References of "Declaye, Sébastien"
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See detailOrganic Rankine Cycles including fluid selection
Lemort, Vincent ULg; Declaye, Sébastien ULg; Quoilin, Sylvain ULg

in Handbook of Clean Energy Systems (in press)

An Organic Rankine Cycle (ORC) is similar to a steam Rankine cycle, except that the working fluid is not water but an organic compound, such as a refrigerant or a hydrocarbon, characterized by a lower ... [more ▼]

An Organic Rankine Cycle (ORC) is similar to a steam Rankine cycle, except that the working fluid is not water but an organic compound, such as a refrigerant or a hydrocarbon, characterized by a lower ebullition temperature than that of water. Hence lower temperature heat sources can be exploited such as solar energy, geothermal energy and waste heat recovery from many different processes. During the design phase of an ORC system, the selection of the working fluid must be conducted in parallel with the selection and the sizing of the components (mainly the expansion machine, the pump and the heat exchangers) and with the definition of the cycle architecture. This approach allows taking into consideration all technical constraints. Relevant properties of working fluids that should be considered during their selection are listed. Major characteristics of available displacement and turbo-expander technologies are described. The impact of the pump performance on the overall performance is discussed and strategies to increase the available NPSH are proposed. Finally, improved cycle architectures are introduced. Major applications of ORC systems are described: geothermal power plants, biomass CHP plants, waste heat recovery in industry, waste heat recovery on internal combustion engines and solar power plants. All these applications differ by the nature of the heat source and heat sink, the integration of the ORC with these sources and sinks, and the range of installed capacities. These differences yield specific designs, which are described. Performance achieved by systems in operation or prototypes are presented. [less ▲]

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See detailExperimental investigation of an ORC system for a micro-solar power plant
Dickes, Rémi ULg; Dumont, Olivier ULg; Declaye, Sébastien ULg et al

Conference (2014)

Because of the depletion of fossil fuels and global warming issues, the world energy sector is undergoing various changes towards increased sustainability. Among the different technologies being developed ... [more ▼]

Because of the depletion of fossil fuels and global warming issues, the world energy sector is undergoing various changes towards increased sustainability. Among the different technologies being developed, solar energy, and more specifically CSP (Concentrated Solar Power) systems are expected to play a key role to supply centralized loads and off-grid areas in the medium-term. Major performance improvements can be achieved by implementing advanced control strategies accounting for the transient and random nature of the solar heat source. In this context, a lab-scale solar power plant has been designed and is under construction for experimental purposes and dynamic analysis. The test rig includes an Organic Rankine Cycle (ORC) unit, a field of parabolic trough collectors and a thermal energy storage system. This paper presents the results of an experimental campaign conducted on the ORC module alone. This power unit, designed for a 2.8 kW net electrical output, consists of two scroll expanders in series, an air-cooled condenser, a recuperator, a volumetric pump and an oil-heated evaporator. The ORC engine is constructed using standard mass manufactured components from the HVAC industry, this practice reducing considerably the system cost. The overall unit performance and components effectiveness are presented in different operating conditions and relevant empirical correlations are derived to be implemented in a steady state model of the ORC unit. [less ▲]

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See detailSizing models and performance analysis of waste heat recovery organic Rankine cycles for heavy duty trucks
Guillaume, Ludovic ULg; Legros, Arnaud ULg; Quoilin, Sylvain ULg et al

in Proceedings of the ASME ORC 2013 second international seminar on ORC power systems (2013, October 07)

This paper attempts to address this problematic of selecting the architecture, the expander and the working fluid for a waste heat recovery organic (or non-organic) Rankine cycle on a truck engine. It ... [more ▼]

This paper attempts to address this problematic of selecting the architecture, the expander and the working fluid for a waste heat recovery organic (or non-organic) Rankine cycle on a truck engine. It focuses especially on three expander technologies: the scroll, the piston and the screw expanders, and three working fluids: R245fa, ethanol and water. [less ▲]

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See detailSizing models and performance analysis of volumetric expansion machines for waste heat recovery through organic Rankine cycles on passenger cars
Guillaume, Ludovic ULg; Legros, Arnaud ULg; Quoilin, Sylvain ULg et al

Scientific conference (2013, September 09)

This paper aims at helping designers of waste heat recovery organic (or non-organic) Rankine cycles on internal combustion engines to best select the expander among the piston, scroll and screw machines ... [more ▼]

