Numerical Modeling of an Aero-Engine Bearing Chamber Using the Meshless Smoothed Particle Hydrodynamics Method

2015 ◽  
Author(s):  
Lars Wieth ◽  
Christian Lieber ◽  
Wolfram Kurz ◽  
Samuel Braun ◽  
Rainer Koch ◽  
...  
Keyword(s):  
Boundary Conditions ◽  
Numerical Method ◽  
Smoothed Particle Hydrodynamics ◽  
Gas Turbines ◽  
Flow Regimes ◽  
Sph Method ◽  
Aero Engine ◽  
Particle Hydrodynamics ◽  
Smoothed Particle ◽  
Engine Bearing

The prediction of the two-phase flow in an aero-engine bearing chamber using the meshless Lagrangian Smoothed Particle Hydrodynamics (SPH) method is presented in this paper. The prediction of the prevailing flow types, like shear-driven wallfilms, droplet-wall- and droplet-film-interactions require an accurate numerical method, which is robust and efficient. Therefore, a code based on the SPH method was developed and validated to numerically predict such technical relevant multi-phase flows in gas turbines. The simulations to be presented in this paper are focused on an aero-engine bearing chamber configuration, which was experimentally investigated previously. For time saving reasons, the bearing chamber is modeled as two-dimensional problem. This requires special boundary conditions for the oil- and sealing-air flow inlet and outlet, which must physically reflect those of the experiments. In the experiments different operating regimes at different boundary conditions could be identified. The major objective of the simulations is to investigate if those different flow regimes can be captured by the numerical method. The simulations do reproduce the different flow regimes highly accurate and demonstrate the ability of this new approach.

Modeling Fuel Injection in Gas Turbines Using the Meshless Smoothed Particle Hydrodynamics Method

2013 ◽  
Author(s):  
S. Braun ◽  
C. Höfler ◽  
R. Koch ◽  
H.-J. Bauer
Keyword(s):  
Smoothed Particle Hydrodynamics ◽  
Gas Turbines ◽  
Fuel Injection ◽  
Numerical Code ◽  
Test Cases ◽  
Jet Engines ◽  
Sph Method ◽  
Particle Hydrodynamics ◽  
Smoothed Particle ◽  
Extensive Experimental Data

For predicting primary atomization a numerical code has been developed based on the Lagrangian Smoothed Particle Hydrodynamics (SPH) method. The advantage of this approach is the inherent interface advection. In contrast to commonly used grid based methods such as the Volume of Fluid (VoF) or Level Set method there is no need for costly and approximative interface tracking or reconstruction techniques which are required to avoid interface diffusion. It has been demonstrated by various test cases that the SPH method is capable to correctly predict single — as well as multiphase flows including the effect of surface tension. The goal of this work is to further develop the methodology with the intention to simulate primary atomization within airblast atomizers of jet engines. The authors present two test cases relevant for the simulation of primary atomization. The shear-driven deformation of a fuel droplet in a gaseous flow has been investigated and compared to data from literature. Moreover, the liquid film disintegration at the trailing edge of a planar prefilming airblast atomizer has been studied. The geometry has been derived from an existing test rig, where extensive experimental data have been acquired. Resulting droplet sizes and shear-off frequencies for different geometrical setups have been analyzed and compared to the experiment. The results reveal the promising performance of this new method for predicting primary atomization.

Using an SPH-Based Continuum Representation of Granular Terrain to Simulate the Rover Mobility

2021 ◽  
Author(s):  
Wei Hu ◽  
Jason Zhou ◽  
Radu Serban ◽  
Dan Negrut
Keyword(s):  
Boundary Conditions ◽  
Granular Material ◽  
Smoothed Particle Hydrodynamics ◽  
Continuum Model ◽  
Sph Method ◽  
Particle Hydrodynamics ◽  
Smoothed Particle ◽  
Speed Up

Abstract We use the Smoothed Particle Hydrodynamics (SPH) method to determine the dynamics of granular material in its interaction with a four-wheel rover. The goal of the simulation is to investigate the mobility of the rover while operating on granular terrains. In order to speed up the simulation, we employ a continuum model to capture the dynamics of the deformable terrain. The rover wheel geometry is defined through a mesh. The granular material is modeled as an elasto-plastic continuum that dynamically interacts with the rigid wheels of the rover in a Chrono [1] co-simulation setup. The interaction between each wheel and the granular terrain is handled through so-called Boundary Conditions Enforcing (BCE) particles which are attached to the rover wheel. Several simulations are performed to assess the rover robustness for operation in flat (with obstacles), uphill, downhill, and side-tilted mobility scenarios.

