M. Alaphilippe - Academia.edu (original) (raw)
Papers by M. Alaphilippe
International Journal of Thermodynamics, 2007
This paper considers thermodynamic conversion of solar energy into electric energy (up to maximum... more This paper considers thermodynamic conversion of solar energy into electric energy (up to maximum 50 kWe), presenting a very brief review of the possible systems: the ‘Dish/Stirling’ technology, which relies on high temperature Stirling engines and requires high solar energy; low temperature differential thermal engine using direct solar energy without any concentration but with very low power per unit volume or unit mass of the system; and the intermediate solar energy concentration ratio.A theoretical investigation on the coupling of a two-stage parabolic trough concentrator with a reciprocating Joule cycle air engine (i.e. an Ericsson hot air engine in open cycle) is presented. It is shown that there is an optimal operating point that maximises the mechanical power produced by the thermal engine. The interest of coupling a simple, low cost parabolic trough and a simple, low technology, mid-DT Ericsson engine is confirmed.
Cette communication étudie l’intérêt de systèmes hybrides de production d’énergie électrique de f... more Cette communication étudie l’intérêt de systèmes hybrides de production d’énergie électrique de faible puissance en site isolé, notamment pour des applications de télécommunication. L’élément principal de ces installations est un moteur thermique à apport de chaleur externe qui effectue la conversion de l’énergie solaire ou de la chaleur issue d'un combustible en électricité par voie thermodynamique. Nous évaluons les dimensions de différentes installations permettant de fournir 1 kWe en régime permanent, dans 5 localisations géographiques différentes.
International Journal of Thermal Sciences, 2005
Hot air engines (Stirling and Ericsson engines) are well suited for micro-cogeneration applicatio... more Hot air engines (Stirling and Ericsson engines) are well suited for micro-cogeneration applications because they are noiseless, and they require very low maintenance. Ericsson engines (i.e. Joule cycle reciprocating engines with external heat supply) are especially interesting because their design is less constrained than Stirling engines, leading to potentially cheaper and energetically better systems. We study the coupling of such an Ericsson engine with a system of natural gas combustion. In order to design this plant, we carry out classic energy, exergy and exergo-economic analyses. This study does not deal with a purely theoretical thermodynamic cycle. Instead, it is led with a special attempt to describe as accurately as possible what could be the design and the performance of a real engine. It allows us to balance energetic performance and heat exchanger sizes, to plot the exergy Grassmann diagram, and to evaluate the cost of the thermal and electric energy production. These simple analyses confirm the interest of such systems for micro-cogeneration purposes. The main result of this study is thus to draw the attention on Ericsson engines, unfortunately unfairly fallen into oblivion.
INTELEC 07 - 29th International Telecommunications Energy Conference, 2007
ABSTRACT This communication studies the interest of using hybrid systems to produce low power ele... more ABSTRACT This communication studies the interest of using hybrid systems to produce low power electrical energy on remote sites, e.g. for telecommunication applications. The main element of these installations is a thermal engine using external heat. The energy conversion into electricity is carried out by a thermodynamic process from solar energy or from fuel combustion. We assess the sizing of different installations designed for 1 permanent kWe, on 5 geographical localisations.
We present initially a summary recall of the state of the art of the systems of low or average po... more We present initially a summary recall of the state of the art of the systems of low or average power of conversion per thermodynamic way of solar energy into electric power. The current systems are primarily based on technology known as ' solar dish/Stirling', which uses Stirling engines at high temperature and thus requires a strong concentration of solar energy. These systems call upon a advanced and heavy technology, therefore expensive. With the other extreme, it is possible to produce mechanical energy by thermal engines at very low temperature, using the solar radiation not concentrated. We show, using a simple small size, that, because of the deterioration of the output of the solar collector with the temperature, the systems with very strong concentration present, from the energy point of view, a limited interest. An example of system without concentration shows that the latter are economically not very viable. The best way thus seems to be that of the systems with a...
