A new approach for optimization of combined cycle system based on first level of exergy destruction splitting

2020 ◽  
Vol 37 ◽  
pp. 100600
Author(s):  
R. Akbarpour Ghiasi ◽  
M. Fallah ◽  
S. Lotfan ◽  
M.A. Rosen
Keyword(s):  
Combined Cycle ◽  
Exergy Destruction ◽  
New Approach ◽  
Cycle System

Genetic Algorithm for Multi-Objective Exergetic and Economic Optimization of Parabolic Trough Collectors Integration Into Combined Cycle System (ISCCS)

2010 ◽  
Author(s):  
Ali Baghernejad ◽  
Mahmood Yaghoubi
Keyword(s):  
Decision Making ◽  
Pareto Frontier ◽  
Optimal Solution ◽  
Combined Cycle ◽  
Exergy Destruction ◽  
Exergetic Efficiency ◽  
Economic Optimization ◽  
Cost Rate ◽  
Multi Objective ◽  
Cycle System

Thermoeconomic analyses of any thermal system design are always based on the economic objectives. However, knowledge of economic optimization may not be sufficient for decision making process, since solutions with higher thermodynamic efficiency, in spite of small increases in total costs, may result in much more interesting designs due to changes in the energy market prices or in the energy policies. In this paper a multi-objective optimization scheme is developed and applied for an Integrated Solar Combined Cycle System (ISCCS) that produces 400 MW of electricity to find solutions that simultaneously satisfy exergetic as well as economic objectives. This corresponds to search for a set of Pareto optimal solutions with respect to the two competing objectives. The optimization process is carried out by a particular class of search algorithms known as multi-objective evolutionary algorithms (MOEAs). For such MOEAs, an example of decision-making is presented and a final optimal solution has been introduced. The final optimal solution that is selected in this analysis belongs to the region of Pareto Frontier with significant sensitivity to the costing parameters. However, the region with lower sensitivity to the costing parameter is not reasonable for the final optimum solution due to a weak equilibrium of Pareto Frontier in which a small changes in exergetic efficiency of plant due to variation of operating parameters may lead to the danger of increasing the cost rate of product, drastically. The analysis shows that optimization process leads to 3.2% increasing in the exergetic efficiency and 3.82% decreasing of the rate of product cost. Also optimization leads to the 2.73% reduction on the fuel exergy, 5.71% reductions in the total exergy destruction and also 3.46% and 7.32% reductions in the fuel cost rate and cost rate relating to the exergy destruction, respectively.

scholarly journals Assessment of an integrated solar combined cycle system based on conventional and advanced exergetic methods

2021 ◽  
pp. 325-325
Author(s):  
Shucheng Wang ◽  
Pengcheng Wei ◽  
Sajid Sajid ◽  
Lei Qi ◽  
Mei Qin
Keyword(s):  
Combustion Chamber ◽  
Solar Collector ◽  
Combined Cycle ◽  
Exergy Destruction ◽  
Parabolic Trough ◽  
Destruction Rate ◽  
Economic Significance ◽  
Cycle System ◽  
Parabolic Trough Solar Collector ◽  
Advanced System

An integrated solar combined cycle system based on parabolic trough solar collector and combined cycle power plant is proposed. The advanced system is socio-economic significance compared to traditional combined cycle power system. Plainly, the exergetic analyses (exergy destruction and efficiency) via conventional and advanced methods are used for thermodynamic properties of the integrated solar combined cycle system components. In addition, the exergy destruction is divided into endogenous, exogenous, avoidable, and unavoidable. The results show that the combustion chamber has the largest fuel exergy and the highest endogenous exergy destruction rate of 1001.60 MW and 213.87 MW, respectively. Additionally, the combustion chamber has the highest exergy destruction rate of 235.60 MW(60.29%), followed by the parabolic trough solar collector of 54.20 MW(13.87%). For overall system, the endogenous exergy destruction rate of 320.83 MW (82.10%) and exogenous exergy destruction rate of 69.97 MW (17.90%) are resulted via the advanced exergy analysis method. Besides?Several methods to reduce the exergy destruction and improve the components? efficiency are put forward.

scholarly journals 4E Analysis of a Fuel Cell and Gas Turbine Hybrid Energy System

2020 ◽  
Vol 11 (1) ◽  
pp. 7568-7579
Keyword(s):  
Fuel Cell ◽  
Cell Voltage ◽  
Energy System ◽  
High Energy ◽  
Exergy Efficiency ◽  
Combined Cycle ◽  
Net Energy ◽  
Exergy Destruction ◽  
Molten Carbonate ◽  
Ambient Temperatures