scholarly journals An Application of the Cahn-Hilliard Approach to Smoothed Particle Hydrodynamics

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
M. Hirschler ◽  
M. Huber ◽  
W. Säckel ◽  
P. Kunz ◽  
U. Nieken
Keyword(s):  
Phase Separation ◽  
Boundary Conditions ◽  
Smoothed Particle Hydrodynamics ◽  
Sph Method ◽  
Free Surfaces ◽  
Diffusion Controlled ◽  
Universal Power Law ◽  
Particle Hydrodynamics ◽  
Smoothed Particle ◽  
Solid Walls

The development of a methodology for the simulation of structure forming processes is highly desirable. The smoothed particle hydrodynamics (SPH) approach provides a respective framework for modeling the self-structuring of complex geometries. In this paper, we describe a diffusion-controlled phase separation process based on the Cahn-Hilliard approach using the SPH method. As a novelty for SPH method, we derive an approximation for a fourth-order derivative and validate it. Since boundary conditions strongly affect the solution of the phase separation model, we apply boundary conditions at free surfaces and solid walls. The results are in good agreement with the universal power law of coarsening and physical theory. It is possible to combine the presented model with existing SPH models.

scholarly journals Numerical Simulation of Non-Homogeneous Viscous Debris-Flows Based on the Smoothed Particle Hydrodynamics (SPH) Method

Water ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 2314 ◽  
Author(s):  
Shu Wang ◽  
Anping Shu ◽  
Matteo Rubinato ◽  
Mengyao Wang ◽  
Jiping Qin
Keyword(s):  
Debris Flow ◽  
Water Content ◽  
Smoothed Particle Hydrodynamics ◽  
Debris Flows ◽  
Sph Method ◽  
Particle Hydrodynamics ◽  
Sph Model ◽  
Smoothed Particle ◽  
The Impact ◽  
Kinetic And Potential Energies

Non-homogeneous viscous debris flows are characterized by high density, impact force and destructiveness, and the complexity of the materials they are made of. This has always made these flows challenging to simulate numerically, and to reproduce experimentally debris flow processes. In this study, the formation-movement process of non-homogeneous debris flow under three different soil configurations was simulated numerically by modifying the formulation of collision, friction, and yield stresses for the existing Smoothed Particle Hydrodynamics (SPH) method. The results obtained by applying this modification to the SPH model clearly demonstrated that the configuration where fine and coarse particles are fully mixed, with no specific layering, produces more fluctuations and instability of the debris flow. The kinetic and potential energies of the fluctuating particles calculated for each scenario have been shown to be affected by the water content by focusing on small local areas. Therefore, this study provides a better understanding and new insights regarding intermittent debris flows, and explains the impact of the water content on their formation and movement processes.

scholarly journals Progress in the Smoothed Particle Hydrodynamics Method to Simulate and Post-process Numerical Simulations of Annular Airblast Atomizers

2020 ◽  
Vol 105 (4) ◽  
pp. 1119-1147
Author(s):  
G. Chaussonnet ◽  
T. Dauch ◽  
M. Keller ◽  
M. Okraschevski ◽  
C. Ates ◽  
...  
Keyword(s):  
Smoothed Particle Hydrodynamics ◽  
Flux Ratio ◽  
Liquid Sheet ◽  
Sph Method ◽  
Post Process ◽  
Finite Time Lyapunov Exponent ◽  
Fragmentation Spectrum ◽  
Particle Hydrodynamics ◽  
Primary Breakup ◽  
Smoothed Particle

AbstractThis paper illustrates recent progresses in the development of the smoothed particle hydrodynamics (SPH) method to simulate and post-process liquid spray generation. The simulation of a generic annular airblast atomizer is presented, in which a liquid sheet is fragmented by two concentric counter swirling air streams. The accent is put on how the SPH method can bridge the gap between the CAD geometry of a nozzle and its characterization, in terms of spray characteristics and dynamics. In addition, the Lagrangian nature of the SPH method allows to extract additional data to give further insight in the spraying process. First, the sequential breakup events can be tracked from one large liquid blob to very fine stable droplets. This is herein called the tree of fragmentation. From this tree of fragmentation, abstract quantities can be drawn such as the breakup activity and the fragmentation spectrum. Second, the Lagrangian coherent structures in the turbulent flow can be determined easily with the finite-time Lyapunov exponent (FTLE). The extraction of the FTLE is particularly feasible in the SPH framework. Finally, it is pointed out that there is no universal and ultimate non-dimensional number that can characterize airblast primary breakup. Depending on the field of interest, a non-dimensional number (e.g. Weber number) might be more appropriate than another one (e.g. momentum flux ratio) to characterize the regime, and vice versa.

