The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Arturo De Risi - One of the best experts on this subject based on the ideXlab platform.
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experimental investigation of transparent Parabolic Trough Collector based on gas phase nanofluid
Applied Energy, 2017Co-Authors: Marco Potenza, Marco Milanese, Gianpiero Colangelo, Arturo De RisiAbstract:Abstract An experimental study on new high temperature Parabolic Trough Collector (PTC), with transparent receiver tube, based on gas-phase nanofluid, has been carried out for the first time in this work. Two-axes solar tracking PTC, with 4 m 2 reflecting surface has been realized. Besides, two coaxial quartz tubes, with vacuum in the inner space were used as receiver pipe, with air-dispersed CuO nano-powders as working fluid. The aim of this work was to investigate the technological issues related to the use of gas-based nanofluid coupled with transparent quartz receiver and to evaluate the performance of the first prototype, comparing numerical and experimental results. The experimental campaign highlighted a critical issue related to nanopowder deposition within the receiver pipe, due to humidity. Moreover, in a day of measurement, the fluid temperature higher than 145 °C has been maintained for about 10 h, reaching a maximum value of 180 °C, with a mean efficiency of about 65%.
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modelling and optimization of transparent Parabolic Trough Collector based on gas phase nanofluids
Renewable Energy, 2013Co-Authors: Arturo De Risi, Marco Milanese, Domenico LaforgiaAbstract:Abstract The Parabolic Trough Collector (PTC) is the most common type of high-temperature solar thermal technology, in which the heat transfer fluid is usually synthetic oil, molten salt or water/steam. Experiences in existing plants have shown some operating problems with all these types of fluid, which limit solar to thermal efficiency and increase power plant costs. To solve such constraints an innovative solar Transparent Parabolic Through Collector (TPTC) working with gas-based nanofluid has been proposed and investigated in the present paper. Transparent receivers combined with gas-based nanofluids were found to be able to directly adsorb solar radiation due to the very high total surface of nanoparticles. The use of directly radiated nanoparticles allows compensating the relatively low heat transfer coefficient typical of gaseous heat transfer fluids with an increase of the exchange surface. Yet to allow a complete absorption of the solar energy within the transparent receiver tube a proper mixture of CuO and Ni nanoparticles has been designed. The proposed solar Collector has been modelled by means of a discretized in space model to simplify the description of the behaviour of the physical system under the assumptions of quasi steady state conditions. The above-mentioned model has then been used to run an optimization procedure to define the main geometrical and operational parameters of the TPTC. Simulations have shown that the maximum TPTC solar to thermal efficiency is 62.5%, for a nanofluid outlet temperature of 650 °C and a nanoparticles volume concentration of 0.3%.
Dominique Rochier - One of the best experts on this subject based on the ideXlab platform.
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experimental study of a micro combined heat and power system with a solar Parabolic Trough Collector coupled to a steam rankine cycle expander
Solar Energy, 2016Co-Authors: Jeanlouis Bouvier, Ghislain Michaux, Patrick Salagnac, Thiebaut Kientz, Dominique RochierAbstract:Abstract Micro Combined Heat and Power (micro-CHP) devices are seen as promising solutions for the reduction of fossil fuel consumption and CO2 emissions in the building sector. A micro-CHP system composed of a solar Parabolic Trough Collector in direct steam generation coupled to a steam Rankine cycle expander has been developed and studied. The presented results show the feasibility of coupling a solar Collector in direct steam generation to an expander for micro-CHP purposes. However, the dynamic tests point out important fluctuations of the expander inlet conditions due to the relatively high volume of the solar Collector with respect to the flow rate. In order to limit these fluctuations, a PI controller has been implemented to control the expander inlet pressure. Two steady state points have been obtained. The reached electrical power output is relatively low (around 1.3 kW) and leads to a solar-to-electricity efficiency close to 3%. The solar-to-thermal efficiency is close to 38% for a thermal power output of 19 kW. These limited values are due to the low operating pressure (maximum 26.3 bar), to the high heat losses and to the efficiency of the solar Collector. The temperature of the building supply water was measured around 60 °C and values above 80 °C can be reached, which is sufficient for hot water production or heating.
