scholarly journals Combined Cycle Consisting of Closed Processes Based Cycle Powered by A Reversible Heat Pump that Exceed Carnot Factor

2019 ◽  
Vol 15 ◽  
pp. 6078-6100
Author(s):  
Ramon Ferreiro Garcia ◽  
Jose Carbia carril
Keyword(s):  
Energy Conversion ◽  
Case Studies ◽  
Heat Pump ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Combined Cycle ◽  
Power Ratio ◽  
Primary Cycle ◽  
Case Based

This article deals with the task of analysing a feasible reversible combined cycle composed of a heat pump as the primary cycle and a non-condensing mode thermal engine characterized by operating under a closed processes based cycle that work by adding and releasing heat, as the secondary cycle. Two case studies are analysed and compared. According to the results, the case study based on the combination of a heat pump cycle with an organic Rankine cycle, is the paradigm of a reversible 100% efficient combined cycle. The case study based on a heat pump cycle and a reversible heating-cooling based cycle is the paradigm of a super-efficient combined cycle that yields a 1.486 power ratio (PR) or 148.6% efficiency. Further, the case based on a heat pump cycle with a regenerative irreversible heating-cooling based cycle, is the paradigm of energy conversion and energy generation that yields a 1.29 PR or 129% efficiency assuming limited irreversibilities. This article deals with the task of analysing a feasible reversible combined cycle composed of a heat pump as the primary cycle and a non-condensing mode thermal engine characterized by operating under a closed processes based cycle that work by adding and releasing heat, as the secondary cycle. Two case studies are analysed and compared. According to the results, the case study based on the combination of a heat pump cycle with an organic Rankine cycle, is the paradigm of a reversible 100% efficient combined cycle. The case study based on a heat pump cycle and a reversible heating-cooling based cycle is the paradigm of a super-efficient combined cycle that yields a 1.486 power ratio (PR) or 148.6% efficiency. Further, the case based on a heat pump cycle with a regenerative irreversible heating-cooling based cycle, is the paradigm of energy conversion and energy generation that yields a 1.29 PR or 129% efficiency assuming limited irreversibilities.

Organic Rankine Cycle Working Fluid Selection and Performance Analysis for Combined Application With a 2 MW Class Industrial Gas Turbine

2014 ◽  
Author(s):  
Karsten Kusterer ◽  
René Braun ◽  
Dieter Bohn
Keyword(s):  
Heat Source ◽  
Energy Conversion ◽  
Gas Turbine ◽  
Power Output ◽  
Waste Heat ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Combined Cycle ◽  
Working Fluid ◽  
Combined Operation

The selection of suitable working fluids for use in Organic Rankine Cycles (ORC) is strongly addicted to the intended application of the ORC system. The design of the ORC, the kind of heat source and the ambient condition has an influence on the performance of the Organic Rankine Cycle and on the selection of the working fluid. It can come to a discrepancy between the best candidate from the thermodynamic point of view and the transformation into a real machine design. If an axial turbine design is considered for expansion and energy conversion within the ORC, the vapor volume flow ratios within the expansion path, the pressure ratio and of course the number of stages have to be considered within the fluid selection process and for the design parameters. Furthermore, environmental aspects have to be taken into account, e.g. the global warming potential (GWP) and the flammability of the selected fluid. This paper shows the results of the design and fluid selection process for an Organic Rankine Cycle for application in a combined operation with a 2MW class industrial gas turbine. The gas turbine contains two radial compressor stages with an integrated intercooler. To further increase the thermal cycle efficiency, a recuperator has been implemented to the gas turbine cycle, which uses the exhaust gas waste heat to preheat the compressed air after the second compressor, before it enters the combustion chamber. The shaft power is generated by a three stage axial turbine, whereby the first stage is a convection cooled stage, due to a turbine inlet temperature of 1100°C. To further increase the electrical efficiency and the power output of the energy conversion cycle, a combined operation with an organic Rankine cycle is intended. Therefore the waste heat from the GT compressor intercooler is used as first heat source and the waste heat of the exhaust gas after the recuperator as second heat source for the Organic Rankine Cycle. It is intended that the ORC fluid acts as heat absorption fluid within the compressor intercooler. Due to these specifications for the ORC, a detailed thermodynamic analysis has been performed to determine the optimal design parameter and the best working fluid for the ORC, in order to obtain a maximum power output of the combined cycle. Due to the twice coupling of the ORC to the GT cycle, the heat exchange between the two cycles is bounded by each other and a detailed analysis of the coupled cycles is necessary. E.g. the ambient temperature has an enormous influence on the transferred heat from the intercooler to the ORC cycle, which itself affects the heat transfer and temperatures of the transferable heat from the second heat source. Thus, a detailed analysis by considering the ambient operation conditions has been performed, in order to provide a most efficient energy conversion system over a wide operation range. The performance analysis has shown that by application of an ORC for a combined operation with the intercooled and recuperated gas turbine, the combined cycle efficiency can be increased, for a wide ambient conditions range, by more than 3 %pts. and the electrical power output by more than 10 %, in comparison to the stand alone intercooled and recuperated gas turbine.

