RAMIN MORADI

PhD Graduate

PhD program:: XXXIII


co-supervisor: Prof. Emanuele Habib

Thesis title: Object-oriented modeling of micro-ORC systems for low-grade waste heat recovery applications

Organic Rankine Cycle (ORC) systems are one of the most suitable technologies to produce electricity from low-temperature sources. A comprehensive understanding of these systems is necessary for their further deployment especially in micro scales, in which the intrinsic issues such as low isentropic efficiency and unreliability arise more severely. In this thesis, the components of a non-regenerative, micro-scale ORC unit are modeled empirically using the experimental data. The components models are used as functions in the system-level solver. The system solver uses a novel approach, in which no assumption is made for the modeling and only the components specifications and the real system boundaries that an operator has during the system run are put as inputs. This assumption-free, object-oriented model follows the two fundamental conservation laws of thermodynamics that are the conservation of energy and the conservation of mass. The developed mass-sensitive model is a robust solver that leads to a full understanding of the system limitations and losses using the empirical models of the main system components. In addition to the system modeling, the thesis theoretically studies the impact of the expander lubricant oil on the system performance using the empirical lubricant-refrigerant miscibility model and a data reconciliation method. The impact of the expander’s lubricant is found significantly effective on the performances of the heat exchangers, the expander, and the overall system especially in micro-scales, despite its influence has been mostly neglected in the literature so far. Since the use of micro-scale ORC systems for low-temperature waste heat recovery (WHR) applications is investigated, a novel kind of expander for such systems has been here analyzed using computational fluid dynamics (CFD). The regenerative flow turbine (RFT) is found particularly interesting due to its good and reliable performance in very low-pressure ratios making the machine suitable as an alternative expansion. Finally, a biomass-fed integrated system is studied in detail. The integrated system consists of a dual-fluidized-bed gasifier, a hot gas conditioning unit, a steam-injected-micro gas turbine, and an ORC as the bottom cycle. This system-level study shows the performance of the integrated system when full conservation of energy and mass is applied. The results show that the overall system efficiency improvement by the ORC is limited to 1-2 % using the wet gas turbine compared to 5-8% without the steam injection. Nevertheless, the produced thermal power in the condenser of the ORC unit shows the ability of the integrated system to meet higher users’ thermal demands in small-scale CHP applications.

Research products

11573/1682263 - 2021 - Assumption-free modeling of a micro-scale organic Rankine cycle system based on a mass-sensitive method
Moradi, R; Habib, E; Villarini, M; Cioccolanti, L - 01a Articolo in rivista
paper: ENERGY CONVERSION AND MANAGEMENT (Elsevier Science Limited:Oxford Fulfillment Center, PO Box 800, Kidlington Oxford OX5 1DX United Kingdom:011 44 1865 843000, 011 44 1865 843699, EMAIL: asianfo@elsevier.com, tcb@elsevier.co.UK, INTERNET: http://www.elsevier.com, http://www.elsevier.com/locate/shpsa/, Fax: 011 44 1865 843010) pp. 1-19 - issn: 0196-8904 - wos: WOS:000693364500004 (7) - scopus: 2-s2.0-85111274387 (8)

11573/1504684 - 2021 - Component-oriented modeling of a micro-scale organic rankine cycle system for waste heat recovery applications
Moradi, Ramin; Habib, Emanuele; Bocci, Enrico; Cioccolanti, Luca - 01a Articolo in rivista
paper: APPLIED SCIENCES (Basel: MDPI AG, 2011-) pp. 1-34 - issn: 2076-3417 - wos: WOS:000627985400001 (11) - scopus: 2-s2.0-85101817623 (14)

11573/1510779 - 2021 - Experimental modeling of a lubricated, open drive scroll expander for micro-scale organic Rankine cycle systems
Moradi, Ramin; Villarini, Mauro; Cioccolanti, Luca - 01a Articolo in rivista
paper: APPLIED THERMAL ENGINEERING (-Oxford : Elsevier Science Limited -Oxford: Pergamon.) pp. 1-13 - issn: 1359-4311 - wos: WOS:000640357800024 (20) - scopus: 2-s2.0-85101841308 (26)

11573/1501322 - 2021 - Impact of the expander lubricant oil on the performance of the plate heat exchangers and the scroll expander in a micro-scale organic Rankine cycle system
Moradi, Ramin; Villarini, Mauro; Habib, Emanuele; Bocci, Enrico; Colantoni, Andrea; Cioccolanti, Luca - 01a Articolo in rivista
paper: APPLIED THERMAL ENGINEERING (-Oxford : Elsevier Science Limited -Oxford: Pergamon.) pp. 1-17 - issn: 1359-4311 - wos: WOS:000635629300042 (13) - scopus: 2-s2.0-85101139491 (17)