Energy, 2014
ABSTRACT In this paper, a physical model is built to study the eutectic and progressive melting o... more ABSTRACT In this paper, a physical model is built to study the eutectic and progressive melting of salt solution in DSC (Differential Scanning Calorimetry) cells. The finite volume method is utilized to solve the heat transfer problem, and the general implicit source-based enthalpy method is employed to handle the absorbed latent heat during the phase change process. The resulting numerical solution is implicit in nature and although iteration on the time step is needed at each time level, the tridiagonal matrix algorithm can be utilized within the iterations leading to efficient and accurate solutions. The effects of the heating rate and the initial salt concentration on the kinetics of the melting process are examined.
INTELEC 07 - 29th International Telecommunications Energy Conference, 2007
ABSTRACT This communication studies the interest of using hybrid systems to produce low power ele... more ABSTRACT This communication studies the interest of using hybrid systems to produce low power electrical energy on remote sites, e.g. for telecommunication applications. The main element of these installations is a thermal engine using external heat. The energy conversion into electricity is carried out by a thermodynamic process from solar energy or from fuel combustion. We assess the sizing of different installations designed for 1 permanent kWe, on 5 geographical localisations.
This paper considers thermodynamic conversion of solar energy into electric energy (up to maximum... more This paper considers thermodynamic conversion of solar energy into electric energy (up to maximum 50 kWe), presenting a very brief review of the possible systems: the ‘Dish/Stirling’ technology, which relies on high temperature Stirling engines and requires high solar energy; low temperature differential thermal engine using direct solar energy without any concentration but with very low power per unit volume or unit mass of the system; and the intermediate solar energy concentration ratio.A theoretical investigation on the coupling of a two-stage parabolic trough concentrator with a reciprocating Joule cycle air engine (i.e. an Ericsson hot air engine in open cycle) is presented. It is shown that there is an optimal operating point that maximises the mechanical power produced by the thermal engine. The interest of coupling a simple, low cost parabolic trough and a simple, low technology, mid-DT Ericsson engine is confirmed.
Cette communication étudie l’intérêt de systèmes hybrides de production d’énergie électrique de f... more Cette communication étudie l’intérêt de systèmes hybrides de production d’énergie électrique de faible puissance en site isolé, notamment pour des applications de télécommunication. L’élément principal de ces installations est un moteur thermique à apport de chaleur externe qui effectue la conversion de l’énergie solaire ou de la chaleur issue d'un combustible en électricité par voie thermodynamique. Nous évaluons les dimensions de différentes installations permettant de fournir 1 kWe en régime permanent, dans 5 localisations géographiques différentes.
International Journal of Thermal Sciences, 2005
ABSTRACT Hot air engines (Stirling and Ericsson engines) are well suited for micro-cogeneration a... more ABSTRACT Hot air engines (Stirling and Ericsson engines) are well suited for micro-cogeneration applications because they are noiseless, and they require very low maintenance. Ericsson engines (i.e. Joule cycle reciprocating engines with external heat supply) are especially interesting because their design is less constrained than Stirling engines, leading to potentially cheaper and energetically better systems. We study the coupling of such an Ericsson engine with a system of natural gas combustion. In order to design this plant, we carry out classic energy, exergy and exergo-economic analyses. This study does not deal with a purely theoretical thermodynamic cycle. Instead, it is led with a special attempt to describe as accurately as possible what could be the design and the performance of a real engine. It allows us to balance energetic performance and heat exchanger sizes, to plot the exergy Grassmann diagram, and to evaluate the cost of the thermal and electric energy production. These simple analyses confirm the interest of such systems for micro-cogeneration purposes. The main result of this study is thus to draw the attention on Ericsson engines, unfortunately unfairly fallen into oblivion.
We present initially a summary recall of the state of the art of the systems of low or average po... more We present initially a summary recall of the state of the art of the systems of low or average power of conversion per thermodynamic way of solar energy into electric power. The current systems are primarily based on technology known as ' solar dish/Stirling', which uses Stirling engines at high temperature and thus requires a strong concentration of solar energy. These systems call upon a advanced and heavy technology, therefore expensive. With the other extreme, it is possible to produce mechanical energy by thermal engines at very low temperature, using the solar radiation not concentrated. We show, using a simple small size, that, because of the deterioration of the output of the solar collector with the temperature, the systems with very strong concentration present, from the energy point of view, a limited interest. An example of system without concentration shows that the latter are economically not very viable. The best way thus seems to be that of the systems with a...
