scholarly journals Smoothed Particle Hydrodynamics Simulations of Water Flow in a 90° Pipe Bend

Water ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1081
Author(s):  
Leonardo Di G. Sigalotti ◽  
Carlos E. Alvarado-Rodríguez ◽  
Jaime Klapp ◽  
José M. Cela

The flow through pipe bends and elbows occurs in a wide range of applications. While many experimental data are available for such flows in the literature, their numerical simulation is less abundant. Here, we present highly-resolved simulations of laminar and turbulent water flow in a 90° pipe bend using Smoothed Particle Hydrodynamics (SPH) methods coupled to a Large-Eddy Simulation (LES) model for turbulence. Direct comparison with available experimental data is provided in terms of streamwise velocity profiles, turbulence intensity profiles and cross-sectional velocity maps at different stations upstream, inside and downstream of the pipe bend. The numerical results are in good agreement with the experimental data. In particular, maximum root-mean-square deviations from the experimental velocity profiles are always less than ∼1.4%. Convergence to the experimental measurements of the turbulent fluctuations is achieved by quadrupling the resolution necessary to guarantee convergence of the velocity profiles. At such resolution, the deviations from the experimental data are ∼0.8%. In addition, the cross-sectional velocity maps inside and downstream of the bend shows that the experimentally observed details of the secondary flow are also very well predicted by the numerical simulations.

Author(s):  
Carlos Alvarado ◽  
Leonardo Di G. Sigalotti ◽  
Jaime Klapp ◽  
Celia R. Fierro-Santillan ◽  
Fernando Aragon ◽  
...  

Abstract The swirling secondary flow in curved pipes is studied in three-space dimensions using a weakly compressible Smoothed Particle Hydrodynamics (WCSPH) formulation coupled to new non-reflecting outflow boundary conditions. A large eddy simulation (LES) model for turbulence is benchmarked with existing experimental data. After validation of the present model against experimental results for a $90^{\circ}$ pipe bend, a detailed numerical study aimed at reproducing experimental flow measurements for a wide range of Reynolds numbers has been performed for different pipe geometries, including U pipe bends, S-shaped pipes and helically coiled pipes. In all cases, the SPH calculated behavior shows reasonably good agreement with the measurements across and downstream the bend in terms of streamwise velocity profiles and cross-sectional contours. Maximum mean-root- square deviations from the experimentally obtained profiles are always less than $\sim 1.8$\%. This combined with the very good matching between the SPH and the experimental cross-sectional contours shows the uprising capabilities of the present scheme for handling engineering applications with streamline curvature, such as flows in bends and manifolds.


Author(s):  
Abdelraheem M. Aly

Purpose This paper aims to adopt incompressible smoothed particle hydrodynamics (ISPH) method to simulate MHD double-diffusive natural convection in a cavity containing an oscillating pipe and filled with nanofluid. Design/methodology/approach The Lagrangian description of the governing partial differential equations are solved numerically using improved ISPH method. The inner oscillating pipe is divided into two different pipes as an open and a closed pipe. The sidewalls of the cavity are cooled with a lower concentration C_c and the horizontal walls are adiabatic. The inner pipe is heated with higher concentration C_h. The analysis has been conducted for the two different cases of inner oscillating pipes under the effects of wide range of governing parameters. Findings It is found that a suitable oscillating pipe makes a well convective transport inside a cavity. Presence of the oscillating pipe has effects on the heat and mass transfer and fluid intensity inside a cavity. Hartman parameter suppresses the velocity and weakens the maximum values of the stream function. An increase on Hartman, Lewis and solid volume fraction parameters leads to an increase on average Nusselt number on an oscillating pipe and left cavity wall. Average Sherwood number on an oscillating pipe and left cavity wall decreases as Hartman parameter increases. Originality/value The main objective of this work is to study the MHD double-diffusive natural convection of a nanofluid in a square cavity containing an oscillating pipe using improved ISPH method.


2019 ◽  
Vol 213 ◽  
pp. 02030
Author(s):  
Petr Jančík ◽  
Tomáš Hyhlík

This paper presents a solution of a dam break problem in two dimensions obtained with smoothed particle hydrodynamics (SPH) method. The main focus is on pressure evaluation during the impact on the wall. The used numerical method and the way of pressure evaluation are described in detail. The numerical results of the kinematics and dynamics of the flow are compared with experimental data from the literature. The abilities and limitations of the used methods are discussed.


2012 ◽  
Vol 1 (33) ◽  
pp. 74
Author(s):  
Billy L. Edge ◽  
Margery F. Overton ◽  
Robert A. Dalrymple ◽  
Alexis Hérault ◽  
Giuseppe Bilotta ◽  
...  

Smooth Particle Hydrodynamics is a Lagrangian meshless numerical method with substantially improved capabilities in simulation of both fluid dynamics and solid mechanics due to its meshless nature. GPUSPH is an implementation of Smoothed Particle Hydrodynamics (SPH) on Nvidia CUDA-enabled (graphics) cards. In this paper the GPUSPH is applied to runup and overtopping applications and compared with experimental results from Roos and Battjes for a plane slope and Oaks, Edge and Lynett for complex bathymetry representing a complex levee transition. Results for both models show good comparison with experimental data and suggest GPUSPH as a reasonable tool for complex runup and overtopping problems.


