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Utveckling av dataanalysprogram för Opcon Powerbox / Development of data analysis software for Opcon PowerboxHolmgren, Magnus January 2010 (has links)
Opcon Powerbox is a product developed by Opcon together with the underlying company SRM (Svenska Rotor Maskiner) where surplus heat from the industry is used through an Organic Rankine Cycle (ORC)–process to produce electricity. An ORC-process is a thermodynamic circle process in which a refrigerant is used as the working fluid. The refrigerant makes it possible for the circle process to operate at lower temperatures than the conventional Rankine process. In this master’s thesis a data analysis software for the Opcon Powerbox has been developed in which measurement data is retrieved and handled from the Opcon Powerbox. The software performs calculations and analysis on the data with which the system can be evaluated. This thesis has been carried out with SRM.
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Exergoeconomic Analysis of Solar Organic Rankine Cycle for Geothermal Air Conditioned Net Zero Energy BuildingsRayegan, Rambod 12 July 2011 (has links)
This study is an attempt at achieving Net Zero Energy Building (NZEB) using a solar Organic Rankine Cycle (ORC) based on exergetic and economic measures. The working fluid, working conditions of the cycle, cycle configuration, and solar collector type are considered the optimization parameters for the solar ORC system.
In the first section, a procedure is developed to compare ORC working fluids based on their molecular components, temperature-entropy diagram and fluid effects on the thermal efficiency, net power generated, vapor expansion ratio, and exergy efficiency of the Rankine cycle. Fluids with the best cycle performance are recognized in two different temperature levels within two different categories of fluids: refrigerants and non-refrigerants. Important factors that could lead to irreversibility reduction of the solar ORC are also investigated in this study.
In the next section, the system requirements needed to maintain the electricity demand of a geothermal air-conditioned commercial building located in Pensacola of Florida is considered as the criteria to select the optimal components and optimal working condition of the system. The solar collector loop, building, and geothermal air conditioning system are modeled using TRNSYS. Available electricity bills of the building and the 3-week monitoring data on the performance of the geothermal system are employed to calibrate the simulation. The simulation is repeated for Miami and Houston in order to evaluate the effect of the different solar radiations on the system requirements.
The final section discusses the exergoeconomic analysis of the ORC system with the optimum performance. Exergoeconomics rests on the philosophy that exergy is the only rational basis for assigning monetary costs to a system’s interactions with its surroundings and to the sources of thermodynamic inefficiencies within it. Exergoeconomic analysis of the optimal ORC system shows that the ratio Rex of the annual exergy loss to the capital cost can be considered a key parameter in optimizing a solar ORC system from the thermodynamic and economic point of view. It also shows that there is a systematic correlation between the exergy loss and capital cost for the investigated solar ORC system.
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Implementation of an Organic Rankine cycle on a Stepping furnacePižorn, Žiga January 2014 (has links)
In this master thesis an implementation of an Organic Rankine Cycle (ORC) on a stepping furnace in a steel mill is modeled and proposed. The study is a case study at the company Štore&STEEL d.o.o. with intentions of realization. In a steel mill a stepping furnace is used to preheat the steel billets for later forging. The stepping furnace is gas fired and already has recuperation of the inlet air implemented. Still there is high temperature of the stack after recuperation, which makes application of an ORC worth of researching and modeling.First the flue gas over one year of furnace operation is analyzed in terms of temperature and volumetric flow. Mass flow and heat capacity are calculated. A layout of an ORC is proposed and modeled in IPSEpro for different temperatures of the flue gas resulting in different output powers and efficiencies. For each temperature an economic viability calculation with the method of reference cost of electric energy is done.The results are presented and the best design and conditions are proposed. The results of the thesis proved that further detailed measurements and calculation are worthwhile , as the flue gas from the stepping furnace has satisfactory conditions to make an application of an Organic Rankine cycle viable. Also the least ammount of state support to fulfill the companies conditions on return of investment is calculated and presented. Finally there are additional measurements and calculations suggested.
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Experimental investigation of scroll based organic Rankine systemsTarique, Md. Ali 01 April 2011 (has links)
In this thesis, an experimental research is conducted on scroll-based Organic Rankine Cycle (ORC) focusing on the expansion process. An important feature of the ORC is the ability to utilize low or moderate temperature heat sources derived from renewable energy such as concentrated solar radiation, biomass/biofuels combustion streams, geothermal heat and waste heat recovery. The ORC is more appropriate than steam Rankine cycle to generate power from low capacity heat sources (5-500 kW thermal). For example, expansion of superheated steam from 280oC/1000 kPa to a pressure corresponding to 35oC saturation requires a volume ratio as high as 86, whereas for the same operating conditions toluene shows an expansion ratio of 6 which can be achieved in a single stage turbine or expander.