scholarly journals Application of Smoothed Particle Hydrodynamics (SPH) for the Simulation of Flow-like Landslides on 3D Terrains

2022 ◽  
Author(s):  
Binghui Cui ◽  
Liaojun Zhang
Keyword(s):  
Risk Assessment ◽  
Smoothed Particle Hydrodynamics ◽  
Disaster Mitigation ◽  
Sph Method ◽  
Landslide Event ◽  
Particle Hydrodynamics ◽  
Smoothed Particle ◽  
Simulation Results ◽  
Mitigation Design ◽  
The Impact

Abstract Flow-type landslide is one type of landslide that generally exhibits characteristics of high flow velocities, long jump distances, and poor predictability. Simulation of it facilitates propagation analysis and provides solutions for risk assessment and mitigation design. The smoothed particle hydrodynamics (SPH) method has been successfully applied to the simulation of two-dimensional (2D) and three-dimensional (3D) flow-like landslides. However, the influence of boundary resistance on the whole process of landslide failure is rarely discussed. In this study, a boundary algorithm considering the friction is proposed, and integrated into the boundary condition of the SPH method, and its accuracy is verified. Moreover, the Navier-Stokes equation combined with the non-Newtonian fluid rheology model was utilized to solve the dynamic behavior of the flow-like landslide. To verify its performance, the Shuicheng landslide event, which occurred in Guizhou, China, was taken as a case study. In the 2D simulation, a sensitivity analysis was conducted, and the results showed that the shearing strength parameters have more influence on the computation accuracy in comparison with the coefficient of viscosity. Afterwards, the dynamic characteristics of the landslide, such as the velocity and the impact area, were analyzed in the 3D simulation. The simulation results are in good agreement with the field investigations. The simulation results demonstrate that the SPH method performs well in reproducing the landslide process, and facilitates the analysis of landslide characteristics as well as the affected areas, which provides a scientific basis for conducting the risk assessment and disaster mitigation design.

Smoothed Particle Hydrodynamics into the Fluid Dynamics of Classical Problems

2016 ◽  
Vol 846 ◽  
pp. 73-78 ◽  
Author(s):  
Maziar Gholami Korzani ◽  
S. Galindo Torres ◽  
Alexander Scheuermann ◽  
David J. Williams
Keyword(s):  
Fluid Dynamics ◽  
Analytical Solutions ◽  
Poiseuille Flow ◽  
Smoothed Particle Hydrodynamics ◽  
Slip Boundary Condition ◽  
Sph Method ◽  
Slip Boundary ◽  
Particle Hydrodynamics ◽  
Smoothed Particle ◽  
Computational Fluid Dynamics Cfd

The study concerns the application of the Smoothed Particle Hydrodynamics (SPH) method within the computational fluid dynamics (CFD). In the present study, some classical problems – the Poiseuille flow, the Hagen-Poiseuille flow, and the Couette flow – with the analytical solutions were investigated to verify a newly developed code of SPH. The code used for solving these problems, is an entirely parallel SPH solver in 3D and has been developed by the authors. Fluid was modelled as a viscous liquid with weak compressibility. The boundary walls were simulated with a special set of fixed boundary particles, and no-slip boundary condition was considered. Computational results were compared to available analytical solutions for transient hydraulic processes. Good agreement is achieved for the whole transient stage of the considered problems until steady state is reached. The results of this study highlight the potential of SPH to tackle a broad range of problems in fluid mechanics.

A STABLE LARGE DEFORMATION CORRECTED SPH METHOD BASED ON STABILIZED CONFORMING NODAL INTEGRATION AND LAGRANGIAN KERNELS

2012 ◽  
Vol 09 (04) ◽  
pp. 1250057
Author(s):  
S. WANG
Keyword(s):  
Large Deformation ◽  
Smoothed Particle Hydrodynamics ◽  
Solid Mechanics ◽  
Particle Methods ◽  
Sph Method ◽  
Nodal Integration ◽  
Particle Hydrodynamics ◽  
Smoothed Particle ◽  
Meshless Approximation ◽  
Complex Phenomena

In this paper, we propose a Galerkin-based smoothed particle hydrodynamics (SPH) formulation with moving least-squares meshless approximation, applied to solid mechanics and large deformation. Our method is truly meshless and based on Lagrangian kernel formulation and stabilized nodal integration. The performance of the methodology proposed is tested through various simulations, demonstrating the attractive ability of particle methods to handle severe distortions and complex phenomena.

Sign in / Sign up

Export Citation Format

Share Document