Triple Cycle: A Conceptual Arrangement of Multiple Cycle Toward Optimal Energy Conversion

2002 ◽  
Vol 124 (2) ◽  
pp. 429-436 ◽  
Author(s):  
T. C. Hung
Keyword(s):  
Energy Conversion ◽  
Waste Heat ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Combined Cycle ◽  
Significant Difference ◽  
Energy Conversion Systems ◽  
Multiple Cycle ◽  
Series Type ◽  
Parallel Type

The purpose of this study is to find a maximum work output from various combinations of thermodynamic cycles from a viewpoint of the cycle systems. Three systems were discussed in this study: a fundamental combined cycle and two other cycles evolved from the fundamental dual combined cycle: series-type and parallel-type triple cycles. In each system, parametric studies were carried out in order to find optimal configurations of the cycle combinations based on the influences of tested parameters on the systems. The study shows that the series-type triple cycle exhibits no significant difference as compared with the combined cycle. On the other hand, the efficiency of the parallel-type triple cycle can be raised, especially in the application of recovering low-enthalpy-content waste heat. Therefore, by properly combining with a steam Rankine cycle, the organic Rankine cycle is expected to efficiently utilize residual yet available energy to an optimal extent. The present study has pointed out a conceptual design in multiple-cycle energy conversion systems.

Managing Case-Based Learning with Interactive Case Study Libraries

2010 ◽  
pp. 351-371
Author(s):  
Hao Jiang ◽  
John M. Carroll ◽  
Craig Ganoe
Keyword(s):  
Case Studies ◽  
Learning Management Systems ◽  
Learning Systems ◽  
Pedagogical Approach ◽  
Design And Implementation ◽  
Case Based Learning ◽  
Case Libraries ◽  
Interactive Case Study ◽  
Case Based

This chapter discusses a particular pedagogical methodology, case-based learning, and introduces an application that supports case studies. It suggests that authenticity, social interaction, community of practice, and resource accumulation are especially important for design and implementation of case-based learning systems. To make the arguments more vivid, the chapter also introduces a case study library that supports usability engineering education. Some of the suggestions are more related to case libraries or systems alike in particular, and some are valuable for learning management systems in general. The authors hope their study can invoke further research of computer-supported case studies in educational and CSCL communities, and more applications supporting this pedagogical approach will be developed.

Technical and Economical Feasibility of Biomass Use for Power Generation in Sicily

2012 ◽  
Vol 3 (1) ◽  
pp. 40-50 ◽  
Author(s):  
Antonio Messineo ◽  
Domenico Panno ◽  
Roberto Volpe
Keyword(s):  
Power Plant ◽  
Sustainable Management ◽  
Power Plants ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Geographical Information ◽  
Critical Issues ◽  
Economical Feasibility ◽  
Choice Of Technology

Biomass can provide a reliable support for production of biofuels while contributing to sustainable management of natural resources. Many countries, including Italy, have introduced important incentive schemes to support the use of biomass for electricity, heat and transportation. This has raised considerable interest towards the use of biomass for energy generation purposes. Nonetheless, the design and installation of biomass-fuelled power plants present several critical issues, such as choice and availability of biomass, choice of technology, power plant localization and logistics. The case study tackled in this paper evaluates the economies originated by a 1MWel Organic Rankine Cycle (ORC) turbine coupled with a biomass fuelled boiler, installed in an area close to Palermo (Italy). A Geographical Information System (GIS) was used to localize the power plant and to optimize logistics. The thermodynamics of the plant as a whole were also analyzed. Finally, two different scenarios were simulated for project financial evaluation.

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