The objective of this work is to experimentally study the performance of a selected refrigeration scroll compressor operating in reverse as expander in an ORC. To this purpose, three experimental systems are designed, built and used for conducting a comprehensive experimental programme aimed at determining the features of the expansion process. In preliminary tests the working fluid utilized is dry air while the main experiments are done with the organic fluid R134a.
Experimental data of the scroll expander are collected under different operating conditions. Power generation in various conditions is analyzed in order to determine the optimum performance parameters for the scroll expander. In addition, thermodynamic analysis of the system is conducted through energy and exergy efficiencies to study the system performance.
Based on the experimental measurements, the optimum parameters for an ORC cycle operating with the Bitzer-based expander-generator unit are determined. The cycle energy and exergy efficiencies are found 5% and 30% respectively from a heat source of 120oC. / UOIT
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Modeling And Performance Evaluation Of An Organic Rankine Cycle (orc) With R245fa As Working FluidBamgbopa, Musbaudeen Oladiran 01 July 2012 (has links) (PDF)
This thesis presents numerical modelling and analysis of a solar Organic Rankine Cycle
(ORC) for electricity generation. A regression based approach is used for the working fluid
property calculations. Models of the unit&rsquo / s sub-components (pump, evaporator, expander
and condenser) are also established. Steady and transient models are developed and
analyzed because the unit is considered to work with stable (i.e. solar + boiler) or variable
(i.e. solar only) heat input. The unit&rsquo / s heat exchangers (evaporator and condenser) have
been identified as critical for the applicable method of analysis (steady or transient). The
considered heat resource into the ORC is in the form of solar heated water, which varies
between 80-95 0C at a range of mass flow rates between 2-12 kg/s. Simulation results of
steady state operation using the developed model shows a maximum power output of
around 40 kW. In the defined operation range / refrigerant mass flow rate, hot water mass
flow rate and hot water temperature in the system are identified as critical parameters to
optimize the power production and the cycle efficiency. The potential benefit of controlling
these critical parameters is demonstrated for reliable ORC operation and optimum power
production. It is also seen that simulation of the unit&rsquo / s dynamics using the transient model is
imperative when variable heat input is involved, due to the fact that maximum energy
recovery is the aim with any given level of heat input.
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Heat waste recovery system from exhaust gas of diesel engine to a reciprocal steam engineDuong, Tai Anh 05 October 2011 (has links)
This research project was about the combined organic Rankine cycle which extracted energy from the exhaust gas of a diesel engine. There was a study about significant properties of suitable working fluids. The chosen working fluid, R134a, was used to operate at the dry condition when it exited the steam piston engine. Furthermore, R134a is environmentally friendly with low environmental impact. It was also compatible with sealing materials. There were calibrations for the components of the combined Rankine cycle. The efficiency of the heat exchanger converting exhaust heat from the diesel engine to vaporize R134a was 89%. The average efficiency of the generator was 50%. The hydraulic pump used for the combined Rankine cycle showed a transporting problem, as vapor-lock occurred when the pump ran for about 1 minute. The output of the combined Rankine cycle was normalized to compensate for the parasitic losses of a virtual vane pump used in hydraulic systems for the 6 liter diesel engines. There were three different vane pump widths from different pumps to compare frictional loss. The pump with the smallest vane width presented the least frictional mean effective pressure (fmep) (0.26 kPa) when scaled with the displacement of the GMC Sierra 6 liter diesel engine. The power output of the Rankine cycle was scaled to brake mean effective pressure (bmep) to compare with the frictional mean effective pressure. The maximum bmep was at 0.071 kPa when diesel engine had rotational speed at 2190 RPM. The power outputs of the organic Rankine compensated partially the frictional loss of the vane pumps in the 6 liter diesel engine. By using R134a, the condensing pressure was 0.8 MPa; hence, the power outputs from steam engine were limited. Therefore, refrigerants with lower condensing pressure were needed. There were proposal for improvement of the organic Rankine by substituting R134a by R123 (0.1 MPa), R21 (0.2 MPa), and R114 (0.25 MPa) . / text
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Development of a low temperature geothermal organic rankine cycle standard.Taylor, Leighton John January 2015 (has links)
The growth in renewable electricity generation is forecast to continue as fossil fuel levels decrease and carbon dioxide emissions are penalized. The growth in geothermal is becoming constrained as conventional high-temperature sources are fully exploited. Geothermal can be a cost competitive base load power source. Governments and utilities are looking at the potential of electricity generation from low temperature geothermal resources for future development. This technology, unlike the high and medium temperature, is not mature and there are a number of companies looking at entering the Organic Rankine Cycle (ORC) market.
