Thermal Optimization of a Solar Thermal Cooling Cogeneration Plant at Low Temperature Heat Recovery

2014 ◽  
Vol 136 (2) ◽  
Author(s):  
T. Srinivas ◽  
B. V. Reddy
Keyword(s):  
Low Temperature ◽  
Heat Recovery ◽  
High Energy ◽  
Specific Power ◽  
Working Fluid ◽  
Water Mixture ◽  
Thermodynamic Evaluation ◽  
Split Ratio ◽  
Temperature Heat ◽  
Vapor Fraction

A simple cooling cogeneration has been developed by coupling a Kalina cycle system (KCS) with a vapor absorption refrigeration (VAR) system. The working fluid used in this theoretical thermodynamic evaluation is ammonia water mixture. A low temperature heat recovery (150 °C–200 °C) from engine exhaust gas, solar collectors, or similar can be used to operate the plant. A controlling facility is provided to set the required amount of power or cooling to meet the variable demand. In this proposed plant, the liquid refrigerant absorbs more amount of heat from evaporator surroundings with a flow control located in between power and cooling cycles. The extra included components are condenser, heat exchanger and throttling device over KCS plant. Due to possibility of more cooling, it offers high energy utilization factor (EUF). The coupled plant characteristics are studied with changes in mass split ratio, separator vapor fraction, separator temperature, and turbine concentration to develop efficient working conditions. The power mass split ratio is varied from 80% to 100% to run the coupled plant at nearly full load conditions. The separator vapor fraction and temperature are optimized at 45% and 150 °C, respectively. It is recommended to maintain the turbine concentration above 0.85 for optimum power and cooling. The maximum cycle EUF and plant EUF are 0.15 and 0.06, respectively, at 80% power mass split ratio. The specific power and specific cooling at these conditions are 62 kW/kg and 72 kW/kg, respectively.

A Totally Heat-Driven Refrigeration System Using Low-Temperature Heat Sources for Low-Temperature Applications

2019 ◽  
Vol 27 (02) ◽  
pp. 1950012 ◽  
Author(s):  
Zeynab Seyfouri ◽  
Mehran Ameri ◽  
Mozaffar Ali Mehrabian
Keyword(s):  
Low Temperature ◽  
Heat Source ◽  
Rankine Cycle ◽  
Exergy Efficiency ◽  
Working Fluid ◽  
Refrigeration Cycle ◽  
Water Mixture ◽  
Refrigeration System ◽  
Power Requirement ◽  
Temperature Heat

In the present study, a totally heat-driven refrigeration system is proposed and thermodynamically analyzed. This system uses a low-temperature heat source such as geothermal energy or solar energy to produce cooling at freezing temperatures. The proposed system comprises a Rankine cycle (RC) and a hybrid GAX (HGAX) refrigeration cycle, in which the RC provides the power requirement of the HGAX cycle. An ammonia–water mixture is used in both RC and HGAX cycles as the working fluid. A comparative study is conducted in which the proposed system is compared with two other systems using GAX cycle and/or a single stage cycle, as the refrigeration cycle. The study shows that the proposed system is preferred to produce cooling at temperatures from 2∘C to [Formula: see text]C. A detailed parametric analysis of the proposed system is carried out. The results of the analysis show that the system can produce cooling at [Formula: see text]C using a low-temperature heat source at 133.5∘C with the exergy efficiency of about 20% without any input power. By increasing the heat source temperature to 160∘C, an exergy efficiency of 25% can be achieved.

Performance Improvement of a Combined Power and Cooling Cycle for Low Temperature Heat Sources Using Internal Heat Recovery and Scroll Expander

2019 ◽  
Author(s):  
Martina Leveni ◽  
Arun Kumar Narasimhan ◽  
Eydhah Almatrafi ◽  
D. Yogi Goswami
Keyword(s):  
Low Temperature ◽  
Heat Recovery ◽  
Pressure Ratio ◽  
Internal Heat ◽  
Operating Conditions ◽  
Maximum Efficiency ◽  
Water Mixture ◽  
Heat Sources ◽  
Scroll Expander ◽  
Temperature Heat

Abstract Low temperature heat sources inherently result in lower cycle efficiencies, which can be improved by means of combined power and cooling generation. In order to produce power and cooling, appropriate thermodynamic cycles and working fluids must be used. Goswami cycle is a combined cycle that produces power and refrigeration by using ammonia-water mixture for low temperature heat sources. In the present study, a scroll expander is modeled specifically for the cycle operating conditions and a theoretical investigation is conducted to determine the cycle performance. A scroll expander design suitable for the operating conditions improves the power output and thereby overall thermal efficiency. The scroll expander efficiency varied between 0.05 and 0.61 for the pressure ratio between 2.2 and 8.6, with a maximum efficiency of 0.697 achieved at a pressure ratio of about 4.4. An internal heat recovery from the rectifier is proposed along with a flow split in the strong solution and analyzed for overall cycle energy efficiency improvement. Internal heat recovery from the rectifier increased the first law effective efficiency and the effective exergy efficiency by 7.9% and 7.8%, respectively, over the basic configuration.

