Nomenclature: A: the surface of building losses-(m²); C P : the air specific heat-(Wh/m³ K); CDD:... more Nomenclature: A: the surface of building losses-(m²); C P : the air specific heat-(Wh/m³ K); CDD: cooling degree day-(°C day); HDD: Heating Degree Day-(°C day); ks: the coefficient of total thermal transmission-(W/m² K); Q heat, Net : Net energy needs for heating-(MJ); Q L, heat : heat losses by transmission and ventilation during heating period-(MJ); Q cool, net : Net energy needs for cooling-(MJ); Q L, cool : heat losses by transmission and ventilation during cooling period-(MJ); Q g,cool : heat gain by radiation and internal heat production during cooling period-(MJ); Q g,heat : heat gain by radiation and heat internal production during heating period-(MJ); V: the air volume included in dwelling-(m³); T: temperature-(°C); β: the ventilation rate of dwelling-(h-1); η : the utilization factor.
Tertiary habitat is the largest consumer of energy sector in Algeria. This corresponds to almost ... more Tertiary habitat is the largest consumer of energy sector in Algeria. This corresponds to almost 41% of national consumption. Final consumption in the residential sector reached 6 million tep in 2005. In this article, the results are analyzed after renovations made on a bungalow tourist complex located in Hammam Righa (100 km southwest of Algiers). The most important aspects for better energy performance of a building have been considered in this project. The calculations of thermal balances are made under the RETA software, according to the standards of the technical document DTR (C2-3), modeling the type of bungalow 5.5 using TRNSYS17 software. The results obtained show that after renovation of the bungalows, ambient temperatures are between 15 ° C and 20 ° C in winter and 25 ° C to 30 ° C in summer.
Dans beaucoup de pays développés et en voie de développement, le secteur du bâtiment représente 2... more Dans beaucoup de pays développés et en voie de développement, le secteur du bâtiment représente 25% à 40% de la consommation énergétique. Cet article présente les résultats d'une étude expérimentale faite sur une habitation prototype, efficace énergétiquement, et munie d'un dispositif de chauffage innovant. Le dispositif est un système solaire combiné qui permet, grâce à des capteurs solaires, de chauffer l'habitation et de produire de l'eau chaude sanitaire. Abstract -In many developed and developing countries, the building sector accounts for 25% to 40% of energy consumption. The aim of this article is to present the results of an experimental study on a prototype dwelling fitted with an innovative heating system. The device is a combined solar system which, through solar collectors is capable of providing space heating as well as domestic hot water. Mots clés: Bâtiment -Efficacité énergétique -Système combiné -Plancher chauffant.
The present work aims to model heat and mass transfer through wooden building walls in Nancy. Ads... more The present work aims to model heat and mass transfer through wooden building walls in Nancy. Adsorption and desorption isotherms of three exotic wood and one temperate wood using a dynamic vapor sorption apparatus at 35°C were experimentally determined then modelled using Nelson sorption isotherm model. Sorption hysteresis of these woods was deduced. Heat and mass transfer model validation shows that the thickness of wooden wall higher than 0.15 m permits to cancel the influences of ambient air temperature on the temperature of the air in the building. Also, the results show that influence of the four wood species is not observed and can be neglected. To reduce the quantity of water absorbed by the wooden wall, it is important to dry the plank to a moisture content of 0.14 kg/kg dry basis. It is observed that heat and mass transfer gradients are highly influenced by the seasonal variations and characteristics of indoor air. During the day, the wooden wall gives a low variation of c...
Résumé – Cet article comporte deux parties, la première consiste à dimensionner, réaliser et expé... more Résumé – Cet article comporte deux parties, la première consiste à dimensionner, réaliser et expérimenter une installation de chauffage d’eau collectif d'une capacité de 400 litres. La deuxième partie est consacrée à l'étude du système d'appoint et l'influence du coût de cette énergie sur l'optimisation et le dimensionnement de l'installation. Abstract – This article includes two parts, the first one consists of the dimensioning, realisation and experimentation of a collective solar water heating installation having capacity of a 400 litres. The second part concerns the study of the auxiliary system and the cost influence of this energy on the installation optimisation and dimensioning.
