Giuntini Lorenzo

Family Name: Giuntini

Name: Lorenzo

Date of Birth: 08/10/1994

Place of Birth: Empoli

Linkedin: https://www.linkedin.com/in/lorenzo-giuntini-16a280125/

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Orcid ID https://orcid.org/0000-0003-2284-2105

PhD Program: Industrial Engineering

Curriculum: Materials and Chemical Engineering

Date of issue of the PhD certificate: 15/03/2024

Supervisors: Prof. Galletti Chiara, Prof. Tognotti Leonardo.

Co-supervisor: Prof. Nicolella Cristiano

Subsequent evaluation: Excellent cum laude

Final exam board (Name, Family Name and relevant department):

Antonio Attili, The University of Edinburgh

Christoph Hochenauer, Graz University of Technology

Alessandro Parente, Université Libre de Bruxelles

Mara De Joannon, Istituto di Scienze e Tecnologie per l'Energia e la Mobilità Sostenibili, CNR

Leonardo Tognotti, Università di Pisa

Chiara Galletti, Università di Pisa

PhD cycle: XXXVI

Title of the PhD thesis: Advanced numerical modelling of energy generation using sustainable alternative fuels for a decarbonized scenario 

Abstract of the PhD thesis:  In the ongoing energy transition, advanced combustion technologies are crucial for the clean and efficient use of sustainable alternative fuels. This, however, requires that existing burners are modified and the new ones properly designed. In this process, numerical modeling is an indispensable tool, but available models may not be well-suited for simulating innovative combustion regimes and new fuels. Thus, continuous revisions and improvements are necessary. The aim of this Ph.D. thesis is twofold: i) to improve the state of the art on the numerical modeling of advanced combustion systems fueled by alternative fuels; ii) to propose simple, i.e., cheap and easy-to-implement, solutions to revamp real combustors, thus enabling their decarbonization. Addressing these objectives resulted in several connected activities. i) A method to improve the micro-mixing treatment in Transported PDF models is presented and tested on a system emulating MILD combustion. The proposed method enables extending the applicability of TPDF closures to cases where prior knowledge of the combustion regime is limited. Additionally, it eliminates the need for laborious trial-and-error tuning of the mixing constant. ii) State-of-the-art combustion models are employed to simulate methane and ammonia MILD combustion in a system with internal recirculation. This work provides a useful overview on the performance of the available CFD sub-models and suggests numerical guidelines for simulating such an unconventional combustion regime. iii) A fossil-fuel-powered combustor is converted to burn ammonia in a staged rich-lean configuration. This study demonstrates with a real application that few geometric modifications to an existing system are sufficient to achieve complete and low-NOx combustion of ammonia. iv) A novel methodology for calibrating Chemical Reactor Network (CRN) models is introduced. This consists in a strategy that explicitly accounts for model error to calibrate the CRN parameters and to estimate the model’s structural uncertainty. Through the application of this approach, low-fidelity CRN models can generate predictions with error bars. This feature provides a measure of the model’s reliability/accuracy allowing a safe utilization of such reduced-order models. v) Eventually, an existing industrial-scale burner for tissue paper drying is converted from LPG to biomass-derived syngas fueling, thus defossilizing the plant. Minor modifications are devised to provide a complete fuel-flexibility to the combustion system, thereby enabling a smooth transition from 100% LPG to 100% bio-syngas. The proposed solution will allow saving approximately 8500 ton/y of CO2 emissions in comparison with today’s fossil fuel carbon footprint.

