Marius Brănoaea - Academia.edu (original) (raw)
Uploads
Papers by Marius Brănoaea
Materials, Mar 16, 2023
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Sciendo eBooks, Dec 31, 2020
Recently, the modern society has gained an increased interest in the concept of buildings energy ... more Recently, the modern society has gained an increased interest in the concept of buildings energy consumption and diverse studies regarding methods to reduce the buildings energy demand have been published in order to mitigate the impact buildings pose to the society, economy and environment. With their properties of being able to accumulate and release increased amounts of thermal energy, phase change materials (PCMs) present great potential. The implementation of a PCM into the heating system of a building can provide a substantial reduction in the energy demand for heating. Through CFD simulations this paper highlights that a reduction in the daily energy consumption for heating buildings can be achieved with the integration of PCMs through reducing the number of daily heating cycles and by increasing the discharge phase time the heating phase can be set during off peak periods taking advantage of the reduced energy price.
The 15th International Conference Interdisciplinarity in Engineering
Materials
The continuous growth of the concrete industry requires an increased quantity of cement and natur... more The continuous growth of the concrete industry requires an increased quantity of cement and natural aggregates year after year, and it is responsible for a major part of the global CO2 emissions. These aspects led to rigorous research for suitable raw materials. Taking into account that these raw materials must have a sustainable character and also a low impact on environmental pollution, the replacement of the conventional components of concrete by residual waste can lead to these targets. This paper’s aim is to analyze the density, compressive strength and the thermal conductivity of nine concrete compositions with various rates of waste: four mixes with 10%, 20%, 40% and 60% chopped PET bottles aggregates and 10% fly ash as cement partial substitution; a mix with 60% waste polystyrene of 4–8 mm and 10% fly ash; a mix with 20% waste polystyrene of 4–8 mm, 10% waste polystyrene of 0–4 mm and 10% fly ash; a mix with 50% waste polystyrene of 4–8 mm, 20% waste polystyrene of 0–4 mm an...
Bulletin of the Polytechnic Institute of Iași. Construction. Architecture Section, 2021
In the modern society the concept of energy efficiency of buildings has become a subject of great... more In the modern society the concept of energy efficiency of buildings has become a subject of great interest, due to the negative impact of buildings upon the environment, society and economy. One of the methods of overcoming this is to provide a better efficiency of the energy storage because it is the key to resolve the difference between supply and demand. In comparison to electro-chemical batteries which provide limited energy storage at a high financially cost, thus in this regard, thermal energy storage technologies with high energy density have increased market potential. PCMs present objective advantages in comparison to classic construction materials due to their characteristics of being able to store and release higher quantities of thermal energy during the phase change process. A PCM radiant floor heating system can provide a reduction of the energy consumption for heating by up to 43%, trough the higher discharge time of the PCM compared to regular heating systems.
Applied Sciences
One of the biggest challenges the world is facing these days is to reduce the greenhouse gases em... more One of the biggest challenges the world is facing these days is to reduce the greenhouse gases emissions in order to prevent the global warming. Since a significant quantity of CO2 emissions is the result of the energy producing process required in industry or buildings, the waste heat recovery is an important aspect in the fight for preserving the planet. In this study, an innovative waste heat recovery system which can recover waste heat energy from cooling liquids used in industry or in different processes, was designed and subjected to experimental investigations. The equipment uses heat pipes to capture thermal energy from the residual fluids transiting the evaporator zone and transfer it to the cold water transiting the condenser zone. The efficiency of the heat exchanger was tested in 9 scenarios, by varying the temperature of the primary agent to 60, 65 and 70 °C and the volume flow rate of the secondary agent to 1, 2 and 3 L/min. The temperature of the secondary agent and t...
Proceedings Of International Conference Building Services And Energy Efficiency
Recently, the modern society has gained an increased interest in the concept of buildings energy ... more Recently, the modern society has gained an increased interest in the concept of buildings energy consumption and diverse studies regarding methods to reduce the buildings energy demand have been published in order to mitigate the impact buildings pose to the society, economy and environment. With their properties of being able to accumulate and release increased amounts of thermal energy, phase change materials (PCMs) present great potential. The implementation of a PCM into the heating system of a building can provide a substantial reduction in the energy demand for heating. Through CFD simulations this paper highlights that a reduction in the daily energy consumption for heating buildings can be achieved with the integration of PCMs through reducing the number of daily heating cycles and by increasing the discharge phase time the heating phase can be set during off peak periods taking advantage of the reduced energy price.