Exergy analysis of the expansion turbine hybrid cycle of integrated molten carbonate fuel cells is presented in this study. The proposed cycle was used as a sustainable energy curriculum to provide a small hybrid power plant with high energy efficiency. To generate electricity with the system mentioned above, and externally repaired fusion carbon fuel cell was used located at the top of the combined cycle. Moreover, the turbine and steam turbine systems are considered as complementary and bottom layers for co-generation, respectively. The results showed that the proposed system could reach net energy of up to 1125 kilowatts, while the total exergy efficiency (including electricity and heat) for this system is more than 68%. Moreover, the energy supplied and exergy efficiency derived from the proposed cycle are stable versus changes in ambient temperatures. Besides, the effect of increasing the current density on the cell voltage and the total exergy destruction was considered. Also, the new approaches of the exergoeconomics and exergoenvironmental analysis are implemented in this system. The results show that the hybrid system can decrease the exergy destruction costs more than 16%, and the environmental footprint of the system more than 23.4%.

scholarly journals Reaching for 60 Percent

2002 ◽  
Vol 124 (04) ◽  
pp. 35-39 ◽  
Author(s):  
Michael Valenti
Keyword(s):  
New York ◽  
High Pressure ◽  
Fuel Economy ◽  
Environmental Performance ◽  
New York State ◽  
Combined Cycle ◽  
York State ◽  
Cycle System ◽  
The World ◽  
H Design

The General Electric (GE) H turbine system in Wales is designed to be 60% thermally efficient. The Welsh installation will serve as a springboard for two other installations, planned for New York State and Tokyo, so that the technology will span three continents. The 480-megawatt H system in Wales is designed to be the first gas turbine combined-cycle system in the world to achieve 60% thermal efficiency. The main advantage provided by efficiency is economic, because fuel represents the largest single expense in running a fossil-fueled power plant. GE engineers based much of the H design on proven turbine technology, starting with the high-pressure compressors. Another advantage GE intends to stress in marketing its H turbines, along with fuel economy and environmental performance, is their greater power density.

Design and Analysis of Fluidless Cooling Devices for High Speed Machining

1995 ◽  
Author(s):  
Samir B. Billatos ◽  
Nadia A. Basaly
Keyword(s):  
High Speed ◽  
Surface Characteristics ◽  
Work Piece ◽  
High Speed Machining ◽  
Element Analysis ◽  
New Approach ◽  
Cycle System ◽  
Increase Production Cost ◽  
Harmful Effects ◽  
Interface Heat

Abstract In high speed machining, the generated heat produces very high temperatures at the tool-work interface. Heat generated at the cutting area may shorten tool life, damage work piece surface, affect surface characteristics, and hence increase production cost. To deal with these problems, cutting fluids are used. Unfortunately, these fluids cause harmful effects to the operators and serious problems of pollution to the environment. Therefore, a new approach is developed to reduce the cutting tool temperature without using external coolants, and thus considerably reduce the amount of the hazardous waste being disposed to the environment. It removes a portion of the generated heat from the tool-work interface by flowing water in a closed cooling cycle system. The approach was analyzed and verified using Finite Element Analysis. Results were compared to the dry and wet cutting cases obtained from literature, and it was found that temperatures on the flank and rake faces of the tool can be lowered, and the overheated area of the tool tip, and consequently its wear, can be reduced significantly.

scholarly journals How to Construct a Combined S-CO2 Cycle for Coal Fired Power Plant?

Entropy ◽  
2018 ◽  
Vol 21 (1) ◽  
pp. 19 ◽  
Author(s):  
Enhui Sun ◽  
Han Hu ◽  
Hangning Li ◽  
Chao Liu ◽  
Jinliang Xu
Keyword(s):  
Power Plant ◽  
Flue Gas ◽  
Heat Recovery ◽  
Water Cycle ◽  
Combined Cycle ◽  
Exergy Destruction ◽  
Generation Efficiency ◽  
Air Preheater ◽  
Recompression Cycle ◽  
Residual Heat

It is difficult to recover the residual heat from flue gas when supercritical carbon dioxide (S-CO2) cycle is used for a coal fired power plant, due to the higher CO2 temperature in tail flue and the limited air temperature in air preheater. The combined cycle is helpful for residual heat recovery. Thus, it is important to build an efficient bottom cycle. In this paper, we proposed a novel exergy destruction control strategy during residual heat recovery to equal and minimize the exergy destruction for different bottom cycles. Five bottom cycles are analyzed to identify their differences in thermal efficiencies (ηth,b), and the CO2 temperature entering the bottom cycle heater (T4b) etc. We show that the exergy destruction can be minimized by a suitable pinch temperature between flue gas and CO2 in the heater via adjusting T4b. Among the five bottom cycles, either the recompression cycle (RC) or the partial cooling cycle (PACC) exhibits good performance. The power generation efficiency is 47.04% when the vapor parameters of CO2 are 620/30 MPa, with the double-reheating-recompression cycle as the top cycle, and RC as the bottom cycle. Such efficiency is higher than that of the supercritical water cycle power plant.

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