The purpose of a bioclimatic house is to make every effort to reduce the need for heating and coo... more The purpose of a bioclimatic house is to make every effort to reduce the need for heating and cooling. For this a well studied architecture of the house is essential: - the positioning of windows to capture the maximum solar radiation, - Good thermal insulation of the house to reduce heat loss. This study focuses on the effect of solar and internal heat gain on the energy consumption of a typical well insulated house. The degree day's method is used to determine the heat losses by transmission and ventilation according to international standards on thermal insulation of building (NBN B62-301), the results are very interesting and promising. By including the solar and internal gains, which vary from 900 to 1400 kWh, the energy consumption decreases significantly. The thermal load for heat reaches 60 kWh, but by including the free thermal gains, 10 kWh of energy can be saved daily. Resume - L'objectif d'une maison bioclimatique est de tout mettre en œuvre pour reduire les ...
The purpose of this work concerns the study of the insulation effect upon the thermal behavior of... more The purpose of this work concerns the study of the insulation effect upon the thermal behavior of a house built with local materials according to Algerian building standard. In this regard, some simulations have been performed using the energy simulation software package ‘TRNSYS 16’ with the numerical model type 56. Our project involves the introduction of insulating materials in a building, so as to improve the thermal comfort and reduce the consumed energy. Different solutions and variants were proposed, in order to make a relevant choice, ensuring the best thermal comfort of a house while being as less energy-greedy as possible.
Wind energy is an important part of renewable energy sources in many countries. In the last decad... more Wind energy is an important part of renewable energy sources in many countries. In the last decades, the flow simulation for wind turbines have been studied more because it is a very good alternative for producing energy. The community of researches is normally focused on studying behavior and performance of wind farms, spectral contents of the power fluctuations, different methods of quantifying effects of turbulence-generated loads on wind turbine blade, influence of atmospheric turbulence on the fatigue loads. This paper is focused on turbulent flow modeling for 2 and 12 wind model turbines using Large-eddy simulation and Lagrangian-averaged scale-independent dynamic Smagorinsky model. Analyses of vortex behavior along turbine wake and analyses of normalized horizontal velocity profiles behind the wind turbine, as well as fractal dimension calculation for turbulent wake were performed using ImaCalc program. Normalized horizontal velocity profiles were compared with experimental r...
A significant portion of energy consumed in buildings is due to energy usage by heating, ventilat... more A significant portion of energy consumed in buildings is due to energy usage by heating, ventilation, and air conditioning (HVAC) systems. Free cooling is a good option for energy savings in (HVAC) systems. In recent years, scientists, engineers, and architects designed successful and innovative buildings which use passive cooling techniques, such as natural ventilation. The house studied in the present work, is a pilot project undertaken jointly by the Centre for Development of Renewable Energies (CDER) and the National Centre for Studies and Research of the integrated building (CNERIB) in the framework of the MED-ENEC project (Mediterranean Energy Efficiency in Construction structure). The house under consideration has a surface area of 65 m² and is located in the region of Algiers which characterized by a Mediterranean climate with relatively mild winters and a hot and humid summer. The aim of this work is to study the thermal comfort inside the house in summer without air condi...
The hygrothermal transfer is very important for the design of a building envelope for thermal com... more The hygrothermal transfer is very important for the design of a building envelope for thermal comfort and economic and energy analysis of the building envelope. The applications of various materials in building envelope have been studied extensively. The study presents several models for the hygrothermal transfer for various building walls. Several energy and mass conservation equations with different boundary conditions and input considerations were presented in this paper for concrete, bricks and wooden walls. The effect of hysteresis was ignored in developing most model equations, while few considered flow pattern of fluid through the wall surfaces. Due to the flexibility of Luikov models, it formed the basis for modelling the coupled heat and mass transfer for porous material independent of hygroscopic nature with different boundary conditions defined according to the geometry and orientations. The influence of type of wall, orientation, thickness, the density of the material an...
