Publications de Ebrahim Jahanbakhsh

GPU-accelerated numerical analysis of jet interference in a six-jet Pelton turbine using Finite Volume Particle Method

François Avellan, Christian Vessaz, Ebrahim Jahanbakhsh, Sebastián Camilo Leguizamón Sarmiento, Siamak Alimirzazadeh, Audrey Paulette Solange Maertens, Takashi Kumashiro

The Pelton turbine is an impulse turbine typically installed for high head hydroelectric power plants. For a site with a rated head H and discharge Q, a higher specific speed turbine results in a more compact generating unit with reduced manufacturing cost ...

Pergamon-Elsevier Science Ltd2020

Multiscale simulation of erosive wear in a prototype-scale Pelton runner

François Avellan, Ebrahim Jahanbakhsh, Sebastián Camilo Leguizamón Sarmiento, Siamak Alimirzazadeh

The technical capacity to predict the erosion process is instrumental for the optimization of the runner designs and operation strategies of hydroelectric plants. A multiscale model of erosion recently formulated by the authors and validated on a laborator ...

Pergamon-Elsevier Science Ltd2020

GPU-accelerated Pelton turbine simulation using finite volume particle method coupled with linear eddy viscosity models

François Avellan, Ebrahim Jahanbakhsh, Sebastián Camilo Leguizamón Sarmiento, Siamak Alimirzazadeh, Audrey Paulette Solange Maertens, Takashi Kumashiro

The numerical investigation of the unsteady flow patterns around a Pelton bucket can be helpful to improve the overall turbine efficiency by optimizing the bucket design based on identified loss mechanisms. Since the flow is highly turbulent, modeling the ...

IOP PUBLISHING LTD2019

Simulation of the hydroabrasive erosion of a bucket: A multiscale model with projective integration to circumvent the spatio-temporal scale separation

François Avellan, Ebrahim Jahanbakhsh, Sebastián Camilo Leguizamón Sarmiento, Siamak Alimirzazadeh, Audrey Paulette Solange Maertens

The hydroabrasive erosion of hydraulic machine components, especially Pelton buckets and needles, is a widespread problem that entails significant costs. The multiscale nature of the process renders its simulation very computationally demanding unless spec ...

IOP PUBLISHING LTD2019

FVPM numerical simulation of the effect of particle shape and elasticity on impact erosion

François Avellan, Ebrahim Jahanbakhsh, Sebastián Camilo Leguizamón Sarmiento, Siamak Alimirzazadeh, Audrey Paulette Solange Maertens

The erosion of hydraulic machines by solid particle impacts is a widespread problem that leads to outage for expensive repairs, efficiency reduction, and cavitation enhancement. Numerical simulations can be used to study the phenomenon, provided they featu ...

ELSEVIER SCIENCE SA2019

Multiscale Simulation of the Hydroabrasive Erosion of a Pelton Bucket: Bridging Scales to Improve the Accuracy

François Avellan, Ebrahim Jahanbakhsh, Sebastián Camilo Leguizamón Sarmiento, Siamak Alimirzazadeh, Audrey Paulette Solange Maertens

Erosive wear of hydraulic machines is a common issue, which results in efficiency degradation, the enhancement of cavitation, and the need for expensive maintenance. Although numerical simulations of the erosion process could be very useful, both for under ...

2019

Numerical investigation of the jet velocity profile and its influence on the Pelton turbine performance

François Avellan, Ebrahim Jahanbakhsh, Sebastián Camilo Leguizamón Sarmiento, Siamak Alimirzazadeh, Audrey Paulette Solange Maertens, Takashi Kumashiro

Numerical investigation of the unsteady flow patterns around the bucket can be helpful to improve the Pelton turbine efficiency. In fact, by studying the loss mechanisms in the flow, one can optimize the bucket design. For this purpose, an accurate investi ...