This thesis aims to provide a necessary step for reliable commercial develop this technology by developing the first draft of a low temperature geothermal ORC standard. The standard outlines the
critical stages of a geothermal ORC project as the Prospecting stage; Pre-Feasibility stage, Feasibility stage, and the Detailed Design stage. The standard is unlike other standards that are used to design one
component; this standard guides the engineers though the various critical steps of the ORC design to correctly assess the geothermal resource and to inform design and investment decisions.
The standard provides particular guidance on critical factors in ORC design, primarily the working fluid selection and component selection limitations. Experienced industry engineers have provided advice and
insight regarding the critical design points and processes. The draft standard was reviewed by a number of geothermal industry engineers who have worked with large scale, conventional ORCs. They each
commented on the standard from their prospective in the industry and gave general feedback was that it is a technically relevant standard that can be used as a potential start point to develop a new standard for
the low temperature binary ORC industry. The final draft standard has been submitted to the ISO for consideration.
This thesis first sets out the general background on the state of the art and the industry for lowtemperature binary ORC power plants, and provides the review assessment of the standard draft.
However, the bulk of the thesis is the standard itself. The standard represents a substantial contribution to
the mechanical and thermal systems engineering field.
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Techno-Economic Analysis of Organic Rankine Cycles for a Boiler Station : Energy system modeling and simulation optimizationHudson, Jamel January 2019 (has links)
The Organic Rankine Cycle (ORC) may be the superior cycle for power generation using low temperature and low power heat sources due to the utilization of high molecular mass fluids with low boiling points. They are flexible, simple, easy to operate and maintain, and offer many possible areas of applications including waste heat recovery and power generation from biomass, geothermal and even solar energy. Therefore, they may prove to be of significant importance in reducing global greenhouse gas emission and in the mitigation of climate change. In this thesis the technical feasibility and economic profitability of implementing an ORC in a district heating boiler station is investigated. A model of ORC connected to the hot water circuit of one of the biomass boilers of the boiler station is simulated. The achieved evaporation temperature is estimated to 135 degrees C and the condensation temperature is found to vary in the range of about 70-100 degrees C. The results show that it is both possible and profitable to implement an ORC in the studied boiler station. A maximum net present value of 2.3 MSEK is achieved for a 400 kW system and a maximum internal rate of return of 8.5%, equivalent to a payback period of 9.5 years, is achieved for a 300 kW system. Furthermore, the investment is found to be most sensitive to changes in the electricity price, net electric efficiency and capital expenditure cost.
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Study of Organic Rankine Cycles for Waste Heat Recovery in Transportation VehiclesRoyo Pascual, Lucía 29 June 2017 (has links)
Regulations for ICE-based transportation in the EU seek carbon dioxide
emissions lower than 95 g CO2/km by 2020. In order to fulfill these
limits, improvements in vehicle fuel consumption have to be achieved. One
of the main losses of ICEs happens in the exhaust line. Internal combustion
engines transform chemical energy into mechanical energy through
combustion; however, only about 15-32% of this energy is effectively used
to produce work, while most of the fuel energy is wasted through exhaust
gases and coolant. Therefore, these sources can be exploited to improve the
overall efficiency of the engine. Between these sources, exhaust gases show
the largest potential of Waste Heat Recovery (WHR) due to its high level of
exergy. Regarding WHR technologies, Rankine cycles are considered as the
most promising candidates for improving Internal Combustion Engines.
However, the implementation of this technology in modern passenger cars
requires additional features to achieve a compact integration and controllability
in the engine. While industrial applications typically operates in
steady state operating points, there is a huge challenge taking into account
its impact in the engine during typical daily driving profiles.
This thesis contributes to the knowledge and characterization of an
Organic Rankine Cycle coupled with an Internal Combustion Engine using
ethanol as working fluid and a swash-plate expander as expansion machine.
The main objective of this research work is to obtain and quantify the
potential of Organic Rankine Cycles for the use of residual energy in
automotive engines. To do this, an experimental ORC test bench was
designed and built at CMT (Polytechnic University of Valencia), which can
be coupled to different types of automotive combustion engines. Using
these results, an estimation of the main variables of the cycle was obtained
both in stationary and transient operating points. A potential of increasing
ICE mechanical efficiency up to 3.7% could be reached at points of high
load installing an ORC in a conventional turbocharged gasoline engine.