The passive solar house is designed to prevent heat loss and to maximize thermal input from the s... more The passive solar house is designed to prevent heat loss and to maximize thermal input from the sun. Our study focuses on the effect of solar and internal heat gain on energy consumption of a typical well insulated house. The degree day's method was used to determine the heat losses by transmission and ventilation according to international standards on thermal insulation of building (NBN B62-301). It was found that the results of the study are very interesting and promising. By including the solar and internal gains, varied from 900 to 1400 kWh, it was indicated that the energy consumption decreased significantly. The thermal load for heat reached 60 kWh, but by including the free thermal gains, 10 kWh of energy was saved per day.
The passive solar house is designed to prevent heat loss and to maximize thermal input from the s... more The passive solar house is designed to prevent heat loss and to maximize thermal input from the sun. Our study focuses on the effect of solar and internal heat gain on energy consumption of a typical well insulated house. The degree day's method was used to determine the heat losses by transmission and ventilation according to international standards on thermal insulation of building (NBN B62-301). It was found that the results of the study are very interesting and promising. By including the solar and internal gains, varied from 900 to 1400 kWh, it was indicated that the energy consumption decreased significantly. The thermal load for heat reached 60 kWh, but by including the free thermal gains, 10 kWh of energy was saved per day.
The building's form and thermal characteristics largely govern the amount of energy consumed by a... more The building's form and thermal characteristics largely govern the amount of energy consumed by a building. To avoid major flaws of the design, an architect needs to include the evaluation of the building's energy consumption in the earlier stages of the design process. If energy efficiency is not adequately considered during these stages, higher operating cost will accrue over the life of the building. In recent years, scientists, engineers and architects designed successful innovative buildings that use passive cooling techniques, such as natural ventilation. The house studied is a pilot project undertaken jointly by the Centre for Development of Renewable Energies (CDER) and the National Centre for Studies and Research of integrated building (CNERIB) under the MED-ENEC project (Mediterranean Energy Efficiency in Construction structure). The house subject of study is 65 m² surface area, located in the Algiers region characterized by a Mediterranean climate with relatively mild winters and hot, humid summer. This work is to study the comfort inside the house in the summer without air conditioning, ventilation only is considered. Numerical simulation is made under TRNSYS, the results compared with measured values are conclusive.
Tertiary habitat is the largest consumer of energy sector in Algeria. This corresponds to almost ... more Tertiary habitat is the largest consumer of energy sector in Algeria. This corresponds to almost 41% of national consumption. Final consumption in the residential sector reached 6 million tep in 2005. In this article, the results are analyzed after renovations made on a bungalow tourist complex located in Hammam Righa (100 km southwest of Algiers). The most important aspects for better energy performance of a building have been considered in this project. The calculations of thermal balances are made under the RETA software, according to the standards of the technical document DTR (C2-3), modeling the type of bungalow 5.5 using TRNSYS17 software. The results obtained show that after renovation of the bungalows, ambient temperatures are between 15 ° C and 20 ° C in winter and 25 ° C to 30 ° C in summer.
A significant portion of energy consumed in buildings is due to energy usage by heating, ventilat... more A significant portion of energy consumed in buildings is due to energy usage by heating, ventilation, and air conditioning systems. Free cooling is a good option for energy savings in the systems. In recent years, scientists, engineers, and architects designed successful and innovative buildings which use passive cooling techniques, such as natural ventilation. The house studied in the present work, is a pilot project undertaken jointly by the Centre for Development of Renewable Energies (CDER) and the National Centre for Studies and Research of the integrated building (CNERIB) in the framework of the MED-ENEC project (Mediterranean Energy Efficiency in Construction structure). The house under consideration has a surface area of 65 m2 and is located in the region of Algiers which characterized by a Mediterranean climate with relatively mild winters and a hot and humid summer. The aim of this work is to study the thermal comfort inside the house in summer without air conditioning sys...