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experimental characterisation of a solar Parabolic Trough Collector used in a micro chp micro cogeneration system with direct steam generation
Energy, 2015Co-Authors: Jeanlouis Bouvier, Ghislain Michaux, Patrick Salagnac, Francois Nepveu, Dominique Rochier, Thiebaut KientzAbstract:An experimental campaign has been conducted on a solar Parabolic Trough Collector feeding a micro-CHP system (micro-cogeneration). The originality of the solar field is the DSG (direct steam generation) using a two axis tracker and a small size (46.5 m2) Collector. The first step of the characterisation of the CHP (Combined Heat and Power) system is the study of the solar field under direct steam generation.
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Experimental characterisation of a solar Parabolic Trough Collector used in a micro-CHP (micro-cogeneration) system with direct steam generation
Energy, 2015Co-Authors: Jeanlouis Bouvier, Ghislain Michaux, Patrick Salagnac, Francois Nepveu, Dominique Rochier, Thiebaut KientzAbstract:Abstract An experimental campaign has been conducted on a solar Parabolic Trough Collector feeding a micro-CHP system (micro-cogeneration). The originality of the solar field is the DSG (direct steam generation) using a two axis tracker and a small size (46.5 m 2 ) Collector. The first step of the characterisation of the CHP (Combined Heat and Power) system is the study of the solar field under direct steam generation. Thermal performances under sunny and cloudy conditions are presented. On the studied sunny day, the system produces saturated steam during 8 h with a quality higher than 0.6 for a flow rate of 33 kg/h. Thanks to the two axis tracker, the output power and steam production are stable throughout the day. The dynamics of the Collectors observed on a cloudy day under two-phase flow, show strong variations of the output power and flow rate that can even cease with clouds. Next, the impact of working and outdoor conditions is presented. Finally, the thermal efficiency of the Collector is measured with steam. Reached efficiency is consistent with the literature for small size systems with direct steam generation. The Collector performances are suitable for the coupling with the steam engine. Thus, the first results obtained with the engine are presented.
Nishith B Desai - One of the best experts on this subject based on the ideXlab platform.
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thermo economic analysis and selection of working fluid for solar organic rankine cycle
Applied Thermal Engineering, 2016Co-Authors: Nishith B DesaiAbstract:Abstract Organic Rankine cycle (ORC), powered by line-focusing concentrating solar Collectors (Parabolic Trough Collector and linear Fresnel reflector), is a promising option for modular scale. ORC based power block, with dry working fluids, offers higher design and part-load efficiencies compared to steam Rankine cycle (SRC) in small-medium scale, with temperature sources up to 400 °C. However, the cost of ORC power block is higher compared to the SRC power block. Similarly, Parabolic Trough Collector (PTC) system has higher optical efficiency and higher cost compared to linear Fresnel reflector (LFR) system. The thermodynamic efficiencies and power block costs also vary with working fluids of the Rankine cycle. In this paper, thermo-economic comparisons of organic Rankine and steam Rankine cycles powered by line-focusing concentrating solar Collectors are reported. A simple selection methodology, based on thermo-economic analysis, and a comparison diagram for working fluids of power generating cycles are also proposed. Concentrating solar power plants with any Collector technology and any power generating cycle can be compared using the proposed methodology.