This paper aims at helping designers of waste heat recovery organic (or non-organic) Rankine cycles on internal combustion engines to best select the expander among the piston, scroll and screw machines, and the working fluids among R245fa, ethanol and water. The first part of the paper presents the technical constraints inherent to each machine through a state of the art of the three technologies. The second part of the paper deals with the modeling of such expanders. Finally, in the last part of the paper, performances of the various Rankine systems are compared and a decision array is built to select the most appropriate couple of fluid and expander. [less ▲]

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See detailExperimental study on an open-drive scroll expander integrated into an ORC (Organic Rankine Cycle) system with R245fa as working fluid
Declaye, Sébastien ULg; Quoilin, Sylvain ULg; Guillaume, Ludovic ULg et al

in Energy (2013), 15

The present paper focuses on the experimental characterization of an open-drive scroll expander integrated into an Organic Rankine cycle using R245fa as working fluid. The expander is a commercially ... [more ▼]

The present paper focuses on the experimental characterization of an open-drive scroll expander integrated into an Organic Rankine cycle using R245fa as working fluid. The expander is a commercially available air compressor that was modified to operate in expander mode. The ORC (Organic Rankine Cycle) system is designed for a nominal heat input of 20 kW and a nominal net power output of 1.8 kW. A total of 74 steady-state operating points are measured to evaluate the expander performance over a wide range of conditions. The operating parameters that are varied include the inlet pressure (from 9 to 12 bar), outlet pressure (from 1.5 to 4 bar) and rotational speed (from 2000 to 3500 rpm). The maximum isentropic efficiency and shaft power are, respectively, 75.7% and 2.1 kW. A maximum cycle efficiency of 8.5% is reached for evaporating and condensing temperatures of 97.5 °C and 26.6 °C respectively. For most of the tests, hot water is produced in the condenser and the system therefore behaves as a CHP (combined heat and power). Depending on the water temperature requirement, a power to heat ratio varying between 1.9% and 11.8% is obtained. Water over 50 °C can be produced with a power to heat ratio higher than 8%. The experimental data points are then used to generate a performance map of the expander. This performance map allows for simulation of the use of such an expander in other ORC system [less ▲]

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See detailTechno-economic survey of Organic Rankine Cycle (ORC) systems
Quoilin, Sylvain ULg; van den Broeck, Martijn; Declaye, Sébastien ULg et al

in Renewable & Sustainable Energy Reviews (2013), 22

New heat conversion technologies need to be developed and improved to take advantage of the necessary increase in the supply of renewable energy. The Organic Rankine Cycle is well suited for these ... [more ▼]

New heat conversion technologies need to be developed and improved to take advantage of the necessary increase in the supply of renewable energy. The Organic Rankine Cycle is well suited for these applications, mainly because of its ability to recover low-grade heat and the possibility to be implemented in decentralized lower-capacity power plants. In This paper, an overview of the different ORC applications is presented. A market review is proposed including cost figures for several commercial ORC modules and manufacturers. An in-depth analysis of the technical challenges related to the technology, such as working fluid selection and expansion machine issues is then reported. Technological constraints and optimization methods are extensively described and discussed. Finally, the current trends in research and development for the next generation of Organic Rankine Cycles are presented. [less ▲]

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See detailDesign of a small-scale organic Rankine cycle engine used in a solar power plant
Georges, Emeline ULg; Declaye, Sébastien ULg; Dumont, Olivier ULg et al

in International Journal of Low Carbon Technologies (2013)

Under the economic and political pressure due to the depletion of fossil fuels and global warming concerns, it is necessary to develop more sustainable techniques to provide electrical power. In this ... [more ▼]

Under the economic and political pressure due to the depletion of fossil fuels and global warming concerns, it is necessary to develop more sustainable techniques to provide electrical power. In this context, the present study aims at designing, building and testing a small-scale organic Rankine cycle (ORC) solar power plant ( 3 kWe) in order to define and optimize control strategies that could be applied to larger systems. This paper presents a first step of the design of the solar power plant and focuses more specifically on the ORC engine. This design is defined on the basis of simulation models of the ORC engine and takes into account some technical limitations such as the allowed operating ranges and the technical maturity of the components. The final configuration includes a diaphragm pump, two plate heat exchangers for the regenerator and the evaporator, an air-cooled condenser, two hermetic scroll expanders in series and R245fa as the working fluid. Simulations indicate that an efficiency close to 12% for the ORC engine can be reached for evaporating and condensing temperatures of 140 and 358C, respectively. [less ▲]

