Publications related to Process simulation

Water management of the proton exchange membrane fuel cells: Optimizing the effect of microstructural properties on the gas diffusion layer liquid removal

The formation of water columns inside the gas diffusion layer (GDL) of the proton exchange membrane fuel cell (PEMFC), which is harmful phenomenon, can be controlled by the GDL's microstructure and material. Using computational fluid dynamics (CFD), a thre ...

PERGAMON-ELSEVIER SCIENCE LTD2022

Increasing Superstructure Optimization Capacity Through Self-Learning Surrogate Models

François Maréchal, Ivan Daniel Kantor, Julia Granacher

Simulation-based optimization models are widely applied to find optimal operating conditions of processes. Often, computational challenges arise from model complexity, making the generation of reliable design solutions difficult. We propose an algorithm fo ...

2021

A solution method for predictive simulations in a stochastic environment

Anne Daniëlle Koelewijn

Predictive gait simulations currently do not account for environmental or internal noise. We describe a method to solve predictive simulations of human movements in a stochastic environment using a collocation method. The optimization is performed over mul ...

2020

Robust Monte-Carlo Simulations in Diffusion-MRI: Effect of the Substrate Complexity and Parameter Choice on the Reproducibility of Results

Jean-Philippe Thiran, Gabriel Girard, Erick Jorge Canales Rodriguez, David Paul Roger Romascano, Jonathan Rafael Patino Lopez, Alonso Ramirez Manzanares

Monte-Carlo Diffusion Simulations (MCDS) have been used extensively as a ground truth tool for the validation of microstructure models for Diffusion-Weighted MRI. However, methodological pitfalls in the design of the biomimicking geometrical configurations ...

2020

Electromagnetic Time Reversal Similarity Characteristics and its Application to Locating Faults in Power Networks

Mario Paolone, Farhad Rachidi-Haeri, Zhaoyang Wang, Reza Razzaghi

The existing Electromagnetic Time Reversal (EMTR)-based fault location methods generally leverage the features of the signals simulated in the EMTR reversed-time stage (relative to the direct-time stage wherein a fault occurs and its originated transient s ...

2020

Bioethanol production from palm wood using Trichoderma reesei and Kluveromyces marxianus

Edgard Gnansounou

In the present work, palm wood was pretreated using hydrothermal technique in conjunction with chemical method for removal of lignin. Pretreated palm wood was subjected to hydrolysis using Trichoderma reesei MTCC 4876. Subsequently bioethanol was produced ...

Elsevier2019

Optimal Load Sharing for Serial Compressors via Modifier Adaptation

Dominique Bonvin, Timm Faulwasser, René Uwe Schneider, Predrag Milosavljevic

This paper investigates the optimal load-sharing problem of serial gas compressors in the presence of plant-model mismatch. The problem is formulated as a static real-time optimization task that is solved via modifier adaptation for interconnected systems. ...

IEEE2018

Stable Simulation of Multiport Passive Distributed Networks Using Time Marching Method

Farhad Rachidi-Haeri, Akiyoshi Tatematsu

In this paper, we present a stable method for simulating passive distributed networks connected to linear and nonlinear devices using the time marching (TM) method. The method is based on the use of the Z-transform for analyzing and obtaining the TM equati ...

Institute of Electrical and Electronics Engineers2017

Identification of a Predator-Prey System from Simulation Data of a Convection Model

Jan Sickmann Hesthaven

The use of low-dimensional dynamical systems as reduced models for plasma dynamics is useful as solving an initial value problem requires much less computational resources than fluid simulations. We utilize a data-driven modeling approach to identify a red ...

American Institute of Physics2017

Stable Simulation of Nonlinearly Loaded Lossy Transmission Lines with Time Marching Approach

Farhad Rachidi-Haeri, Akiyoshi Tatematsu

A stable method for the analysis of lossy transmission lines with nonlinear loads is presented. The simulation employs the time marching (TM) method for solving the convolution equations in the time domain. To cope with the late-time instability of the TM ...

Ieee2016

Predictive Models for Thermal Stability and Explosive Properties of Chemicals from Molecular Structure

Nadia Baati

Industrial chemical processes may involve thermal risks as most of the reactions performed are exothermic, the chemicals used are often thermally unstable, and the operating conditions are set to induce high conversion and throughput. Besides the reactive ...

EPFL2016

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

François Avellan, Ebrahim Jahanbakhsh, Christian Vessaz

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

Integrating Rate Based Models into a Multi-Objective Process Design & Optimisation Framework using Surrogate Models

Levent Sinan Teske

In the development of energy and chemical processes, the process engineers extensively apply computer aided methods to design & optimise these processes and corresponding process units. Such applications are multi-scale modelling and multi-objective optimi ...

EPFL2014

Integrating rate based models into multi-objective optimisation of process designs using surrogate models

François Maréchal, Levent Sinan Teske

Multi-objective optimisation (MOO) of super-structured process designs are expensive in CPU- time because of the high number of potential configurations and operation conditions to be calculated. Thus single process units are generally represented by simpl ...

2013

A simulation-based optimization framework for urban transportation problems

Michel Bierlaire, Carolina Osorio Pizano

This paper proposes a simulation-based optimization (SO) method that enables the efficient use of complex stochastic urban traffic simulators to address various transportation problems. It presents a metamodel that integrates information from a simulator w ...

Informs2013

Modelling Hydration Kinetics of Cementitous Systems

Aditya Kumar

The modeling platform µic has been extended to study the hydration of cement based systems. It is shown that the hydration kinetics of alite can be described through the implementation of two mechanisms: a solution controlled dissolution (SCD) mechanism fo ...

EPFL2012

Quantum dynamics study of the competing ultrafast intersystem crossing and internal conversion in the "channel 3" region of benzene

Thomas James Penfold

Time-resolved photoelectron spectroscopy can obtain detailed information about the dynamics of a chemical process on the femtosecond timescale. The resulting signal from such detailed experiments is often difficult to analyze and therefore theoretical calc ...

American Institute of Physics2012

Base case process development for energy efficiency improvement, application to a Kraft pulping mill. Part II: Benchmarking analysis

François Maréchal

A new procedure for benchmarking analysis has been developed to evaluate the energy efficiency of a chemical process. Benchmarking is performed to identify process inefficiencies before developing energy enhancement measures. The new procedure combines typ ...

2011

Hydrogen-Assisted Transformation of CO2 on Nickel: The Role of Formate and Carbon Monoxide

Alfonso Baldereschi, Michele Rizzi

The nanoscale description of the reaction pathways and of the role of the intermediate species involved in a chemical process is a crucial milestone for tailoring more active, stable, and cheaper catalysts, thus providing "reaction engineering" capabilitie ...

2010

Numerical modeling of laminar annular film condensation for different channel shapes

John Richard Thome, Stefano Nebuloni

This paper presents a theoretical and numerical model to predict film condensation heat transfer in mini and micro-channels of different internal shapes. The model is based on a finite volume formulation of the Navier-Stokes and energy equations and it inc ...

Elsevier2010