Experimental Investigations of Oscillatory Fluctuation in an Ammonia-Water Mixture Turbine System

2005 ◽  
Author(s):  
Yoshiharu Amano ◽  
Keisuke Kawanishi ◽  
Takumi Hashizume
Keyword(s):  
Low Temperature ◽  
Heat Source ◽  
Flow Rate ◽  
Mass Fraction ◽  
Working Fluid ◽  
Experimental Investigations ◽  
Water Mixture ◽  
Kalina Cycle ◽  
Ammonia Water ◽  
Temperature Heat

This paper reports results from experimental investigations of the dynamics of an ammonia-water mixture turbine system. The mixture turbine system features Kalina Cycle technology [1]. The working fluid is an ammonia-water mixture (AWM), which enhances the power production recovered from the low-temperature heat source [2], [3]. The Kalina Cycle is superior to the Rankine Cycle for a low temperature heat source [4], [5]. The ammonia-water mixture turbine system has distillation-condensation processes. The subsystem produces ammonia-rich vapor and a lean solution at the separator, and the vapor and the solution converge at the condenser. The mass balance of ammonia and water is maintained by a level control at the separator and reservoirs at the condensers. Since the ammonia mass fraction in the cycle has a high sensitivity to the evaporation/condensation pressure and vapor flow rate in the cycle, the pressure change gives rise to a flow rate change and then level changes in the separators and reservoirs and vice versa. From the experimental investigation of the ammonia-water mixture turbine system, it was observed that the sensitivity of the evaporating flow rate and solution liquid density in the cycle is very high, and those sensitivity factors are affected by the ammonia-mass fraction. This paper presents the experimental results of a study on the dynamics of the distillation process of the ammonia-water mixture turbine system and uses the results of investigation to explain the mechanism of the unstable fluctuation in the system.

scholarly journals Comparison of the Trilateral Flash Cycle and Rankine Cycle with Organic Fluid Using the Pinch Point Temperature

Entropy ◽  
2019 ◽  
Vol 21 (12) ◽  
pp. 1197
Author(s):  
Kai-Yuan Lai ◽  
Yu-Tang Lee ◽  
Miao-Ru Chen ◽  
Yao-Hsien Liu
Keyword(s):  
Low Temperature ◽  
Heat Recovery ◽  
Waste Heat Recovery ◽  
Waste Heat ◽  
Rankine Cycle ◽  
Operating Conditions ◽  
Heat Extraction ◽  
Working Fluid ◽  
Pinch Point ◽  
Temperature Heat

Low-temperature heat utilization can be applied to waste heat from industrial processes or renewable energy sources such as geothermal and ocean energy. The most common low-temperature waste-heat recovery technology is the organic Rankine cycle (ORC). However, the phase change of ORC working fluid for the heat extraction process causes a pinch-point problem, and the heat recovery cannot be efficiently used. To improve heat extraction and power generation, this study explored the cycle characteristics of the trilateral flash cycle (TFC) in a low-temperature heat source. A pinch-point-based methodology was developed for studying the optimal design point and operating conditions and for optimizing working fluid evaporation temperature and mass flow rate. According to the simulation results, the TFC system can recover more waste heat than ORC under the same operating conditions. The net power output of the TFC was approximately 30% higher than ORC but at a cost of higher pump power consumption. Additionally, the TFC was superior to ORC with an extremely low-temperature heat source (<80 °C), and the ideal efficiency was approximately 3% at the highest work output condition. The TFC system is economically beneficial for waste-heat recovery for low-temperature heat sources.

Heat Recovery Using Organic Rankine Cycle

Vestnik MEI ◽  
2021 ◽  
pp. 51-57
Author(s):  
Dakkah Baydaa Bo ◽  
◽  
I′ldar A. Sultanguzin ◽  
Yuriy V. Yavorovsky ◽  
◽  
...  
Keyword(s):  
Low Temperature ◽  
Heat Exchangers ◽  
Heat Recovery ◽  
Test Bench ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Heat Losses ◽  
Working Fluid ◽  
Gear Pump ◽  
Temperature Heat

Heat losses in industrial processes can be divided into three sections (high-, medium-, and low-temperature heat), depending on the temperature of the exhaust gases. This heat is usually recovered either by heat exchangers or by a closed Rankine cycle. However, about 60% of low-temperature heat losses remain irreplaceable. Currently, the organic Rankine cycle has become a promising method of low-temperature energy recovery, and several theoretical studies on this topic have appeared, but a small number of experimental studies have been performed. In our work, we have built a 2 kW heat recovery laboratory test bench using tube-type heat exchangers, a gear pump and a turbo expander on the working fluid R141b. As a result, we found that the efficiency of the cycle increases as the boiling point and pressure increase, but an increase in overheating at the inlet of the expander leads to a decrease in efficiency due to the use of the working fluid R141b. At the inlet of the evaporator and the outlet of the condenser, respectively, overheating and supercooling of the working fluid occurs, which negatively affects the efficiency of the cycle. The amount of useful heat obtained was 45.4 W with an efficiency of 2.24%. as a result of low efficiency of the expander and pump, as well as leaks during the test. The development of an experimental test bench with working on organic Rankin cycle requires long-term research work and great scientific potential. In the future, it will be necessary to create a new test bench based on a deeper study, so that we can get a higher efficiency of the expander and pump, which would affect the efficiency of this cycle. Also, we need to replace the working fluid in the cycle with a more efficient one.