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See detailA comparison of piston, screw and scroll expanders for small scale Rankine cycle systems
Lemort, Vincent ULg; Guillaume, Ludovic ULg; Legros, Arnaud ULg et al

in Proceedings of the 3rd International Conference on Microgeneration and Related Technologies (2013, April)

This paper aims at helping the designer of micro-scale Rankine Cycle heat engines to best select the expander among piston, screw and scroll machines. The first part of the paper presents a state of the ... [more ▼]

This paper aims at helping the designer of micro-scale Rankine Cycle heat engines to best select the expander among piston, screw and scroll machines. The first part of the paper presents a state of the art of these three technologies of positive displacement machines. The technical constraints inherent to each machine (rotational speed, pressure ratios, maximum temperatures, volumetric expansion ratios, etc.) are listed and the performance mentioned in the open technical and scientific literature is presented. The second part of the paper deals with the modeling of such expanders. Different simulation models are proposed: black-box, grey-box and white-box models. These three categories of modeling are specifically adapted to different purposes: design of the expander, design of the micro-CHP system, and dynamic simulation/control of the CHP unit. The last part of the paper presents a graphical methodology of selection of expansion machines and working fluids based on operating maps. It is stressed that the selections of both the expansion machine and working fluid should be conducted simultaneously. [less ▲]

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See detailOrganic Rankine Cycle Systems: A Techno-Economic Overview
van den Broeck, Martijn; Quoilin, Sylvain ULg; Declaye, Sébastien ULg et al

in Proceedings of EMC 2013 (2013)

The potential of organic Rankine cycle (ORC) technology for waste heat recovery in industry is discussed. This survey includes a market overview, a discussion of the key differences with steam turbine ... [more ▼]

The potential of organic Rankine cycle (ORC) technology for waste heat recovery in industry is discussed. This survey includes a market overview, a discussion of the key differences with steam turbine technology, some main selection issues (components and working fluid) and an outlook on the future of the technology. [less ▲]

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See detailDESIGN OF A SMALL-SCALE ORGANIC RANKINE CYCLE ENGINE USED IN A SOLAR POWER PLANT
Declaye, Sébastien ULg; Georges, Emeline ULg; Bauduin, Maxime ULg et al

in Proceedings of Heat Powered Cycles Conference 2012 (2012, September)

Under the economical and political pressure due to the depletion of fossil fuel and global warming potential, it is necessary to develop more sustainable techniques to provide electrical power. In this ... [more ▼]

Under the economical and political pressure due to the depletion of fossil fuel and global warming potential, it is necessary to develop more sustainable techniques to provide electrical power. In this context, medium and large scale Organic Rankine Cycle solar power plants appear to be a promising solution because of their good efficiency, robustness and acceptable economical probability. However, only a few ORC solar power plants are in operation today, but technical literature indicate that several demonstration projects are under development. The spreading out of that technology requires, among others, a good knowledge of control strategies of the entire plant comprising the field of parabolic trough collectors, the ORC engine and thermal storage systems. The present project aims at designing, building and testing a small scale ORC solar power plant (a few kWe) in order to define and optimize control strategies that could be applied to larger systems. The paper presents the design step of the solar power plant, and more specifically the ORC engine. This design is defined based on simulation models of the ORC engine and on the experience gained in the Thermodynamics laboratory in the field of testing small-scale ORC systems. The design accounts for technical limitations such as allowed operating ranges and technical maturity of components. The paper first presents the architecture of the envisioned solar plant. The choice of the different technologies of components is justified. Simulation models of components (scroll expander, plate and fin-and-tubes heat exchangers, etc.) and of the whole system are then presented. Based on those models, parametric studies are conducted in order to optimize the sizing and the operating conditions of the system and to select the most appropriate working fluid. Also, the relevance of using two expanders in series is discussed and the control of the ORC engine is investigated. Simulations indicate that ORC engine efficiency close to 12% can be reached for evaporating and condensing temperatures of 140°C and 35°C. [less ▲]

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See detailExperimental Investigation on a Reversible Heat Pump for a Passenger Car
Lemort, Vincent ULg; Cuevas, Cristian; Declaye, Sébastien ULg

in Proceedings of the 21st International Compressor Conference, Purdue 2012 (2012, July)

This paper summarizes the first results of a research project dealing with the development of a reversible heat pump for a passenger car. Heat pump systems appear to be a more efficient alternative to ... [more ▼]