Proceedings
The subject of buildings energy efficiency has gained increased interest in modern society. Recen... more The subject of buildings energy efficiency has gained increased interest in modern society. Recently, researchers aiming to reduce the energy demand of buildings have studied the implementation of phase change materials (PCMs) in various building elements. At the same time, researchers studied the implementation of unconventional technologies such as heat pipes (HP) in the buildings’ heating system. This paper combines both of these technologies in order to take advantage of the thermal storage properties of PCMs and overcome their reduced conductivity with heat pipes. Through computational fluid dynamics (CFD) simulations, this paper studies and highlights that with the implementation of a PCM, a reduction of the daily energy demand is achieved through the increase in the discharge phase time.
Proceedings Of International Conference Building Services And Energy Efficiency
Thermal energy recovery plays an important part when it comes to increasing the energy efficiency... more Thermal energy recovery plays an important part when it comes to increasing the energy efficiency of an industrial processes or of a building. The equipment used for heat recovery has undergone gradual improvements over time, one of the most significant being the introduction of heat pipes as part of their components. In order to optimize the functioning of heat recovery systems, it is important to use heat pipes suitable for the temperature and the nature of the heat source. This study consists of an experimental analysis of the filling ratios of copper heat pipes which are going to be used in the design of a heat recovery system. Distilled water is used as working fluid and the vacuum inside was made using a vacuum pump. A number of 20 heat pipes were designed and manufactured with 5 different filling ratios: 15 ml, 20 ml, 36 ml, 48 ml and 72 ml, the last one representing 50% of the internal volume of the shell. The evaporator of the heat pipes was introduced in hot water and the temperature variation on the adiabatic and the condenser zone was measured on different heights for one hour. The results showed that the tested thermosyphons have the best efficiency when the fill ratio is 25%.
Materials, Mar 16, 2023
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Sciendo eBooks, Dec 31, 2020
Recently, the modern society has gained an increased interest in the concept of buildings energy ... more Recently, the modern society has gained an increased interest in the concept of buildings energy consumption and diverse studies regarding methods to reduce the buildings energy demand have been published in order to mitigate the impact buildings pose to the society, economy and environment. With their properties of being able to accumulate and release increased amounts of thermal energy, phase change materials (PCMs) present great potential. The implementation of a PCM into the heating system of a building can provide a substantial reduction in the energy demand for heating. Through CFD simulations this paper highlights that a reduction in the daily energy consumption for heating buildings can be achieved with the integration of PCMs through reducing the number of daily heating cycles and by increasing the discharge phase time the heating phase can be set during off peak periods taking advantage of the reduced energy price.
The 15th International Conference Interdisciplinarity in Engineering
Materials
The continuous growth of the concrete industry requires an increased quantity of cement and natur... more The continuous growth of the concrete industry requires an increased quantity of cement and natural aggregates year after year, and it is responsible for a major part of the global CO2 emissions. These aspects led to rigorous research for suitable raw materials. Taking into account that these raw materials must have a sustainable character and also a low impact on environmental pollution, the replacement of the conventional components of concrete by residual waste can lead to these targets. This paper’s aim is to analyze the density, compressive strength and the thermal conductivity of nine concrete compositions with various rates of waste: four mixes with 10%, 20%, 40% and 60% chopped PET bottles aggregates and 10% fly ash as cement partial substitution; a mix with 60% waste polystyrene of 4–8 mm and 10% fly ash; a mix with 20% waste polystyrene of 4–8 mm, 10% waste polystyrene of 0–4 mm and 10% fly ash; a mix with 50% waste polystyrene of 4–8 mm, 20% waste polystyrene of 0–4 mm an...