Nomenclature: A: the surface of building losses-(m²); C P : the air specific heat-(Wh/m³ K); CDD:... more Nomenclature: A: the surface of building losses-(m²); C P : the air specific heat-(Wh/m³ K); CDD: cooling degree day-(°C day); HDD: Heating Degree Day-(°C day); ks: the coefficient of total thermal transmission-(W/m² K); Q heat, Net : Net energy needs for heating-(MJ); Q L, heat : heat losses by transmission and ventilation during heating period-(MJ); Q cool, net : Net energy needs for cooling-(MJ); Q L, cool : heat losses by transmission and ventilation during cooling period-(MJ); Q g,cool : heat gain by radiation and internal heat production during cooling period-(MJ); Q g,heat : heat gain by radiation and heat internal production during heating period-(MJ); V: the air volume included in dwelling-(m³); T: temperature-(°C); β: the ventilation rate of dwelling-(h-1); η : the utilization factor.
Tertiary habitat is the largest consumer of energy sector in Algeria. This corresponds to almost ... more Tertiary habitat is the largest consumer of energy sector in Algeria. This corresponds to almost 41% of national consumption. Final consumption in the residential sector reached 6 million tep in 2005. In this article, the results are analyzed after renovations made on a bungalow tourist complex located in Hammam Righa (100 km southwest of Algiers). The most important aspects for better energy performance of a building have been considered in this project. The calculations of thermal balances are made under the RETA software, according to the standards of the technical document DTR (C2-3), modeling the type of bungalow 5.5 using TRNSYS17 software. The results obtained show that after renovation of the bungalows, ambient temperatures are between 15 ° C and 20 ° C in winter and 25 ° C to 30 ° C in summer.
Dans beaucoup de pays développés et en voie de développement, le secteur du bâtiment représente 2... more Dans beaucoup de pays développés et en voie de développement, le secteur du bâtiment représente 25% à 40% de la consommation énergétique. Cet article présente les résultats d'une étude expérimentale faite sur une habitation prototype, efficace énergétiquement, et munie d'un dispositif de chauffage innovant. Le dispositif est un système solaire combiné qui permet, grâce à des capteurs solaires, de chauffer l'habitation et de produire de l'eau chaude sanitaire. Abstract -In many developed and developing countries, the building sector accounts for 25% to 40% of energy consumption. The aim of this article is to present the results of an experimental study on a prototype dwelling fitted with an innovative heating system. The device is a combined solar system which, through solar collectors is capable of providing space heating as well as domestic hot water. Mots clés: Bâtiment -Efficacité énergétique -Système combiné -Plancher chauffant.
The present work aims to model heat and mass transfer through wooden building walls in Nancy. Ads... more The present work aims to model heat and mass transfer through wooden building walls in Nancy. Adsorption and desorption isotherms of three exotic wood and one temperate wood using a dynamic vapor sorption apparatus at 35°C were experimentally determined then modelled using Nelson sorption isotherm model. Sorption hysteresis of these woods was deduced. Heat and mass transfer model validation shows that the thickness of wooden wall higher than 0.15 m permits to cancel the influences of ambient air temperature on the temperature of the air in the building. Also, the results show that influence of the four wood species is not observed and can be neglected. To reduce the quantity of water absorbed by the wooden wall, it is important to dry the plank to a moisture content of 0.14 kg/kg dry basis. It is observed that heat and mass transfer gradients are highly influenced by the seasonal variations and characteristics of indoor air. During the day, the wooden wall gives a low variation of c...
Résumé – Cet article comporte deux parties, la première consiste à dimensionner, réaliser et expé... more Résumé – Cet article comporte deux parties, la première consiste à dimensionner, réaliser et expérimenter une installation de chauffage d’eau collectif d'une capacité de 400 litres. La deuxième partie est consacrée à l'étude du système d'appoint et l'influence du coût de cette énergie sur l'optimisation et le dimensionnement de l'installation. Abstract – This article includes two parts, the first one consists of the dimensioning, realisation and experimentation of a collective solar water heating installation having capacity of a 400 litres. The second part concerns the study of the auxiliary system and the cost influence of this energy on the installation optimisation and dimensioning.
