scholarly journals Thermodynamic Performance Analysis of Turbine-Bleeding Organic Rankine Cycle with and without Regeneration

2018 ◽  
Vol 2 (1) ◽  
pp. 23-28
Author(s):  
Keyword(s):  
Performance Analysis ◽  
System Performance ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Inlet Pressure ◽  
Working Fluid ◽  
Low Grade ◽  
System Parameters ◽  
Turbine Inlet ◽  
Thermodynamic Performance

This paper presents a thermodynamic performance analysis of turbine-bleeding organic Rankine cycle (ORC) with and without regeneration using internal heat exchanger based on the first and second thermodynamic laws for the recovery of low-grade finite heat source. The effects of the important system parameters including turbine bleeding pressure, turbine inlet pressure, and working fluid on the system performance were intensively investigated. Results showed that there exists an optimum turbine bleeding pressure for the maximum second-law efficiency. The system performance under the optimal condition is significantly influenced by the turbine inlet pressure, regeneration, and working fluid. The greatest exergy destruction of the system varies depending on the system parameters.

A Thermodynamic Analysis of Cogeneration System in Parallel Circuit Based on Organic Rankine Cycle

2012 ◽  
Vol 505 ◽  
pp. 534-538 ◽  
Author(s):  
Kyoung Hoon Kim ◽  
Se Woong Kim ◽  
Hyung Jong Ko
Keyword(s):  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Inlet Pressure ◽  
Working Fluid ◽  
Second Law ◽  
Low Grade ◽  
Source Temperature ◽  
Turbine Inlet ◽  
Cogeneration System ◽  
Parallel Circuit

The combined heat and power generation system using Organic Rankine Cycle (ORC) has become a promising technology for efficient conversion of low-grade heat source to useful form of energy. In this study thermodynamic performance is investigated for a cogeneration system which consists of ORC power plant and an additional process heater as a parallel circuit. Nine different kinds of fluids of R143a, R22, R134a, R152a, R123, R113, isobutene, butane, and isopentane are considered as a working fluid of ORC. The effects of system parameters such as turbine inlet pressure, source temperature, and process heat load on the system performance including ratio of mass flow rates, net work production, and the first and second law efficiencies of thermodynamics for each fluid. Results show that there exists an optimal turbine inlet pressure to yield maximum net work. The selection of the working fluid for the combined system which assumes the maximum second-law efficiency is dependent on the source temperature level.

scholarly journals Conversion of Low-Grade Heat from Multiple Streams in Methanol to Olefin (MTO) Process Based on Organic Rankine Cycle (ORC)

2020 ◽  
Vol 10 (10) ◽  
pp. 3617 ◽  
Author(s):  
Danchen Wei ◽  
Cheng Liu ◽  
Zhongfeng Geng
Keyword(s):  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Exergy Efficiency ◽  
Working Fluid ◽  
Low Grade ◽  
Maximum Output ◽  
Methanol To Olefin ◽  
Thermodynamic Performance ◽  
Selection Of ◽  
Mto Process

The organic rankine cycle (ORC) has been widely used to convert low-grade thermal energy to electricity. The selection of the cycle configuration, working fluid, and operating parameters is crucial for the economic profitability of the ORC system. In the methanol to olefin (MTO) process, multi-stream low-temperature waste heat has not been effectively utilized. The previous study mostly focused on the optimization of a single stream system and rarely considered the comprehensive optimization of multi-stream ORC systems which have multi-temperature heat sources. This paper proposes five kinds of system design schemes, and determines the optimal output work and the highest exergy efficiency through the selection of working fluid and optimization of system parameters. In addition, the influence of mixed working fluid on the thermodynamic performance of the system was also investigated. It is found that there is an optimal evaporation temperature due to the restriction of pinch temperature. At the optimal temperature the ORC system obtains the maximum net output power of 4.95 MW. The optimization results show that the working fluid R227EA selected from seven candidate working fluids shows the optimal thermodynamic performance in all the five design schemes, and obtains the maximum output work and exergy efficiency.

Analysis of Cogeneration System in Series Circuit Based on Regenerative Organic Rankine Cycle

2012 ◽  
Vol 505 ◽  
pp. 519-523 ◽  
Author(s):  
Kyoung Hoon Kim ◽  
Hyung Jong Ko ◽  
Se Woong Kim
Keyword(s):  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Inlet Pressure ◽  
Working Fluid ◽  
Combined System ◽  
Working Fluids ◽  
Source Temperature ◽  
Turbine Inlet ◽  
Cogeneration System ◽  
In Series

In this paper thermodynamic performance of a combined heat and power cogeneration system driven by low-temperature source is investigated. The system consists of regenerative Organic Rankine Cycle (ORC) and an additional process heater as a series circuit. Seven working fluids of isobutene, butane, R11, R123, isopentane, normal pentane, and R113 are considered in this work. Special attention is paid to the effects of system parameters such as the turbine inlet pressure or source temperature on the characteristics of the system such as the ratio of mass flow rates, net work production as well as the efficiencies of the first and second laws of thermodynamics for various working fluids. This study finds that higher turbine inlet pressure leads to lower second law efficiency of ORC system but higher that of the combined system. Results also show that the optimum working fluid varies with the source temperature.