Bulletin of the Polytechnic Institute of Iași. Construction. Architecture Section, 2021
In the modern society the concept of energy efficiency of buildings has become a subject of great... more In the modern society the concept of energy efficiency of buildings has become a subject of great interest, due to the negative impact of buildings upon the environment, society and economy. One of the methods of overcoming this is to provide a better efficiency of the energy storage because it is the key to resolve the difference between supply and demand. In comparison to electro-chemical batteries which provide limited energy storage at a high financially cost, thus in this regard, thermal energy storage technologies with high energy density have increased market potential. PCMs present objective advantages in comparison to classic construction materials due to their characteristics of being able to store and release higher quantities of thermal energy during the phase change process. A PCM radiant floor heating system can provide a reduction of the energy consumption for heating by up to 43%, trough the higher discharge time of the PCM compared to regular heating systems.
Applied Sciences
One of the biggest challenges the world is facing these days is to reduce the greenhouse gases em... more One of the biggest challenges the world is facing these days is to reduce the greenhouse gases emissions in order to prevent the global warming. Since a significant quantity of CO2 emissions is the result of the energy producing process required in industry or buildings, the waste heat recovery is an important aspect in the fight for preserving the planet. In this study, an innovative waste heat recovery system which can recover waste heat energy from cooling liquids used in industry or in different processes, was designed and subjected to experimental investigations. The equipment uses heat pipes to capture thermal energy from the residual fluids transiting the evaporator zone and transfer it to the cold water transiting the condenser zone. The efficiency of the heat exchanger was tested in 9 scenarios, by varying the temperature of the primary agent to 60, 65 and 70 °C and the volume flow rate of the secondary agent to 1, 2 and 3 L/min. The temperature of the secondary agent and t...
Proceedings Of International Conference Building Services And Energy Efficiency
Recently, the modern society has gained an increased interest in the concept of buildings energy ... more Recently, the modern society has gained an increased interest in the concept of buildings energy consumption and diverse studies regarding methods to reduce the buildings energy demand have been published in order to mitigate the impact buildings pose to the society, economy and environment. With their properties of being able to accumulate and release increased amounts of thermal energy, phase change materials (PCMs) present great potential. The implementation of a PCM into the heating system of a building can provide a substantial reduction in the energy demand for heating. Through CFD simulations this paper highlights that a reduction in the daily energy consumption for heating buildings can be achieved with the integration of PCMs through reducing the number of daily heating cycles and by increasing the discharge phase time the heating phase can be set during off peak periods taking advantage of the reduced energy price.
Proceedings
The subject of buildings energy efficiency has gained increased interest in modern society. Recen... more The subject of buildings energy efficiency has gained increased interest in modern society. Recently, researchers aiming to reduce the energy demand of buildings have studied the implementation of phase change materials (PCMs) in various building elements. At the same time, researchers studied the implementation of unconventional technologies such as heat pipes (HP) in the buildings’ heating system. This paper combines both of these technologies in order to take advantage of the thermal storage properties of PCMs and overcome their reduced conductivity with heat pipes. Through computational fluid dynamics (CFD) simulations, this paper studies and highlights that with the implementation of a PCM, a reduction of the daily energy demand is achieved through the increase in the discharge phase time.
Proceedings Of International Conference Building Services And Energy Efficiency
Thermal energy recovery plays an important part when it comes to increasing the energy efficiency... more Thermal energy recovery plays an important part when it comes to increasing the energy efficiency of an industrial processes or of a building. The equipment used for heat recovery has undergone gradual improvements over time, one of the most significant being the introduction of heat pipes as part of their components. In order to optimize the functioning of heat recovery systems, it is important to use heat pipes suitable for the temperature and the nature of the heat source. This study consists of an experimental analysis of the filling ratios of copper heat pipes which are going to be used in the design of a heat recovery system. Distilled water is used as working fluid and the vacuum inside was made using a vacuum pump. A number of 20 heat pipes were designed and manufactured with 5 different filling ratios: 15 ml, 20 ml, 36 ml, 48 ml and 72 ml, the last one representing 50% of the internal volume of the shell. The evaporator of the heat pipes was introduced in hot water and the temperature variation on the adiabatic and the condenser zone was measured on different heights for one hour. The results showed that the tested thermosyphons have the best efficiency when the fill ratio is 25%.