2021 ◽  
Vol 9 (3) ◽  
pp. 244 ◽  
Author(s):  
Bonaventura Tagliafierro ◽  
Simone Mancini ◽  
Pablo Ropero-Giralda ◽  
José M. Domínguez ◽  
Alejandro J. C. Crespo ◽  
...  

Computational Fluid Dynamics simulations of planing hulls are generally considered less reliable than simulations of displacement hulls. This is due to the flow complexity around planing hulls, especially in the bow region, where the sprays are formed. The recent and constant increasing of computational capabilities allows simulating planing hull features, with more accurate turbulence models and advanced meshing procedures. However, mesh-based approaches based on the finite volume methods have shown to be limited in capturing all the phenomena around a planing hull. As such, the focus of this study is on evaluating the ability of the Smoothed Particle Hydrodynamics mesh-less method to numerically solve the 3-D flow around a planing hull and simulate more accurately the spray structures, which is a rather challenging task to be performed with mesh-based tools. A novel application of the DualSPHysics code for simulating a planing hull resistance test has been proposed and applied to the parent hull of the Naples warped planing hull Systematic Series. The drag and the running attitudes (heave and dynamic trim angle) are computed for a wide range of Froude’s numbers and discussed concerning experimental values.


Author(s):  
Ravi Challa ◽  
Solomon C. Yim ◽  
V. G. Idichandy ◽  
C. P. Vendhan

A numerical study on the dynamic response of a generic rigid water-landing object (WLO) during water impact is presented in this paper. The effect of this impact is often prominent in the design phase of the re-entry project to determine the maximum force for material strength determination to ensure structural and equipment integrity, human safety and comfort. The predictive capability of the explicit finite-element (FE) arbitrary Lagrangian-Eulerian (ALE) and smoothed particle hydrodynamics (SPH) methods of a state-of-the-art nonlinear dynamic finite-element code for simulation of coupled dynamic fluid structure interaction (FSI) responses of the splashdown event of a WLO were evaluated. The numerical predictions are first validated with experimental data for maximum impact accelerations and then used to supplement experimental drop tests to establish trends over a wide range of conditions including variations in vertical velocity, entry angle, and object weight. The numerical results show that the fully coupled FSI models can capture the water-impact response accurately for all range of drop tests considered, and the impact acceleration varies practically linearly with increase in drop height. In view of the good comparison between the experimental and numerical simulations, both models can readily be employed for parametric studies and for studying the prototype splashdown under more realistic field conditions in the oceans.


Author(s):  
Ravi Challa ◽  
Solomon Yim ◽  
V. G. Idichandy ◽  
C. P. Vendhan

A numerical study on the dynamic response of a generic rigid water-landing object (WLO) during water impact is presented in this paper. The effect of this impact is often prominent in the design phase of the re-entry project, to determine the maximum force it is subjected to, for material strength determination to ensure structural and equipment integrity, human safety and comfort. The predictive capability of the explicit finite-element arbitrary Lagrangian-Eulerian (ALE) and smoothed particle hydrodynamics (SPH) methods of a state-of-the-art nonlinear dynamic finite-element code for simulation of coupled dynamic fluid structure interaction (FSI) responses of the splashdown event of a WLO were evaluated. The numerical predictions are first validated with experimental data for the maximum impact accelerations and then used to supplement experimental drop tests to establish trends over a wide range of conditions including variations in vertical velocity, entry angle and object weight. The results show that the fully coupled FSI models can capture the water-impact response accurately for all range of drop tests considered and the impact accelerations are practically linearly with the increase in the height of the drop. The reliability of the maximum impact accelerations was calibrated with approximate classical von Karman and Wagner closed-form solutions.


Author(s):  
Debashis Basu ◽  
Kaushik Das ◽  
Ron Janetzke ◽  
Steve Green

This paper presents computational results for two-dimensional (2-D) simulations of geophysical flows using the Smoothed Particle Hydrodynamics (SPH) method. The basic equations solved are the incompressible mass conservation and Navier-Stokes equations, and the discretization is carried out using the SPH method. The simulations are carried out for two problems. The first problem involved a 2-D dam-break problem with mud flow. The second problem involved non-Newtonian flow of deformable landslide on a mild slope. In both the simulations, the flow is assumed to be incompressible. In the present study, the mud flow materials are represented as non-Newtonian fluids with a Bingham model. The effects of the rheological formulation are assessed for the predicted mudflow shape. The simulation results are compared with the experimental data available in open literature. The velocity profiles and the free surface shape are in good agreement with the experimental data. To distinguish between the non-Newtonian model simulations and the Newtonian model, the dam-break simulations were also carried out using water and Newtonian models. The simulations reveal several distinctive flow features between the Newtonian and non-Newtonian approaches. The results of the simulations are of engineering interest in mitigation of natural hazards such as debris flows.


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