Teaching and Tutoring experience: 

Teaching activities

1. Course name: “Formazione e Controllo di Inquinanti nella Combustione” for Master’s students in Energy Engineering, 10 h, academic year 2020-2021
2. Course name: “Fluidodinamica Computazionale multifase e reattiva” for Master’s students in Chemical Engineering, 10 h, academic year 2022-2023
3.  “Autocad” course for Master’s students in Chemical Engineering, 3 h, academic year 2020-2021
4. “Autocad” course for Master’s students in Chemical Engineering, 3 h, academic year 2021-2022
5. “Autocad” course for Master’s students in Chemical Engineering, 3 h, academic year 2022-2023

Tutoring to Master’s thesis students

6. Claudia Genovese. Period: 06/2021 – 02/2022. Title: “Modellazione dei meccanismi di scambio e reazione di un combustore MILD ciclonico”
7. Marta Bernardeschi. Period: 01/2022 – 07/2022. Title: “Experimental characterization of renewable synthetic fuel combustion in a lab-scale gas turbine burner”
8. Alessio Botrini. Period: 05/2022 – 11/2022. Title: “Conversione energetica di idrogeno ed ammoniaca in condizioni di forte ricircolo interno
9. Chiara Novelli. Period: 01/2023 – 09/2023. Title: “Feeding sustainable alternative fuels to a micro gas turbine: validation of the numerical model”

Publications 

1. Giuntini, R. Lamioni, L. Linari, P. Saccomanno, D. Mainardi, L. Tognotti, C. Galletti, 2022. Decarbonization of a tissue paper plant: Advanced numerical simulations to assess the replacement of fossil fuels with a biomass-derived syngas. Renewable Energy, 198, 884-893.

2. Giuntini, L. Frascino, G.B. Ariemma, C. Galletti, G. Sorrentino, R. Ragucci, 2023. Performance Assessment of Modeling Approaches for Moderate or Intense Low-Oxygen Dilution Combustion in a Scale-Bridging Burner. Energy & Fuels, 37, 9500-9513.

3. Giuntini, L. Frascino, G.B. Ariemma, C. Galletti, G. Sorrentino, R. Ragucci, 2023. Modeling of Ammonia MILD Combustion in Systems with Internal Recirculation. Combustion Science and Technology, 195, 3513-3528 .

4. Savarese, L. Giuntini, R. Malpica Galassi, S. Iavarone, C. Galletti, W. De Paepe, A. Parente, 2023. Model-to-model Bayesian calibration of a Chemical Reactor Network for pollutant emission predictions of an ammonia-fuelled multistage combustor. International Journal of Hydrogen Energy, 195, 3513-3528 .

5. Giuntini, M. Savarese, C. Galletti, A. Parente, 2023. Local estimation of the mixing model constant for transported PDF combustion models. Fuel, 357, 130022.

6. Giuntini, C. Novelli, M.M. Kamal, M. Cafiero, A. Coussement, A. Parente, 2024. Continuously-staged NH3 oxidation in a stagnation-point reverse-flow combustor for low NOx emissions. Proceedings of the Combustion Institute (under review).

7. Savarese, A. Procacci, S. Iavarone, L. Giuntini, W. De Paepe, A. Parente 2024. A sparse sensing and Chemical Reactor Network based framework for the development of physics-based digital twins of combustion devices. Proceedings of the Combustion Institute (under review).

8. Ozden, M. Savarese, L. Giuntini, A. Procacci, R. Malpica Galassi, A. Coussement, F. Contino, A. Parente, 2024. A multi-fidelity framework for developing digital twins of combustion systems from heterogeneous data: application to ammonia combustion. Proceedings of the Combustion Institute (under review).

Conferences

1. 10^th European Combustion Meeting (ECM 2021), Naples, Italy, 14-15/04/2021. L. Giuntini, A. Bertei, S. Tortorelli, M. Percivale, E. Paoletti, L. Tognotti, C. Nicolella, C. Galletti. “Investigation of a Regenerative Thermal Oxidizer for the Abatement of Volatile Organic Compounds”. (Poster session)
2. 43^rd Meeting of the Italian Section of the Combustion Institute, Ischia, Italy, 3-6/10/2021. G. Sorrentino, G.B. Ariemma, R. Ragucci, C. Genovese, L. Giuntini, C. Galletti, “Performance of modeling paradigms for the simulation of a cyclonic burner”
3. 18^th International Conference on Numerical Combustion, San Diego, USA, 8-11/5/2022.
4. 44^th Meeting of the Italian Section of the Combustion Institute, Naples, Italy, 5-8/6/2022.
   a.  L. Giuntini, C. Genovese, C. Galletti, L. Frascino, G.B. Ariemma, G. Sorrentino, R. Ragucci, “Performance assessment of numerical models for the simulation of a cyclonic burner fed with methane” (Oral presentation)

b.  L. Giuntini, M. Savarese, C. Galletti, A. Parente, “On the dynamic determination of the micro-mixing constant in Transported joint-composition PDF models” (Oral presentation)