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optimization of concentrating solar thermal power plant based on Parabolic Trough Collector
Journal of Cleaner Production, 2015Co-Authors: Nishith B Desai, Santanu BandyopadhyayAbstract:Abstract Concentrating solar power (CSP) plant with Parabolic Trough Collector (PTC) using synthetic or organic oil based heat transfer fluid is the most established and commercially attractive technology. In this paper, extensive energy and economic analysis of PTC based CSP plants, without storage, are reported. Effects of turbine inlet pressure, turbine inlet temperature, design radiation, plant size, and various modifications of Rankine cycle on overall efficiency as well as levelized cost of energy are studied. Furthermore, the variation in optimal turbine inlet pressure with turbine inlet temperature, design radiation, plant size, and various modifications of Rankine cycle are also analyzed. Energy and cost optimal turbine inlet pressures for 1 MWe plant (with basic Rankine cycle) are about 4.5–7.5 MPa and 3.5–7.5 MPa, respectively. The optimum pressure is observed to be a weak function of design solar radiation. The overall efficiency increases and levelized cost of energy decreases with increase in turbine inlet temperature, plant size and various modifications of the Rankine cycle.
Jeanlouis Bouvier - One of the best experts on this subject based on the ideXlab platform.
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experimental study of a micro combined heat and power system with a solar Parabolic Trough Collector coupled to a steam rankine cycle expander
Solar Energy, 2016Co-Authors: Jeanlouis Bouvier, Ghislain Michaux, Patrick Salagnac, Thiebaut Kientz, Dominique RochierAbstract:Abstract Micro Combined Heat and Power (micro-CHP) devices are seen as promising solutions for the reduction of fossil fuel consumption and CO2 emissions in the building sector. A micro-CHP system composed of a solar Parabolic Trough Collector in direct steam generation coupled to a steam Rankine cycle expander has been developed and studied. The presented results show the feasibility of coupling a solar Collector in direct steam generation to an expander for micro-CHP purposes. However, the dynamic tests point out important fluctuations of the expander inlet conditions due to the relatively high volume of the solar Collector with respect to the flow rate. In order to limit these fluctuations, a PI controller has been implemented to control the expander inlet pressure. Two steady state points have been obtained. The reached electrical power output is relatively low (around 1.3 kW) and leads to a solar-to-electricity efficiency close to 3%. The solar-to-thermal efficiency is close to 38% for a thermal power output of 19 kW. These limited values are due to the low operating pressure (maximum 26.3 bar), to the high heat losses and to the efficiency of the solar Collector. The temperature of the building supply water was measured around 60 °C and values above 80 °C can be reached, which is sufficient for hot water production or heating.
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experimental characterisation of a solar Parabolic Trough Collector used in a micro chp micro cogeneration system with direct steam generation
Energy, 2015Co-Authors: Jeanlouis Bouvier, Ghislain Michaux, Patrick Salagnac, Francois Nepveu, Dominique Rochier, Thiebaut KientzAbstract:An experimental campaign has been conducted on a solar Parabolic Trough Collector feeding a micro-CHP system (micro-cogeneration). The originality of the solar field is the DSG (direct steam generation) using a two axis tracker and a small size (46.5 m2) Collector. The first step of the characterisation of the CHP (Combined Heat and Power) system is the study of the solar field under direct steam generation.
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Experimental characterisation of a solar Parabolic Trough Collector used in a micro-CHP (micro-cogeneration) system with direct steam generation
Energy, 2015Co-Authors: Jeanlouis Bouvier, Ghislain Michaux, Patrick Salagnac, Francois Nepveu, Dominique Rochier, Thiebaut KientzAbstract:Abstract An experimental campaign has been conducted on a solar Parabolic Trough Collector feeding a micro-CHP system (micro-cogeneration). The originality of the solar field is the DSG (direct steam generation) using a two axis tracker and a small size (46.5 m 2 ) Collector. The first step of the characterisation of the CHP (Combined Heat and Power) system is the study of the solar field under direct steam generation. Thermal performances under sunny and cloudy conditions are presented. On the studied sunny day, the system produces saturated steam during 8 h with a quality higher than 0.6 for a flow rate of 33 kg/h. Thanks to the two axis tracker, the output power and steam production are stable throughout the day. The dynamics of the Collectors observed on a cloudy day under two-phase flow, show strong variations of the output power and flow rate that can even cease with clouds. Next, the impact of working and outdoor conditions is presented. Finally, the thermal efficiency of the Collector is measured with steam. Reached efficiency is consistent with the literature for small size systems with direct steam generation. The Collector performances are suitable for the coupling with the steam engine. Thus, the first results obtained with the engine are presented.