International Journal of Thermodynamics, 2007
This paper considers thermodynamic conversion of solar energy into electric energy (up to maximum... more This paper considers thermodynamic conversion of solar energy into electric energy (up to maximum 50 kWe), presenting a very brief review of the possible systems: the ‘Dish/Stirling’ technology, which relies on high temperature Stirling engines and requires high solar energy; low temperature differential thermal engine using direct solar energy without any concentration but with very low power per unit volume or unit mass of the system; and the intermediate solar energy concentration ratio.A theoretical investigation on the coupling of a two-stage parabolic trough concentrator with a reciprocating Joule cycle air engine (i.e. an Ericsson hot air engine in open cycle) is presented. It is shown that there is an optimal operating point that maximises the mechanical power produced by the thermal engine. The interest of coupling a simple, low cost parabolic trough and a simple, low technology, mid-DT Ericsson engine is confirmed.
Cette communication étudie l’intérêt de systèmes hybrides de production d’énergie électrique de f... more Cette communication étudie l’intérêt de systèmes hybrides de production d’énergie électrique de faible puissance en site isolé, notamment pour des applications de télécommunication. L’élément principal de ces installations est un moteur thermique à apport de chaleur externe qui effectue la conversion de l’énergie solaire ou de la chaleur issue d'un combustible en électricité par voie thermodynamique. Nous évaluons les dimensions de différentes installations permettant de fournir 1 kWe en régime permanent, dans 5 localisations géographiques différentes.
International Journal of Thermal Sciences, 2005
Hot air engines (Stirling and Ericsson engines) are well suited for micro-cogeneration applicatio... more Hot air engines (Stirling and Ericsson engines) are well suited for micro-cogeneration applications because they are noiseless, and they require very low maintenance. Ericsson engines (i.e. Joule cycle reciprocating engines with external heat supply) are especially interesting because their design is less constrained than Stirling engines, leading to potentially cheaper and energetically better systems. We study the coupling of such an Ericsson engine with a system of natural gas combustion. In order to design this plant, we carry out classic energy, exergy and exergo-economic analyses. This study does not deal with a purely theoretical thermodynamic cycle. Instead, it is led with a special attempt to describe as accurately as possible what could be the design and the performance of a real engine. It allows us to balance energetic performance and heat exchanger sizes, to plot the exergy Grassmann diagram, and to evaluate the cost of the thermal and electric energy production. These simple analyses confirm the interest of such systems for micro-cogeneration purposes. The main result of this study is thus to draw the attention on Ericsson engines, unfortunately unfairly fallen into oblivion.
INTELEC 07 - 29th International Telecommunications Energy Conference, 2007
ABSTRACT This communication studies the interest of using hybrid systems to produce low power ele... more ABSTRACT This communication studies the interest of using hybrid systems to produce low power electrical energy on remote sites, e.g. for telecommunication applications. The main element of these installations is a thermal engine using external heat. The energy conversion into electricity is carried out by a thermodynamic process from solar energy or from fuel combustion. We assess the sizing of different installations designed for 1 permanent kWe, on 5 geographical localisations.
We present initially a summary recall of the state of the art of the systems of low or average po... more We present initially a summary recall of the state of the art of the systems of low or average power of conversion per thermodynamic way of solar energy into electric power. The current systems are primarily based on technology known as ' solar dish/Stirling', which uses Stirling engines at high temperature and thus requires a strong concentration of solar energy. These systems call upon a advanced and heavy technology, therefore expensive. With the other extreme, it is possible to produce mechanical energy by thermal engines at very low temperature, using the solar radiation not concentrated. We show, using a simple small size, that, because of the deterioration of the output of the solar collector with the temperature, the systems with very strong concentration present, from the energy point of view, a limited interest. An example of system without concentration shows that the latter are economically not very viable. The best way thus seems to be that of the systems with a...