11573/1359704 - 2020 - Integrating biomass gasification with a steam-injected micro gas turbine and an Organic Rankine Cycle unit for combined heat and power production
Moradi, R.; Marcantonio, V.; Cioccolanti, L.; Bocci, E. - 01a Articolo in rivista
paper: ENERGY CONVERSION AND MANAGEMENT (Elsevier Science Limited:Oxford Fulfillment Center, PO Box 800, Kidlington Oxford OX5 1DX United Kingdom:011 44 1865 843000, 011 44 1865 843699, EMAIL: asianfo@elsevier.com, tcb@elsevier.co.UK, INTERNET: http://www.elsevier.com, http://www.elsevier.com/locate/shpsa/, Fax: 011 44 1865 843010) pp. - - issn: 0196-8904 - wos: WOS:000515440100077 (45) - scopus: 2-s2.0-85077656677 (51)

11573/1435152 - 2020 - Investigation on the use of a novel regenerative flow turbine in a micro-scale Organic Rankine Cycle unit
Moradi, Ramin; Habib, Emanuele; Bocci, Enrico; Cioccolanti, Luca - 01a Articolo in rivista
paper: ENERGY (-Oxford: Elsevier Science Limited -Oxford; New York: Pergamon Press) pp. - - issn: 0360-5442 - wos: WOS:000606796000023 (14) - scopus: 2-s2.0-85089518829 (18)

11573/1319402 - 2019 - Numerical investigation on the performance of a regenerative flow turbine for small-scale organic Rankine cycle systems
Moradi, Ramin; Cioccolanti, L.; Bocci, E.; Villarini, M.; Renzi, M. - 01a Articolo in rivista
paper: JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER (New York N.Y.: American Society of Mechanical Engineers,) pp. - - issn: 0742-4795 - wos: WOS:000486648400015 (5) - scopus: 2-s2.0-85068930038 (7)

11573/1319418 - 2019 - Performance of a small-scale organic rankine cycle system using a regenerative flow turbine: a simulation analysis
Moradi, Ramin; Cioccolanti, Luca; Habib, Emanuele; Bocci, Enrico - 04b Atto di convegno in volume
conference: 5th International Seminar on ORC Power Systems (Athens, Greece)
book: Proceedings of the 5th International Seminar on ORC Power Systems - (978-90-9032038-0)

11573/1319412 - 2019 - Comparison between 1-D and grey-box models of a SOFC
Moradi, Ramin; Di Carlo, Andrea; Testa, Federico; Del Zotto, Luca; Bocci, Enrico; Habib, Emanuele - 04c Atto di convegno in rivista
paper: E3S WEB OF CONFERENCES (Les Ulis : EDP Sciences, 2013-) pp. - - issn: 2267-1242 - wos: WOS:000543713200007 (1) - scopus: 2-s2.0-85075493628 (1)
conference: International Conference on Computational Heat, Mass and Momentum Transfer (ICCHMT2019) (Rome, Italy)

11573/1319409 - 2019 - Analysis of a micro-CHP system consisting of steam injected gas turbine fed by syngas and integrated with bottoming Organic Rankine Cycle
Moradi, Ramin; Luca, Cioccolanti; Monforti Ferrario, Andrea; Habib, Emanuele; Bocci, Enrico - 04b Atto di convegno in volume
conference: 32nd international conference on efficiency, cost, optimization, simulation and environmental impact of energy systems, ECOS 2019 (Inglese)
book: 32nd international conference on efficiency, cost, optimization, simulation and environmental impact of energy systems - (978-83-61506-51-5)

11573/1227441 - 2018 - Thermodynamic simulation of a small-scale organic Rankine cycle testing facility using R245fa
Moradi, Ramin; Tascioni, Roberto; Habib, Emanuele; Cioccolanti, Luca; Villarini, Mauro; Bocci, Enrico - 04c Atto di convegno in rivista
paper: ENERGY PROCEDIA (Oxford: Elsevier B.V) pp. 66-73 - issn: 1876-6102 - wos: WOS:000480453000009 (7) - scopus: 2-s2.0-85056611430 (10)
conference: 73rd Conference of the Italian Thermal Machines Engineering Association (ATI 2018) (Pisa, Italy)

11573/1123663 - 2017 - Optimization of a solar air heater with phase change materials: Experimental and ‎numerical study
Moradi, Ramin; Kianifar, A; Wongwises, S - 01a Articolo in rivista
paper: EXPERIMENTAL THERMAL AND FLUID SCIENCE (Elsevier Science Incorporated / NY Journals:Madison Square Station, PO Box 882:New York, NY 10159:(212)633-3730, EMAIL: usinfo-f@elsevier.com, INTERNET: http://www.elsevier.com, Fax: (212)633-3680) pp. 41-49 - issn: 0894-1777 - wos: WOS:000413387500004 (85) - scopus: 2-s2.0-85026757165 (98)

11573/1123764 - 2013 - The Numerical Study of the Gas-Solid Flow in a Conventional Cyclone Separator
Moradi, Ramin; Deyranlou, A; Moghiman, M - 04f Poster
conference: 15th Conference On Fluid Dynamics (The University of Hormozgan, Bandar Abbas, Iran)
book: 15th Conference On Fluid Dynamics, fd2013 - ()

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