Regarding transient conditions, a slightly simple and robust control based
on adaptive PIDs, allows the control of the ORC in realistic driving profiles.
High loads and hot conditions should be the starting ideal conditions to
test and validate the control of the ORC in order to achieve high exhaust
temperatures that justify the feasibility of the system.
In order to deepen in the viability and characteristics of this particular
application, some theoretical studies were done. A 1D model was developed
using LMS Imagine.Lab Amesim platform. A potential improvement
of 2.5% in fuel conversion efficiency was obtained at the high operating
points as a direct consequence of the 23.5 g/kWh reduction in bsfc. To
conclude, a thermo-economic study was developed taking into account
the main elements of the installation costs and a minimum Specific Investment
Cost value of 2030 €/kW was obtained. Moreover, an exergetic
study showed that a total amount of 3.75 kW, 36.5% of exergy destruction
rate, could be lowered in the forthcoming years, taking account the maximum
efficiencies considering technical restrictions of the cycle components. / Las normativas anticontaminantes para el transporte propulsado por
motores de combustión interna alternativos en la Unión Europea muestran
límites de emisión menores a 95 g CO2/km para el año 2020. Con el fin
de cumplir estos límites, deberán ser realizadas mejoras en el consumo
de combustible en los vehículos. Una de las principales pérdidas en los
Motores de Combustión Interna Alternativos (MCIA) ocurre en la línea de
escape. Los MCIA transforman la energía química en energía mecánica
a través de la combustión; sin embargo, únicamente el 15-32% de esta
energía es eficazmente usada para producir trabajo, mientras que la mayor
parte es desperdiciada a través de los gases de escape y el agua de refrigeración
del motor. Por ello, estas fuentes de energía pueden ser utilizadas
para mejorar la eficiencia global del vehículo. De estas fuentes, los gases de
escape muestran un potencial mayor de recuperación de energía residual
debido a su mayor contenido exergético. De todos los tipos de Sistemas de
Recuperación de Energía Residual, los Ciclos Rankine son considerados
como los candidatos más prometedores para mejorar la eficiencia de los
MCIA. Sin embargo, la implementación de esta tecnología en los vehículos
de pasajeros modernos requiere nuevas características para conseguir una
integración compacta y una buena controlabilidad del motor. Mientras que
las aplicaciones industriales normalmente operan en puntos de operación
estacionarios, en el caso de los vehículos con MCIA existen importantes
retos teniendo en cuenta su impacto en el modo de conducción cotidianos.
Esta Tesis contribuye al conocimiento y caracterización de un Ciclo
Rankine Orgánico acoplado con un Motor de Combustión Interna Alternativo
utilizando etanol como fluido de trabajo y un expansor tipo Swash-plate
como máquina expansora. El principal objetivo de este trabajo de investigación
es obtener y cuantificar el potencial de los Ciclos Rankine Orgánicos
(ORC) para la recuperación de la energía residual en motores de automoción.
Para ello, una instalación experimental con un Ciclo Rankine
Orgánico fue diseñada y construida en el Instituto Universitario "CMT -
Motores Térmicos" (Universidad Politécnica de Valencia), que puede ser
acoplada a diferentes tipos de motores de combustión interna alternativos.
Usando esta instalación, una estimación de las principales variables del
ciclo fue obtenida tanto en puntos estacionarios como en transitorios. Un
potencial de mejora en torno a un 3.7 % puede ser alcanzada en puntos
de alta carga instalando un ORC en un motor gasolina turboalimentado.
Respecto a las condiciones transitorias, un control sencillo y robusto basado
en PIDs adaptativos permite el control del ORC en perfiles de conducción
reales. Las condiciones ideales para testear y validar el control del ORC
son alta carga en el motor comenzando con el motor en caliente para conseguir
altas temperaturas en el escape que justifiquen la viabilidad de
estos ciclos.
Para tratar de profundizar en la viabilidad y características de esta
aplicación particular, diversos estudios teóricos fueron realizados. Un
modelo 1D fue desarrollado usando el software LMS Imagine.Lab Amesim.