This paper summarizes the first results of a research project dealing with the development of a reversible heat pump for a passenger car. Heat pump systems appear to be a more efficient alternative to electrical resistance heaters for the purpose of heating the car indoor environment. Heat pump systems could be easily implemented into cars by allowing the air-conditioning system to run in reverse. In order to check the technical feasibility of a reversible heat pump system, and to point out technical barriers, a prototype was built and tested. Experimental data was also used to calibrate and validate simulation models of components. A heat pump system model was finally built to investigate the operating conditions of the system. The first part of the paper describes the test rig (architecture, components, and measurement devices) and the experimental campaign. Performance of components (compressor, evaporator, condenser and heater core) is evaluated in terms of variation with the operating conditions. The second part of the paper presents the steady-state semi-empirical models of the components. Such lumped models retain and concentrate the main physical phenomena inherent to the components into successive elementary processes (pressure losses, heat transfers, etc.). They require a limited number of parameters that can be identified based on experimental data. The calibration and the validation of the proposed component models are detailed. Finally, an overall simulation model of the reversible heat pump system is proposed and used to evaluate the energy performance of the system as function of the operating conditions. [less ▲]

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See detailWorking fluid selection and operating maps for Organic Rankine Cycle expansion machines
Quoilin, Sylvain ULg; Declaye, Sébastien ULg; Legros, Arnaud ULg et al

in Proceedings of the 21st International Compressor Conference at Purdue (2012)

Fluid selection for the Organic Rankine Cycle has been the object of an abundant literature. Most of the scientific publications focus on the cycle thermodynamic efficiency in order to select the best ... [more ▼]

Fluid selection for the Organic Rankine Cycle has been the object of an abundant literature. Most of the scientific publications focus on the cycle thermodynamic efficiency in order to select the best candidate. However, other thermodynamics properties, such as molar mass, or vapor density condition the whole design of the cycle, and its cost. For example, the molar mass influences the number of stages required in the case of an axial turbine; the volume ratio between expander supply and exhaust conditions the possibility to use a volumetric expander (whose internal volume ratio is limited); the vapor density at the expander exhaust determine the size of the expander, and of the condenser; etc. This paper considers a whole range of ORC applications, in terms of power (from the kW-scale to the multi-MW plants), heat source temperature (from 90°C to more than 300°C) or heat source nature (solar, biomass, waste heat recovery, geothermy, etc.). For each of these applications, a screening of the available fluids is performed, and their thermodynamics performance are compared with respect to the foreseen application. A detailed analysis of the most common expansion machines is then conducted, by comparing their respective operating maps for each fluid and for each application type. The considered expansion machines are the radial-inflow turbine, the screw expander, and the scroll expander, since they are the most widely used in commercial applications and/or in scientific literature. [less ▲]

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See detailDevelopment of a waste heat recovery orc prototype using an oil-free scroll expander
Declaye, Sébastien ULg; Quoilin, Sylvain ULg; Lemort, Vincent ULg

Conference (2011, September 22)

The world is facing a historical increase in energy demand and energy consumption. As consequence the conventional fossil fuels are depleting faster with an inherent pollution causing severe damages to ... [more ▼]

The world is facing a historical increase in energy demand and energy consumption. As consequence the conventional fossil fuels are depleting faster with an inherent pollution causing severe damages to our environment. Renewable energy sources are considered as a solution to both environmental issue and energy demand. At the same time a lot of waste heat is witnessed in processes in industries. Our objective is to contribute to the development of ORC systems, that appear to us as a good solution to recover this wasted heat. In such waste heat applications, depending on the heat source flow rate and temperature, electrical power output can be as low as a few kilowatts. In this power range, there is no cost effective expansion machine available on the market. On existing prototypes, expansion devices are usually retrofitted volumetric compressors originally designed for refrigeration or air compression applications. Air compressors have the advantage to handle higher inlet temperature but tightness is often an issue in ORC application since the fluids used have a non negligible environmental impact. This paper presents the development of a small-scale WHR ORC unit at the Thermodynamic Laboratory of the University of Liège: the prototype uses a scroll expander, plate heat exchangers, a diaphragm piston pump and a liquid receiver. This system was tested with different working fluids (R123, R245fa and HFE7000) and a thermal efficiency close to 8% was obtained for a net output power of about 2 kWe. The specificity of the proposed prototype is the absence of lubrication: in order to avoid oil circulation in the ORC loop, an oil-free scroll expander is developed. This expander is originally an air scroll compressor that was modified using a magnetic coupling to ensure tightness. The experimental results highlight the good efficiency of the device, despite a relatively high internal leakage due to absence of lubrication. The necessity of using magnetic coupling is also justified by comparing the experimental results with previous ones obtained using mechanical sealing. [less ▲]