IOP PUBLISHING LTD2019

GPU-Accelerated 3-D Finite Volume Particle Method

François Avellan, Ebrahim Jahanbakhsh, Sebastián Camilo Leguizamón Sarmiento, Siamak Alimirzazadeh, Audrey Paulette Solange Maertens

2018

A novel approach to surface tension modelling with the Finite Volume Particle Method

François Avellan, Ebrahim Jahanbakhsh, Audrey Paulette Solange Maertens

2018

Exact finite volume particle method with spherical-support kernels

François Avellan, Christian Vessaz, Ebrahim Jahanbakhsh, Audrey Paulette Solange Maertens

The Finite Volume Particle Method (FVPM) is a meshless method for simulating fluid flows which includes many of the desirable features of mesh-based finite volume methods. In this paper, we develop a new 3-D FVPM formulation that features spherical kernel ...

Elsevier2017

A multiscale model for the simulation of sediment impact erosion of metallic targets using the finite volume particle method

François Avellan, Ebrahim Jahanbakhsh, Sebastián Camilo Leguizamón Sarmiento, Siamak Alimirzazadeh, Audrey Paulette Solange Maertens

2017

A GPU-accelerated versatile solver based on the finite volume particle method

François Avellan, Ebrahim Jahanbakhsh, Sebastián Camilo Leguizamón Sarmiento, Siamak Alimirzazadeh, Audrey Paulette Solange Maertens

2017

A multiscale model for sediment impact erosion simulation using the finite volume particle method

François Avellan, Ebrahim Jahanbakhsh, Sebastián Camilo Leguizamón Sarmiento, Siamak Alimirzazadeh, Audrey Paulette Solange Maertens

The erosion of a surface by a sediment-laden flow is an inherently multiscale phenomenon which includes physical interactions covering many orders of magnitude in both length and time scales. Conforming to the nature of the problem, we propose a novel mult ...

2017

A spherical kernel for the Finite Volume Particle Method and application to surface tension

François Avellan, Ebrahim Jahanbakhsh, Audrey Paulette Solange Maertens

2016

Development of a finite volume particle method for 3-D fluid flow simulations

François Avellan, Christian Vessaz, Ebrahim Jahanbakhsh, Audrey Paulette Solange Maertens

The Finite Volume Particle Method (FVPM) is a meshless method for simulating fluid flows which includes many of the desirable features of mesh-based finite volume methods. FVPM benefits from particle interaction vectors to weight conservative fluxes exchan ...

Elsevier2016

Impact erosion prediction using the finite volume particle method with improved constitutive models

François Avellan, Christian Vessaz, Ebrahim Jahanbakhsh, Sebastián Camilo Leguizamón Sarmiento, Siamak Alimirzazadeh, Audrey Paulette Solange Maertens

Erosion damage in hydraulic turbines is a common problem caused by the high- velocity impact of small particles entrained in the fluid. In this investigation, the Finite Volume Particle Method is used to simulate the three-dimensional impact of rigid spher ...

IOP Publishing Ltd2016

Flow Simulation of Jet Deviation by Rotating Pelton Buckets Using Finite Volume Particle Method

François Avellan, Christian Vessaz, Ebrahim Jahanbakhsh

The objective of the present paper is to perform numerical simulations of a high-speed water jet impinging on rotating Pelton buckets using the finite volume particle method (FVPM), which combines attractive features of smoothed particle hydrodynamics (SPH ...

2015

Finite Volume Particle Method for Fluid-Structure Interaction

François Avellan, Christian Vessaz, Ebrahim Jahanbakhsh, Audrey Paulette Solange Maertens

We have recently developed a conservative ﬁnite volume particle method (FVPM) that can efﬁciently model 2-D and 3-D ﬂuid ﬂow with free-surfaces and complex geometries. Tn this paper we present an extension of the method to ﬂuid-structure interaction. A new ...

2015

Simulation of Silt Erosion Using Particle-Based Methods

Ebrahim Jahanbakhsh

Increasing demand for clean sources of energy have forced electricity providers to paymore attention to their hydropower assets. Silt erosion is a destructive phenomenon that may occur in hydropower plants. The power plant subjected to silt erosion require ...

EPFL2014

Silt motion simulation using finite volume particle method

François Avellan, Christian Vessaz, Ebrahim Jahanbakhsh

In this paper, we present a 3-D FVPM which features rectangular top-hat kernels. With this method, interaction vectors are computed exactly and efficiently. We introduce a new method to enforce the no-slip boundary condition. With this boundary enforcement ...

IOP Publishing Ltd2014