The purpose of a bioclimatic house is to make every effort to reduce the need for heating and coo... more The purpose of a bioclimatic house is to make every effort to reduce the need for heating and cooling. For this a well studied architecture of the house is essential: - the positioning of windows to capture the maximum solar radiation, - Good thermal insulation of the house to reduce heat loss. This study focuses on the effect of solar and internal heat gain on the energy consumption of a typical well insulated house. The degree day's method is used to determine the heat losses by transmission and ventilation according to international standards on thermal insulation of building (NBN B62-301), the results are very interesting and promising. By including the solar and internal gains, which vary from 900 to 1400 kWh, the energy consumption decreases significantly. The thermal load for heat reaches 60 kWh, but by including the free thermal gains, 10 kWh of energy can be saved daily. Resume - L'objectif d'une maison bioclimatique est de tout mettre en œuvre pour reduire les ...
The purpose of this work concerns the study of the insulation effect upon the thermal behavior of... more The purpose of this work concerns the study of the insulation effect upon the thermal behavior of a house built with local materials according to Algerian building standard. In this regard, some simulations have been performed using the energy simulation software package ‘TRNSYS 16’ with the numerical model type 56. Our project involves the introduction of insulating materials in a building, so as to improve the thermal comfort and reduce the consumed energy. Different solutions and variants were proposed, in order to make a relevant choice, ensuring the best thermal comfort of a house while being as less energy-greedy as possible.
Wind energy is an important part of renewable energy sources in many countries. In the last decad... more Wind energy is an important part of renewable energy sources in many countries. In the last decades, the flow simulation for wind turbines have been studied more because it is a very good alternative for producing energy. The community of researches is normally focused on studying behavior and performance of wind farms, spectral contents of the power fluctuations, different methods of quantifying effects of turbulence-generated loads on wind turbine blade, influence of atmospheric turbulence on the fatigue loads. This paper is focused on turbulent flow modeling for 2 and 12 wind model turbines using Large-eddy simulation and Lagrangian-averaged scale-independent dynamic Smagorinsky model. Analyses of vortex behavior along turbine wake and analyses of normalized horizontal velocity profiles behind the wind turbine, as well as fractal dimension calculation for turbulent wake were performed using ImaCalc program. Normalized horizontal velocity profiles were compared with experimental r...
A significant portion of energy consumed in buildings is due to energy usage by heating, ventilat... more A significant portion of energy consumed in buildings is due to energy usage by heating, ventilation, and air conditioning (HVAC) systems. Free cooling is a good option for energy savings in (HVAC) systems. In recent years, scientists, engineers, and architects designed successful and innovative buildings which use passive cooling techniques, such as natural ventilation. The house studied in the present work, is a pilot project undertaken jointly by the Centre for Development of Renewable Energies (CDER) and the National Centre for Studies and Research of the integrated building (CNERIB) in the framework of the MED-ENEC project (Mediterranean Energy Efficiency in Construction structure). The house under consideration has a surface area of 65 m² and is located in the region of Algiers which characterized by a Mediterranean climate with relatively mild winters and a hot and humid summer. The aim of this work is to study the thermal comfort inside the house in summer without air condi...
The hygrothermal transfer is very important for the design of a building envelope for thermal com... more The hygrothermal transfer is very important for the design of a building envelope for thermal comfort and economic and energy analysis of the building envelope. The applications of various materials in building envelope have been studied extensively. The study presents several models for the hygrothermal transfer for various building walls. Several energy and mass conservation equations with different boundary conditions and input considerations were presented in this paper for concrete, bricks and wooden walls. The effect of hysteresis was ignored in developing most model equations, while few considered flow pattern of fluid through the wall surfaces. Due to the flexibility of Luikov models, it formed the basis for modelling the coupled heat and mass transfer for porous material independent of hygroscopic nature with different boundary conditions defined according to the geometry and orientations. The influence of type of wall, orientation, thickness, the density of the material an...