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See detailNumerical optimization of an injection volumetric expander for use in waste heat recovery organic Rankine cycle
Declaye, Sébastien ULg; Quoilin, Sylvain ULg; Lemort, Vincent ULg

in Proceedings of the 7th International Conference on Compressors and their Systems (2011, September 05)

Waste heat recovery organic Rankine cycle (ORC) systems allow generating mechanical or electrical power from local low grade heat sources. This paper shows how the power produced by the system can be ... [more ▼]

Waste heat recovery organic Rankine cycle (ORC) systems allow generating mechanical or electrical power from local low grade heat sources. This paper shows how the power produced by the system can be increased by achieving several evaporating pressure levels and injecting low pressure flow during expansion. A numerical model of the vapour injection expansion is developed and different system configurations are compared. In comparison with a simple configuration of the cycle, vapour injection configuration yields a maximum increase of 16% of the power production. Moreover, the specific power can be increased by 26%, which would largely reduce the specific investment cost of the waste heat recovery system. [less ▲]

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See detailExperimental characterization of a hermetic scroll expander for use in a micro-scale Rankine cycle
Lemort, Vincent ULg; Declaye, Sébastien ULg; Quoilin, Sylvain ULg

in Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy (2011)

This paper presents the results of an experimental study carried out on a prototype of a hermetic scroll expander, integrated into a gas cycle test rig, whose working fluid is HFC-245fa. This system was ... [more ▼]

This paper presents the results of an experimental study carried out on a prototype of a hermetic scroll expander, integrated into a gas cycle test rig, whose working fluid is HFC-245fa. This system was designed to test only the performance of the expander. It is mainly made up of a scroll compressor, a scroll expander, a heat exchanger and a by-pass valve. The latter is used to adjust the pressure ratio imposed to the expander. The expander is originally a compressor designed for heat pump applications and characterized by a nominal power input of 2.5 kWe. Performance of the expander is evaluated in terms of isentropic effectiveness and filling factor as function of the main operating conditions. The study also investigates the impact of oil mass fraction on the expander performance. Maximum overall isentropic effectiveness of 71.03% is measured, which is partly explained by the good volumetric performance of the machine. Using the experimental data, parameters of a semi-empirical simulation model of the expander are identified. This model is used to analyze the measured performance of the expander. Finally, a polynomial empirical model of the expander is proposed for fast and robust simulations of ORC systems. [less ▲]

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See detailThermo-Economic optimization of waste heat recovery Organic Rankine Cycles
Quoilin, Sylvain ULg; Declaye, Sébastien ULg; Tchanche, Bertrand F. et al

in Applied Thermal Engineering (2011)

The present paper focuses both on the thermodynamic and on the economic optimization of a small scale ORC in waste heat recovery application. A sizing model of the ORC is proposed, capable of predicting ... [more ▼]

The present paper focuses both on the thermodynamic and on the economic optimization of a small scale ORC in waste heat recovery application. A sizing model of the ORC is proposed, capable of predicting the cycle performance with different working fluids and different components sizes. The working fluids considered are R245fa, R123, n-butane, n-pentane and R1234yf and Solkatherm. Results indicate that, for the same fluid, the objective functions (economics profitability, thermodynamic efficiency) lead to different optimal working conditions in terms of evaporating temperature: the operating point for maximum power doesn’t correspond to that of the minimum specific investment cost: The economical optimum is obtained for n-butane with a specific cost of 2136 €/kW, a net output power of 4.2 kW, and an overall efficiency of 4.47%, while the thermodynamic optimum is obtained for the same fluid with an overall efficiency of 5.22%. It is also noted that the two optimizations can even lead to the selection of a different working fluid. This is mainly due to additional fluid properties that are not taken into account in the thermodynamic optimization, such as the fluid density: a lower density leads to the selection of bigger components which increases the cost and decreases the economical profitability. [less ▲]

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See detailEconomic feasibility study of a small scale Organic Rankine Cycle system in waste heat recovery applications
Tchanche, Bertrand; Quoilin, Sylvain ULg; Declaye, Sébastien ULg et al

(2010, August)

The Organic Rankine Cycle (ORC) appears progressively as a promising solution to recover waste heat energy from thermal processes for electricity generation. A prototype of small-scale ORC has been built ... [more ▼]