5. 2^nd International Workshop on MILD Combustion: modelling challenges, experimental configurations and diagnostic tools, Naples, Italy, 8-9/6/2022
   1. Giuntini, C. Genovese, C. Galletti, L. Frascino, G.B. Ariemma, G. Sorrentino, R. Ragucci, “Performance assessment of numerical models for the simulation of a cyclonic burner fed with methane” (Oral presentation)
   2. Giuntini, M. Savarese, C. Galletti, A. Parente, “On the dynamic determination of the micro-mixing constant in Transported joint-composition PDF models”(Oral presentation)
6. 12^th Mediterranean Combustion Symposium (MCS12), Luxor, Egypt, 23-26/01/2023. Giuntini, L., Frascino, L., Ariemma, G.B., Galletti, C., Sorrentino, G., Ragucci, R., “Modeling approaches for ammonia MILD combustion in a system with internal recirculation”. (Oral presentation)
7. 11^th European Combustion Meeting (ECM 2023), Rouen, France, 26-28/04/2023. Giuntini, L., Savarese, M., Galletti, C., Parente, A., “Numerical design of a rich-lean micro-Gas Turbine combustor for ammonia fueling”. (Poster session)
8. Joint Meeting of the Belgian and Italian Sections of The Combustion Institute + 1st Italian Workshop on Ammonia Energy, Florence, Italy, 28-31/05/2023. Giuntini, L., Galletti, C., Parente, A., “Numerical design of a rich-lean micro-Gas Turbine combustor for ammonia fueling”. (Oral presentation)
9. 2^nd Symposium on Ammonia Energy, Orléans, France, 11-13/07/2023. Giuntini, L., Cafiero, M., Kamal, M.M., Galletti, C., Parente, A., “Numerical design of a rich-lean micro-Gas Turbine combustor for ammonia fueling”. (Oral presentation)

Courses and PhD schools

1. “English for Research Publication and Presentation Purposes” C1 level, Prof. Joanne Spataro. January - March 2021 (30 h).
2. “Introduction to uncertainty quantification and stochastic sensitivity analysis”, Prof. Alessandro Mariotti. January - February 2021 (12 h);
3. “GRICU PhD School 2021 | Digitalization Tools for the Chemical and Process Industries”. March 2021 (16 h).
4. “Combustion”, Prof. Alessandro Parente. March - May 2021 (30 h).
5. “Turbulent combustion”, Von Karman Institute. May 2021 (26 h)
6. “Neural networks and Deep Learning”, Prof. Beatrice Lazzerini. June - July 2021 (11 h);
7. “French course A1 level”, Prof. Bernard Levy (CLI). March - June 2021 (60 h);
8. “English for Research Publication and Presentation Purposes” C1+ level, Prof. Joanne Spataro. October - December 2021 (30 h).
9. “ERCOFTAC/JMBC Combustion Winter School: Towards carbon-neutral combustion systems”. January - February 2022, University of Technology, Eindhoven, The Netherlands (26h).
10. “GRICU PhD School 2022 | Catalysis and Catalytic Reaction Engineering, Electrochemical Energy Conversion and Storage: from thermodynamics and kinetics to devices”. July 2022, Ischia, Italy (21 h).
11. “English Level C1 course”, Prof. Steven Smith (CLI). October 2021 - July 2022 (120 h).
12. “Understanding and Predicting Hydrogen Combustion”, November - December 2022, Barcelona Supercomputing Center, Spain (20h).
13. “English course for IELTS exam”, Prof. Leigh Anne Wendy Mazzoncini (CLI). October - December 2022 (30 h).