating concentric inner circular cylinder. We numerically solve the three-dimensional unsteady Navier-Stokes equations assuming periodicity in the axial direction. We use a Fourier-spectral meshless discretization by interpolating variables at scattered points using polyharmonic splines and appended polynomials. A pressure-projection algorithm is used to advance the flow equations in time. Results are presented for an ellipse of aspect ratio two and for several flow Reynolds numbers ($Re = \omega r_i (b-r_i))/
u$, where $\omega$ = angular velocity [rad/s], $r_i$ = radius of inner cylinder, $b$ = semi-minor axis, and $
u$ = kinematic viscosity) from subcritical to 300. Streamlines, contours of axial velocity, pressure, vorticity, and temperature are presented along with surfaces of Q criterion. The flow is observed to be steady until $Re = 300$ and unsteady at $Re = 350$.