The passive solar house is designed to prevent heat loss and to maximize thermal input from the s... more The passive solar house is designed to prevent heat loss and to maximize thermal input from the sun. Our study focuses on the effect of solar and internal heat gain on energy consumption of a typical well insulated house. The degree day's method was used to determine the heat losses by transmission and ventilation according to international standards on thermal insulation of building (NBN B62-301). It was found that the results of the study are very interesting and promising. By including the solar and internal gains, varied from 900 to 1400 kWh, it was indicated that the energy consumption decreased significantly. The thermal load for heat reached 60 kWh, but by including the free thermal gains, 10 kWh of energy was saved per day.
The passive solar house is designed to prevent heat loss and to maximize thermal input from the s... more The passive solar house is designed to prevent heat loss and to maximize thermal input from the sun. Our study focuses on the effect of solar and internal heat gain on energy consumption of a typical well insulated house. The degree day's method was used to determine the heat losses by transmission and ventilation according to international standards on thermal insulation of building (NBN B62-301). It was found that the results of the study are very interesting and promising. By including the solar and internal gains, varied from 900 to 1400 kWh, it was indicated that the energy consumption decreased significantly. The thermal load for heat reached 60 kWh, but by including the free thermal gains, 10 kWh of energy was saved per day.
The building's form and thermal characteristics largely govern the amount of energy consumed by a... more The building's form and thermal characteristics largely govern the amount of energy consumed by a building. To avoid major flaws of the design, an architect needs to include the evaluation of the building's energy consumption in the earlier stages of the design process. If energy efficiency is not adequately considered during these stages, higher operating cost will accrue over the life of the building. In recent years, scientists, engineers and architects designed successful innovative buildings that use passive cooling techniques, such as natural ventilation. The house studied is a pilot project undertaken jointly by the Centre for Development of Renewable Energies (CDER) and the National Centre for Studies and Research of integrated building (CNERIB) under the MED-ENEC project (Mediterranean Energy Efficiency in Construction structure). The house subject of study is 65 m² surface area, located in the Algiers region characterized by a Mediterranean climate with relatively mild winters and hot, humid summer. This work is to study the comfort inside the house in the summer without air conditioning, ventilation only is considered. Numerical simulation is made under TRNSYS, the results compared with measured values are conclusive.
Tertiary habitat is the largest consumer of energy sector in Algeria. This corresponds to almost ... more Tertiary habitat is the largest consumer of energy sector in Algeria. This corresponds to almost 41% of national consumption. Final consumption in the residential sector reached 6 million tep in 2005. In this article, the results are analyzed after renovations made on a bungalow tourist complex located in Hammam Righa (100 km southwest of Algiers). The most important aspects for better energy performance of a building have been considered in this project. The calculations of thermal balances are made under the RETA software, according to the standards of the technical document DTR (C2-3), modeling the type of bungalow 5.5 using TRNSYS17 software. The results obtained show that after renovation of the bungalows, ambient temperatures are between 15 ° C and 20 ° C in winter and 25 ° C to 30 ° C in summer.
A significant portion of energy consumed in buildings is due to energy usage by heating, ventilat... more A significant portion of energy consumed in buildings is due to energy usage by heating, ventilation, and air conditioning systems. Free cooling is a good option for energy savings in the systems. In recent years, scientists, engineers, and architects designed successful and innovative buildings which use passive cooling techniques, such as natural ventilation. The house studied in the present work, is a pilot project undertaken jointly by the Centre for Development of Renewable Energies (CDER) and the National Centre for Studies and Research of the integrated building (CNERIB) in the framework of the MED-ENEC project (Mediterranean Energy Efficiency in Construction structure). The house under consideration has a surface area of 65 m2 and is located in the region of Algiers which characterized by a Mediterranean climate with relatively mild winters and a hot and humid summer. The aim of this work is to study the thermal comfort inside the house in summer without air conditioning sys...
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