Improving complex systems via optimization of black-box, simulated models

About me


Picture of Lucas F. Santos

Thanks for stopping by! My name is Lucas Francisco dos Santos. I am a 26-year-old, enthusiastic, young reasearcher, who is trying to contribute to science and technology in the topic of optimization of complex systems. I am most interested in solving optimization problems with black-box, simulated models embedded using surrogate-based approaches. I really believe that this research topic can improve robust and multi-objective engineering decisions aimed to a more sustainable and technological world. If you are looking for a research collaboration, do not hesitate to contact me by clicking on the following button or by email. If you are just browsing, please enjoy the content!

Education

  • PhD in Chemical Engineering, Aug 2019 - Present
    State University of Maringá
    University of Alicante (Double Degree)
  • MSc in Chemical Engineering, Aug 2018 - Aug 2019
    State University of Maringá
  • BSc in Chemical Engineering, Feb 2013 - Jul 2018
    State University of Maringá
    University of California, Santa Barbara (One-year sandwhich period)

Research Interests

  • Simulation optimization
  • Surrogate-based optimization
  • Mathematical programming
  • Chemical process optimization
  • Chemical process synthesis
  • Natural gas liquefaction process

Skills

Programming

Python, MATLAB, GAMS, C++, LaTeX, HTML, CSS

Process Simulation

Aspen HYSYS, DWSIM, XCOS

Languages

Portuguese, English, Spanish

Code


dwsimopt: DWSIM simulation optimization with Python

The dwsimopt is a Python library that automates DWSIM chemical process simulations for optimization. The simulations dlls are embedded in the programming environment so that it can be accessd and modified by the optimization algorithms. Check out the code in the in the github repository or install the dwsimopt package with pip from the PyPI repository under MIT license.

Mathematical Background

Although very efficient to describe in details complex systems that would otherwise have to be simplified or approximated, black-box process simulators lack the symbolic formulation of the process model equations and the analytical derivatives that are useful for optimization, for example [1]. The optimization models that require simulations to calculate the objective function and/or constraints are often referred to as simulation optimization problem [2]. A simplified version of this class of problems can be described as to find an that solves globally the following constrained problem

in which the objective function and constraints are somewhat expensive to calculate, slightly noisy, and black-box functions.


Installation

Install the latest version of dwsimopt via pip:
pip install dwsimopt
or clone and install it from the github repository:
git clone https://github.com/lf-santos/dwsimopt.git
cd dwsimopt
python setup.py install
Make sure you have the open-source chemical process simulator DWSIM v7.0 installed into your machine. Navegate throught the jupyter notebook examples. Use the SimulationOptimization class to embed your DMSWIM simulation into Python. Add degrees of freedom, objective function and constraints from your simulation optimization problem with the py2dwisim python-dwsim data exchange interface. Solve the problem with a suitable optimization solver (surrogate-based optimization or global optimization meta-heuristics recommended).

Projects


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Surrogate-based simulation optimization

Data-driven models replace the expensive-to-evaluate, black-box, simulator-dependent objective and constraints to assist the search of solution to the optimization problem.

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Direct simulation optimization

Meta-heuristics, derivative-free methods, or gradient-based optimization is applied directly to the black-box, simulation optimization problem.

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Work and heat exchange networks (WHENs) synthesis

Superstructure-derived MINLP models are solved with meta-heurics or mathematical programming to acheive optimal work and heat integration.

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NIPS gif

Nonsolvent-induced Phase Separation (NIPS)

Model and simulation of microstructure formation in polymers via mass-transfer driven spinodal decomposition in ternary polymer solution.

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Publications


Title Citations Year
Mass-transfer driven spinodal decomposition in a ternary polymer solution

DR Tree, LF Dos Santos, CB Wilson, TR Scott, JU Garcia, GH Fredrickson

Soft matter 15 (23), 4614-4628, 2019

26 2019
Synthesis and optimization of work and heat exchange networks using an MINLP model with a reduced number of decision variables

LF Santos, CBB Costa, JA Caballero, MASS Ravagnani

Applied Energy 262, 114441, 2020

19 2020
Kriging-assisted constrained optimization of single-mixed refrigerant natural gas liquefaction process

LF Santos, CBB Costa, JA Caballero, MASS Ravagnani

Chemical Engineering Science 241, 116699, 2021

6 2021
Design and optimization of energy-efficient single mixed refrigerant LNG liquefaction process

LF Santos, CBB Costa, JA Caballero, MASS Ravagnani

Brazilian Journal of Chemical Engineering, 1-14, 2021

6 2021
Framework for embedding black-box simulation into mathematical programming via kriging surrogate model applied to natural gas liquefaction process optimization

LF Santos, CBB Costa, JA Caballero, MASS Ravagnani

Applied Energy, 310, 118537

2 2022
Search Space Analysis in Work and Heat Exchange Networks Synthesis using MINLP Models

LF Santos, CBB Costa, JA Caballero, MASS Ravagnani

Computer Aided Chemical Engineering 48, 1393-1398, 2020

1 2020
Multi-objective simulation optimization via kriging surrogate models applied to natural gas liquefaction process design

LF Santos, CBB Costa, JA Caballero, MASS Ravagnani

Energy, 125271

0 2022
MINLP model for work and heat exchange networks synthesis considering unclassified streams

LF Santos, CBB Costa, JA Caballero, MASS Ravagnani

Computer Aided Chemical Engineering 51, 793-798

0 2022
Multi-objective optimization of natural gas liquefaction process simulation via kriging surrogate model

LF Santos, CBB Costa, JA Caballero, MASS Ravagnani

Computer Aided Chemical Engineering 51, 793-798

0 2022
Framework for Embedding Process Simulator in GAMS via Kriging Surrogate Model Applied to C3MR Natural Gas Liquefaction Optimization

LF Santos, CBB Costa, JA Caballero, MASS Ravagnani

Chemical Engineering Transactions 88, 475-480

0 2021
Diffusion Driven Nonsolvent Induced Phase Separation

D Tree, LF Dos Santos, C Wilson, T Scott, JU Garcia, G Fredrickson

APS March Meeting Abstracts 2019, C25. 011, 2019

0 2019
Modeling the Effects of Mass Transfer on Microstructure Formation in Polymer Membranes

D Tree, LF Dos Santos, GH Fredrickson

2018 AIChE Annual Meeting

0 2018
Modeling the Effects of Mass Transfer on Microstructure Formation in Phase-Inversion Membranes

D Tree, LF Dos Santos, GH Fredrickson

2017 AIChE Annual Meeting

0 2017