Un potencial de mejora en torno a un 2.5% en el rendimiento efectivo del
motor fue obtenido en condiciones transitorias en los puntos de alta carga
como una consecuencia directa de la reducción de 23.5 g/kWh del consumo
específico. Para concluir, un estudio termo-económico fue desarrollado
teniendo en cuenta los costes de los principales elementos de la instalación
y un valor mínimo de 2030 €/kW fue obtenido en el parámetro de Coste
Específico de inversión. Además, el estudio exergético muestra que un total
de 3.75 kW, 36.5 % de la tasa de destrucción total de exergía, podría ser
reducida en los años futuros, teniendo en cuenta las máximas eficiencias
considerando restricciones técnicas en los componentes del ciclo. / Les normatives anticontaminants per al transport propulsat per motors
de combustió interna alternatius a la Unió Europea mostren límits
d'emissió menors a 95 g·CO2/km per a l'any 2020. Per tal d'acomplir aquests
límits, s'hauran de realitzar millores al consum de combustible dels
vehicles. Una de les principals pèrdues als Motors de combustió interna
alternatius (MCIA) ocorre a la línia d'escapament. Els MCIA transformen
l'energia química en energia mecànica a través de la combustió; però, únicament
el 15-32% d'aquesta energia és usada per produir treball, mentre que
la major part és desaprofitada a través dels gasos d'escapament i l'aigua
de refrigeració del motor. Per això, aquestes fonts d'energia poden ser
utilitzades per millorar l'eficiència global del vehicle. Considerant aquestes
dues fonts d'energia, els gasos d'escapament mostren un potencial major
de recuperació d'energia residual debut al seu major contingut exergètic.
De tots els tipus de Sistemes de Recuperació d'Energia Residual, els Cicles
Rankine són considerats com els candidats més prometedors per millorar
l'eficiència dels MCIA. No obstant, la implementació d'aquesta tecnologia
en els vehicles de passatgers moderns requereix un desenvolupament
addicional per aconseguir una integració compacta i una bona controlabilitat
del motor. Mentre que les aplicacions industrials normalment operen
en punts d'operació estacionaris, en el cas dels vehicles amb MCIA hi
han importants reptes a solucionar tenint en compte el funcionament en
condicions variables del motor i el seu impacte en la manera de conducció
quotidiana del usuari.
Aquesta Tesi contribueix al coneixement i caracterització d'un Cicle
Rankine Orgànic (ORC) acoblat amb un motor de combustió interna alternatiu
(MCIA) utilitzant etanol com a fluid de treball i un expansor tipus
Swash-plate com a màquina expansora. El principal objectiu d'aquest
treball de recerca és obtenir i quantificar el potencial dels ORCs per a la
recuperació de l'energia residual en motors d'automoció. Per aconseguir-ho,
una instal·lació experimental amb un ORC va ser dissenyada i construïda
a l'Institut "CMT- Motores Térmicos" (Universitat Politècnica de València).
Esta installació pot ser acoblada a diferents tipus de MCIAs. Mitjançant
assajos experimentals en aquesta installació, una estimació de les principals
variables del cicle va ser obtinguda tant en punts estacionaris com
en punts transitoris. Un potencial de millora al voltant d'un 3.7% pot ser
aconseguida en punts d'alta càrrega instal·lant un ORC acoblat a un motor
gasolina turboalimentat. Pel que fa a les condicions transitòries, un control
senzill i robust basat en PIDs adaptatius permet el control del ORC en
perfils de conducció reals. Les condicions ideals per a testejar i validar
el control de l'ORC són alta càrrega al motor començant amb el motor en
calent per aconseguir altes temperatures d'escapament que justifiquen la
viabilitat d'aquests cicles.
Per tractar d'aprofundir en la viabilitat i característiques d'aquesta
aplicació particular, diversos estudis teòrics van ser realitzats. Un model
1D va ser desenvolupat usant el programari LMS Imagine.Lab Amesim.
Un potencial de millora al voltant d'un 2.5% en el rendiment efectiu del
motor va ser obtingut en condicions transitòries en els punts d'alta càrrega
com una conseqüència directa de la reducció de 23.5 g/kWh al consum
específic. Per concloure, un estudi termo-econòmic va ser desenvolupat
tenint en compte els costos dels principals elements de la installació i
un valor mínim de 2030 €/kW va ser obtingut en el paràmetre del Cost
Específic d'Inversió. A més, l'estudi exergètic mostra que un total de 3.75
kW, 36.5% de la taxa de destrucció total d'exergia, podria ser recuperat en
un pròxim, considerant restriccions tècniques en els components del cicle i
tenint en compte les màximes eficiències que es poden aconseguir. / Royo Pascual, L. (2017). Study of Organic Rankine Cycles for Waste Heat Recovery in Transportation Vehicles [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/84013 / TESIS
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Power Usage Effectiveness Improvement of High-Performance Computing by Use ofOrganic Rankine Cycle Waste Heat RecoveryTipton, Russell C. 05 June 2023 (has links)
No description available.
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