The Organic Rankine Cycle (ORC) appears progressively as a promising solution to recover waste heat energy from thermal processes for electricity generation. A prototype of small-scale ORC has been built and successfully tested at the University of Liège. It uses R-245fa and R-123 as working fluid, and an oil-free scroll compressor adapted to run in expander mode. Thermodynamic model of the system was derived and validated for performance prediction. The validated thermodynamic model is used to optimize the operation of the small ORC in waste heat recovery application (ORC-WHR). For exhaust gases at 180 ºC and a mass flow rate of 0.21 kg/s, a maximum net power output of 2 kWe is obtained for an evaporator pressure of 11.84 bar. The cycle thermal efficiency is 8.23 and the recuperation efficiency, 66.32%. Based on the aforementioned conditions, the economic assessment of small scale ORC-WHR was carried out using economic criteria such as levelized electricity cost (LEC), Net present value (NPV) and depreciated payback period (DPP). For a 2kWe ORC-WHR, the specific installed cost is 5775 €/kW with a LEC of 13.27 c€/kWh while for a 50 kWe, the specific installed cost is about 3034 €/kW and the LEC, 7c€/kWh. For an electricity unit price of 20 c€/kWh, the payback period of a 2 kWe system is 6 years while it is 2.5 years for a 50 kWe system. It is concluded from the study that recovering the waste heat by way of ORCs is technically and economically feasible. As recycled energy, waste heat has the same advantages as renewable energy and should benefit from the same legislative conditions (Feed-in-Laws). [less ▲]

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See detailDesign and Experimental investigation of a Small scale organic Rankine using a scroll expander
Declaye, Sébastien ULg; Quoilin, Sylvain ULg; Lemort, Vincent ULg

in Proceeding of the 13th International Refrigeration and Air Conditioning Conference at Purdue (2010, July 11)

The world is facing a historical increase in energy demand and energy consumption. As consequence the conventional fossil fuels are depleting faster with an inherent pollution causing sever damages to our ... [more ▼]

The world is facing a historical increase in energy demand and energy consumption. As consequence the conventional fossil fuels are depleting faster with an inherent pollution causing sever damages to our environment. Renewable energy sources are considered as a solution to both environmental issue and energy demand. At the same time a lot of waste heat is witnessed in processes in industries and other thermal devices such internal combustion engines. Our objective is to propose a solution to recover this heat wasted. The organic Rankine cycle appeared to us as a solution. This paper presents a study carried out on a prototype of small scale organic Rankine cycle (ORC) driven by two waste heat hot air streams. The prototype was designed using a diaphragm pump, a set of plate heat exchangers and an oil-free scroll compressor adapted to run in expander mode. The available literature on Organic Rankine Cycles only proposes theoretical studies of fluid selection for a given application. This study aims at comparing fluids experimentally. Therefore, several fluids (including R245fa and R123) were tested in the prototype and the performance was measured. The tests were performed to study the performance of the ORC system and the expander over a wide range of working conditions. The temperature of the heat sources varied between 150°C and 200°C. The maximum expander shaft power was above 2kW and maximum expander efficiency was 70%. These tests allowed to point out the critical characteristics that should be taken into account while selecting the components for the design of an ORC. [less ▲]

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See detailExpansion Machine and fluid selection for the Organic Rankine Cycle
Quoilin, Sylvain ULg; Declaye, Sébastien ULg; Lemort, Vincent ULg

in Proceedings of the 7th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics (2010, July)

This paper considers a whole range of ORC applications, in terms of power (from the kW-scale to the multi-MW plants), heat source temperature (from 90°C to more than 300°C) or heat source nature (solar ... [more ▼]

This paper considers a whole range of ORC applications, in terms of power (from the kW-scale to the multi-MW plants), heat source temperature (from 90°C to more than 300°C) or heat source nature (solar, biomass, waste heat recovery, geothermy, etc.). Five typical ORC applications are considered in terms of evaporating and condensing temperature. A screening of the most used ORC working fluids is performed, and their thermodynamics performances are compared with respect to the foreseen application. A detailed analysis of the most common expansion machines is then conducted, by comparing their respective operating maps for each fluid and for each application type. The considered expansion machines are the single-stage radial-inflow turbine, the screw expander, and the scroll expander, which are widely used in commercial applications and/or in scientific literature. The limitations of these machines are listed and considered to define an operating map for each considered fluid. Finally, the allowable power range is described with respect to the application and to the selected expansion device. [less ▲]

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