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Prof. Dr. Hélio Augusto Goulart Diniz
Department of Electromechanics, Federal Center for Technological Education of Minas Gerais, Belo Horizonte, Minas Gerais, Brazil
Professor and Researcher in Mechanical Engineering at the Fe...
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Academic Career Length
7Years (2020-Present)
(Calculated once Scilit publication data is synced: current year − year of first publication + 1)
Representative Publications
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Journal Article
HDHélio Augusto Goulart Diniz
Hélio Augusto Goulart DinizTPTiago Freitas Paulino
Tiago Freitas Paulino
Juan Jose Garcia PabonAMANTONIO AUGUSTO TORRES MAIA
ANTONIO AUGUSTO TORRES MAIA
Raphael NunesThis paper presents a distributed mathematical model for a carbon dioxide direct expansion solar-assisted heat pump used to heat bath water. The main components are a gas cooler, a needle valve, an evaporator/collector, and a compressor. To develop the heat exchange models, mass, energy, and momentum balances were used. The model was validated for transient as well as steady state conditions using experimental data. A reasonably good agreement was observed between the predicted temperatures and experimental data. The simulations showed that the time step required to demonstrate the behavior of the heat pump in the transient regime is greater than the time step required for the steady state. The results obtained with the mathematical model revealed that a reduction in the water mass flow rate results in an increase in the water outlet temperature. In addition, when the carbon dioxide mass flow rate is reduced, the compressor inlet and outlet temperatures increase as well as the water outlet temperature.
25 July 2023 in International Journal of Refrigeration
Journal Article
HDHélio Augusto Goulart Diniz
Hélio Augusto Goulart DinizSRSara Isabel de Melo Resende
Sara Isabel de Melo Resende
ALArthur Pacheco Luz
Arthur Pacheco Luz
LMLuiz Machado
Luiz Machado
RORaphael Nunes de Oliveira
Raphael Nunes de Oliveira
12 June 2023 in Solar Energy
Journal Article
HDHélio Augusto Goulart Diniz
Hélio Augusto Goulart DinizSRSara Isabel de Melo Resende
Sara Isabel de Melo Resende
AMAntônio Augusto Torres Maia
Antônio Augusto Torres Maia
LMLuiz Machado
Luiz Machado
RORaphael Nunes de Oliveira
Raphael Nunes de Oliveira
1 June 2024 in International Journal of Refrigeration
Journal Article
ALArthur Pacheco Luz
Arthur Pacheco Luz
HDHélio Augusto Goulart Diniz
Hélio Augusto Goulart DinizDDDuarte Moreira Duarte
Duarte Moreira DuarteLMLuiz Machado
Luiz Machado
Journal Article
SRSara Isabel de Melo Resende
Sara Isabel de Melo ResendeHDHélio Augusto Goulart Diniz
Hélio Augusto Goulart DinizRFRalney Nogueira Faria
Ralney Nogueira FariaRORaphael Nunes De Oliveira
Raphael Nunes De OliveiraGiven the growing demand for sustainable energy solutions, this study addresses the challenge of improving the efficiency and environmental performance of residential water heating systems. This work presents the design and implementation of a controller aimed at regulating the outlet water temperature of a direct-expansion solar-assisted heat pump operating with propane. A dynamic model was experimentally identified using the AutoRegressive with eXogenous input methodology and used to design a Proportional–Integral–Derivative controller via the direct synthesis method. To regulate the outlet water temperature, the controller acts on the water flow rate. The effectiveness of the controller was evaluated through computer simulations and experimental tests. Its robustness was assessed by considering parametric variations of ±15%, during which the system maintained stability and performance. The controller demonstrated good accuracy and performance, keeping the desired temperature stable even in the presence of disturbances, both in simulations and experimental evaluations.
26 December 2024 in Journal of Building Engineering
Journal Article
SRSara Isabel de Melo Resende
Sara Isabel de Melo ResendeHDHélio Augusto Goulart Diniz
Hélio Augusto Goulart DinizLMLuiz Machado
Luiz Machado
RFRalney Nogueira de Faria
Ralney Nogueira de Faria
RORaphael Nunes de Oliveira
Raphael Nunes de Oliveira
About Me
Mechanical Engineer (B.Sc.) and holds an M.Sc. and a Ph.D. in Mechanical Engineering from the Federal University of Minas Gerais (UFMG), Brazil, with a concentration in Energy and Sustainability. He completed a postdoctoral appointment at UFMG and is currently pursuing a second postdoctoral appointment at the Pontifical Catholic University of Minas Gerais (PUC Minas), in the area of Thermal and Fluid Systems. From 2016 to 2025, he served as a faculty member in Mechanical Engineering programs at UFMG, the Minas Gerais State University (UEMG), Centro Universitário Estácio, and Faculdade Pitágoras. Between 2015 and 2025, he conducted research at UFMG and UEMG, focusing on heat exchangers, refrigeration systems, and heat pump technologies. In 2026, he joined the Federal Center for Technological Education of Minas Gerais (CEFET-MG) as a tenured faculty member and currently serves as Assistant Professor in the Department of Electromechanics. Since 2026, he has also been a Permanent Faculty Member of the Graduate Program in Mechanical Engineering (PPGEM) at CEFET-MG, where he conducts research within the Refrigeration, Heating and Air Conditioning Research Group (GRAC).
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