scholarly journals Thermodynamic analysis of a Carbon Carrier Cycle (CCC) for low temperature heat recovery

2021 ◽  
Vol 238 ◽  
pp. 01002
Author(s):  
Diego Micheli ◽  
Mauro Reini ◽  
Rodolfo Taccani
Keyword(s):  
Low Temperature ◽  
Heat Source ◽  
Heat Recovery ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Performance Comparison ◽  
Working Fluid ◽  
Power Cycle ◽  
Carbon Carrier ◽  
Temperature Heat

The aim of the paper is to study the thermodynamic behavior of a non-conventional power cycle, named Carbon Carrier Cycle (CCC), which is expected to obtain interesting performance with low temperature heat source. The CCC may be regarded as derived from an absorption machine, where an expander replaces the condenser, the throttling valve and the evaporator. The working fluid is a mixture of CO2 and a proper absorber. In the paper, the thermodynamic model of this kind of cycles is described, and the results obtained considering Acetone as the absorber are discussed. A first performance comparison is then conducted with a more conventional Organic Rankine Cycle (ORC).

A review of low-temperature heat recovery technologies for industry processes

2019 ◽  
Vol 27 (10) ◽  
pp. 2227-2237 ◽  
Author(s):  
Li Xia ◽  
Renmin Liu ◽  
Yiting Zeng ◽  
Peng Zhou ◽  
Jingjing Liu ◽  
...  
Keyword(s):  
Low Temperature ◽  
Heat Recovery ◽  
Temperature Heat

Novel Combined Power and Cooling Thermodynamic Cycle for Low Temperature Heat Sources, Part II: Experimental Investigation

2003 ◽  
Vol 125 (2) ◽  
pp. 223-229 ◽  
Author(s):  
Gunnar Tamm ◽  
D. Yogi Goswami
Keyword(s):  
Low Temperature ◽  
System Analysis ◽  
Waste Heat ◽  
Thermal Power ◽  
Experimental System ◽  
Thermodynamic Cycle ◽  
Operating Conditions ◽  
Working Fluid ◽  
Water Mixture ◽  
Theoretical Simulation

A combined thermal power and cooling cycle proposed by Goswami is under intensive investigation, both theoretically and experimentally. The proposed cycle combines the Rankine and absorption refrigeration cycles, producing refrigeration while power is the primary goal. A binary ammonia-water mixture is used as the working fluid. This cycle can be used as a bottoming cycle using waste heat from a conventional power cycle or as an independent cycle using low temperature sources such as geothermal and solar energy. An experimental system was constructed to demonstrate the feasibility of the cycle and to compare the experimental results with the theoretical simulation. Results showed that the vapor generation and absorption condensation processes work experimentally, exhibiting expected trends, but with deviations from ideal and equilibrium modeling. The potential for combined turbine work and refrigeration output was evidenced in operating the system. Analysis of losses showed where improvements could be made, in preparation for further testing over a broader range of operating conditions.

scholarly journals Low temperature heat recovery in engine coolant for stationary and road transport applications

2017 ◽  
Vol 129 ◽  
pp. 834-842 ◽  
Author(s):  
Pierre Leduc ◽  
Pascal Smague ◽  
Arthur Leroux ◽  
Gabriel Henry
Keyword(s):  
Low Temperature ◽  
Heat Recovery ◽  
Road Transport ◽  
Temperature Heat ◽  
Engine Coolant

Combined Cycle for Power Generation and Refrigeration Using Low Temperature Heat Sources

2014 ◽  
Vol 3 (3) ◽  
pp. 34-56 ◽  
Author(s):  
Vijay Chauhan ◽  
P. Anil Kishan ◽  
Sateesh Gedupudi
Keyword(s):  
Power Generation ◽  
Low Temperature ◽  
Combined Cycle ◽  
Working Fluid ◽  
Heat Sources ◽  
Ambient Temperatures ◽  
Temperature Heat ◽  
Good Potential ◽  
Output Ratio ◽  
Operation Results

A combined refrigeration and power cycle, which uses ammonia-water as the working fluid, is proposed by combining Rankine and vapour absorption cycles with an advantage of varying refrigeration capacity to power output ratio. The study investigates the usage of low temperature heat sources for the cycle operation. Results of parametric analysis are presented, which show the scope for optimization. Results of thermodynamic optimization of the cycle for second law efficiency performed using genetic algorithm for different ambient temperatures are also presented. The cycle shows good potential for obtaining refrigeration and power generation.

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