Thiebaut Kientz - One of the best experts on this subject based on the ideXlab platform.
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experimental study of a micro combined heat and power system with a solar Parabolic Trough Collector coupled to a steam rankine cycle expander
Solar Energy, 2016Co-Authors: Jeanlouis Bouvier, Ghislain Michaux, Patrick Salagnac, Thiebaut Kientz, Dominique RochierAbstract:Abstract Micro Combined Heat and Power (micro-CHP) devices are seen as promising solutions for the reduction of fossil fuel consumption and CO2 emissions in the building sector. A micro-CHP system composed of a solar Parabolic Trough Collector in direct steam generation coupled to a steam Rankine cycle expander has been developed and studied. The presented results show the feasibility of coupling a solar Collector in direct steam generation to an expander for micro-CHP purposes. However, the dynamic tests point out important fluctuations of the expander inlet conditions due to the relatively high volume of the solar Collector with respect to the flow rate. In order to limit these fluctuations, a PI controller has been implemented to control the expander inlet pressure. Two steady state points have been obtained. The reached electrical power output is relatively low (around 1.3 kW) and leads to a solar-to-electricity efficiency close to 3%. The solar-to-thermal efficiency is close to 38% for a thermal power output of 19 kW. These limited values are due to the low operating pressure (maximum 26.3 bar), to the high heat losses and to the efficiency of the solar Collector. The temperature of the building supply water was measured around 60 °C and values above 80 °C can be reached, which is sufficient for hot water production or heating.
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experimental characterisation of a solar Parabolic Trough Collector used in a micro chp micro cogeneration system with direct steam generation
Energy, 2015Co-Authors: Jeanlouis Bouvier, Ghislain Michaux, Patrick Salagnac, Francois Nepveu, Dominique Rochier, Thiebaut KientzAbstract:An experimental campaign has been conducted on a solar Parabolic Trough Collector feeding a micro-CHP system (micro-cogeneration). The originality of the solar field is the DSG (direct steam generation) using a two axis tracker and a small size (46.5 m2) Collector. The first step of the characterisation of the CHP (Combined Heat and Power) system is the study of the solar field under direct steam generation.
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Experimental characterisation of a solar Parabolic Trough Collector used in a micro-CHP (micro-cogeneration) system with direct steam generation
Energy, 2015Co-Authors: Jeanlouis Bouvier, Ghislain Michaux, Patrick Salagnac, Francois Nepveu, Dominique Rochier, Thiebaut KientzAbstract:Abstract An experimental campaign has been conducted on a solar Parabolic Trough Collector feeding a micro-CHP system (micro-cogeneration). The originality of the solar field is the DSG (direct steam generation) using a two axis tracker and a small size (46.5 m 2 ) Collector. The first step of the characterisation of the CHP (Combined Heat and Power) system is the study of the solar field under direct steam generation. Thermal performances under sunny and cloudy conditions are presented. On the studied sunny day, the system produces saturated steam during 8 h with a quality higher than 0.6 for a flow rate of 33 kg/h. Thanks to the two axis tracker, the output power and steam production are stable throughout the day. The dynamics of the Collectors observed on a cloudy day under two-phase flow, show strong variations of the output power and flow rate that can even cease with clouds. Next, the impact of working and outdoor conditions is presented. Finally, the thermal efficiency of the Collector is measured with steam. Reached efficiency is consistent with the literature for small size systems with direct steam generation. The Collector performances are suitable for the coupling with the steam engine. Thus, the first results obtained with the engine are presented.