Energy, 2014
ABSTRACT In this paper, a physical model is built to study the eutectic and progressive melting o... more ABSTRACT In this paper, a physical model is built to study the eutectic and progressive melting of salt solution in DSC (Differential Scanning Calorimetry) cells. The finite volume method is utilized to solve the heat transfer problem, and the general implicit source-based enthalpy method is employed to handle the absorbed latent heat during the phase change process. The resulting numerical solution is implicit in nature and although iteration on the time step is needed at each time level, the tridiagonal matrix algorithm can be utilized within the iterations leading to efficient and accurate solutions. The effects of the heating rate and the initial salt concentration on the kinetics of the melting process are examined.
INTELEC 07 - 29th International Telecommunications Energy Conference, 2007
ABSTRACT This communication studies the interest of using hybrid systems to produce low power ele... more ABSTRACT This communication studies the interest of using hybrid systems to produce low power electrical energy on remote sites, e.g. for telecommunication applications. The main element of these installations is a thermal engine using external heat. The energy conversion into electricity is carried out by a thermodynamic process from solar energy or from fuel combustion. We assess the sizing of different installations designed for 1 permanent kWe, on 5 geographical localisations.
This paper considers thermodynamic conversion of solar energy into electric energy (up to maximum... more This paper considers thermodynamic conversion of solar energy into electric energy (up to maximum 50 kWe), presenting a very brief review of the possible systems: the ‘Dish/Stirling’ technology, which relies on high temperature Stirling engines and requires high solar energy; low temperature differential thermal engine using direct solar energy without any concentration but with very low power per unit volume or unit mass of the system; and the intermediate solar energy concentration ratio.A theoretical investigation on the coupling of a two-stage parabolic trough concentrator with a reciprocating Joule cycle air engine (i.e. an Ericsson hot air engine in open cycle) is presented. It is shown that there is an optimal operating point that maximises the mechanical power produced by the thermal engine. The interest of coupling a simple, low cost parabolic trough and a simple, low technology, mid-DT Ericsson engine is confirmed.
Cette communication étudie l’intérêt de systèmes hybrides de production d’énergie électrique de f... more Cette communication étudie l’intérêt de systèmes hybrides de production d’énergie électrique de faible puissance en site isolé, notamment pour des applications de télécommunication. L’élément principal de ces installations est un moteur thermique à apport de chaleur externe qui effectue la conversion de l’énergie solaire ou de la chaleur issue d'un combustible en électricité par voie thermodynamique. Nous évaluons les dimensions de différentes installations permettant de fournir 1 kWe en régime permanent, dans 5 localisations géographiques différentes.
International Journal of Thermal Sciences, 2005
ABSTRACT Hot air engines (Stirling and Ericsson engines) are well suited for micro-cogeneration a... more ABSTRACT Hot air engines (Stirling and Ericsson engines) are well suited for micro-cogeneration applications because they are noiseless, and they require very low maintenance. Ericsson engines (i.e. Joule cycle reciprocating engines with external heat supply) are especially interesting because their design is less constrained than Stirling engines, leading to potentially cheaper and energetically better systems. We study the coupling of such an Ericsson engine with a system of natural gas combustion. In order to design this plant, we carry out classic energy, exergy and exergo-economic analyses. This study does not deal with a purely theoretical thermodynamic cycle. Instead, it is led with a special attempt to describe as accurately as possible what could be the design and the performance of a real engine. It allows us to balance energetic performance and heat exchanger sizes, to plot the exergy Grassmann diagram, and to evaluate the cost of the thermal and electric energy production. These simple analyses confirm the interest of such systems for micro-cogeneration purposes. The main result of this study is thus to draw the attention on Ericsson engines, unfortunately unfairly fallen into oblivion.
We present initially a summary recall of the state of the art of the systems of low or average po... more We present initially a summary recall of the state of the art of the systems of low or average power of conversion per thermodynamic way of solar energy into electric power. The current systems are primarily based on technology known as ' solar dish/Stirling', which uses Stirling engines at high temperature and thus requires a strong concentration of solar energy. These systems call upon a advanced and heavy technology, therefore expensive. With the other extreme, it is possible to produce mechanical energy by thermal engines at very low temperature, using the solar radiation not concentrated. We show, using a simple small size, that, because of the deterioration of the output of the solar collector with the temperature, the systems with very strong concentration present, from the energy point of view, a limited interest. An example of system without concentration shows that the latter are economically not very viable. The best way thus seems to be that of the systems with a...