scholarly journals Performance Analysis of Transcritical Carbon Dioxide Rankine Cycle with Regenerator

2018 ◽  
Vol 225 ◽  
pp. 05020
Author(s):  
Aklilu T. Baheta ◽  
Sintayehu M. Hailegiorgis ◽  
Ahmed N. Oumer ◽  
Shaharin Anwar B Sulaiman
Keyword(s):  
Carbon Dioxide ◽  
Rankine Cycle ◽  
Operating Conditions ◽  
Inlet Pressure ◽  
Working Fluid ◽  
Inlet Temperature ◽  
Low Grade ◽  
Turbine Inlet Temperature ◽  
Turbine Inlet ◽  
Transcritical Carbon Dioxide

Transcritical carbon dioxide Rankine cycle (TCRC) has a potential to convert low grade heat source into power. Thus, the objective of this paper is to evaluate TCRC performance based on the first and the second law of thermodynamics for wide and different operating conditions. To address this, TCRC thermal efficiency, exergetic efficiency, utilization ratio and the exergy destruction of the components are analyzed parametrically. Engineering Equation Solver (EES) is used to solve the set of equations and to evaluate the working fluid properties at the given conditions. For the analysis compressor efficiency, turbine efficiency and effectiveness of the regenerator are assumed to be 0.9, 0.9 and 0.95, respectively. The pump inlet pressure was assumed to be 6.2 MPa. It is found that at 10 MPa turbine inlet pressure 240°C is the optimal turbine inlet temperature operating condition. The percentage of exergy destructions at 240°C turbine inlet temperature are 0.94, 4.53, 9.55, 41.23, and 43.74 by the pump, turbine, condenser, heater and regenerator, respectively. Hence, the highest and the smallest exergy destructions are in the regenerator and the pump. This study will help to select the potential component for further improvement.

scholarly journals Performance Analysis and Working Fluid Selection of a Supercritical Organic Rankine Cycle for Low Grade Waste Heat Recovery

Energies ◽  
2012 ◽  
Vol 5 (9) ◽  
pp. 3233-3247 ◽  
Author(s):  
Hong Gao ◽  
Chao Liu ◽  
Chao He ◽  
Xiaoxiao Xu ◽  
Shuangying Wu ◽  
...  
Keyword(s):  
Performance Analysis ◽  
Heat Recovery ◽  
Waste Heat Recovery ◽  
Waste Heat ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Working Fluid ◽  
Low Grade ◽  
Working Fluid Selection ◽  
Selection Of

1-D Model Analysis of Tesla Turbine for Small Scale Organic Rankine Cycle (ORC) System

2017 ◽  
Author(s):  
Jian Song ◽  
Chun-wei Gu
Keyword(s):  
Large Scale ◽  
Low Cost ◽  
Organic Rankine Cycle ◽  
Axial Flow ◽  
Rankine Cycle ◽  
Expansion Ratio ◽  
Working Fluid ◽  
Small Scale ◽  
Low Grade ◽  
D Model

Energy shortage and environmental deterioration are two crucial issues that the developing world has to face. In order to solve these problems, conversion of low grade energy is attracting broad attention. Among all of the existing technologies, Organic Rankine Cycle (ORC) has been proven to be one of the most effective methods for the utilization of low grade heat sources. Turbine is a key component in ORC system and it plays an important role in system performance. Traditional turbine expanders, the axial flow turbine and the radial inflow turbine are typically selected in large scale ORC systems. However, in small and micro scale systems, traditional turbine expanders are not suitable due to large flow loss and high rotation speed. In this case, Tesla turbine allows a low-cost and reliable design for the organic expander that could be an attractive option for small scale ORC systems. A 1-D model of Tesla turbine is presented in this paper, which mainly focuses on the flow characteristics and the momentum transfer. This study improves the 1-D model, taking the nozzle limit expansion ratio into consideration, which is related to the installation angle of the nozzle and the specific heat ratio of the working fluid. The improved model is used to analyze Tesla turbine performance and predict turbine efficiency. Thermodynamic analysis is conducted for a small scale ORC system. The simulation results reveal that the ORC system can generate a considerable net power output. Therefore, Tesla turbine can be regarded as a potential choice to be applied in small scale ORC systems.

Performance Analysis of a Solar-Assisted Organic Rankine Cycle

2020 ◽  
Author(s):  
M. T. Nitsas ◽  
I. P. Koronaki
Keyword(s):  
Mathematical Model ◽  
Performance Analysis ◽  
Temporal Variation ◽  
Storage Tank ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Working Fluid ◽  
Evaporation Temperature ◽  
Solar Powered ◽  
The Mathematical Model

Abstract The objective of this paper is the thermodynamic analysis of a solar powered Organic Rankine Cycle (O.R.C.) and the investigation of potential working fluids in order to select the optimum one. A dynamic model for a solar O.R.C. with a storage tank, which produces electricity is developed. The mathematical model includes all the equations that describe the operation of the solar collectors, the storage tank, the Rankine Cycle and the feedback between them. The model runs for representative days throughout the year, calculating the net produced energy as a function of the selected evaporation temperature for every suitable working fluid. Above that, the temporal variation of the systems’ temperatures, collectors’ efficiency and net produced power, for the optimum organic fluid and evaporation temperature are presented.

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