An exhaust heat recovery generator is proposed to be integrated with conventional gas-fired triple-effect LiBr/water absorption cooling cycles to improve system energy efficiency. As a case study, simulation of the no...An exhaust heat recovery generator is proposed to be integrated with conventional gas-fired triple-effect LiBr/water absorption cooling cycles to improve system energy efficiency. As a case study, simulation of the novel cycle based on promising parallel flow with cooling capacity of 1 150 kW is carried out under various heat recovery generator vapor production ratios ranging from 0 to 3.5%. The life cycle saving economic analysis, for which the annual gas conservation is estimated with Bin method, is employed to prove the worthiness of extra expenditure. Results show that the optimum gas saving revenue is obtained at 2.8% heat recovery generator vapor production ratio with 42 kW exhaust heat recovered, and the system energy efficiency is improved from 1.78 to 1.83. The initial investment of exchanger can be paid back within 7 years and 9 000 CNY of gas saving revenue will be achieved over the 15-year life cycle of the machine. This technology can be easily implemented and present desirable economic effects, which is feasible to the development of triple-effect absorption cycles.展开更多
Drum level sloshing is the latest discovery in the application of heat recovery steam generator (HRSG) in combined cycle, and shows certain negative influence on drum level controlling. In order to improve drum level ...Drum level sloshing is the latest discovery in the application of heat recovery steam generator (HRSG) in combined cycle, and shows certain negative influence on drum level controlling. In order to improve drum level controlling, influence factors on the drum level sloshing were investigated. Firstly, drum sub-modules were developed using the method of modularization modeling, and then the model of drum level sloshing was set up as well. Experiments were carried out on the experimental rig, and the model was validated using the obtained experimental results. Dynamic simulation was made based on the model to get a 3-D graph of drum level sloshing, which shows a vivid procedure of drum level sloshing. The effect of feed-water flow rate, main-steam flow rate and heating quantity on the drum level sloshing was analyzed. The simulation results indicate that the signals with frequency higher than 0.05 Hz are that of drum level sloshing, the signals with frequency of 0.0-0.05 Hz are that of drum level trendy and "false water level", and variation of the feed-water flow rates, main-steam flow rates and heating quantities can change the frequency of drum level sloshing, i.e., the frequency of sloshing increases with the increase of feed-water flow rate, or the decrease of the main-steam flow rate and the heating quantity. This research work is fundamental to improve signal-to-noise ratio of drum level signal and precise controlling of drum level.展开更多
Reducing CO2 emissions and restraining dependence on nuclear power generation are serious concerns in the prevention of global warming since the Great East Japan Earthquake. To do so, it is necessary to use and expand...Reducing CO2 emissions and restraining dependence on nuclear power generation are serious concerns in the prevention of global warming since the Great East Japan Earthquake. To do so, it is necessary to use and expand natural renewable energy source such as solar energy and to promote energy conservation. However, in high-latitude regions, it is difficult to directly and effectively use solar power due to on insufficient amount of solar radiation. If steam can be generated from warm water at less than 373 K, it is possible to obtain steam by solar water heaters from weak solar radiation and industrial waste warm water without the consumption of any fossil fuels. In this study, the authors have been developing a system which generates steam over 423 K from warm water at less than 373 K using an adsorption heat pump with zeolite. Therefore, bench-scale equipment which generates steam continuously and the experimental results are mentioned.展开更多
基金Supported by National Natural Science Foundation of China (No. 50376044)
文摘An exhaust heat recovery generator is proposed to be integrated with conventional gas-fired triple-effect LiBr/water absorption cooling cycles to improve system energy efficiency. As a case study, simulation of the novel cycle based on promising parallel flow with cooling capacity of 1 150 kW is carried out under various heat recovery generator vapor production ratios ranging from 0 to 3.5%. The life cycle saving economic analysis, for which the annual gas conservation is estimated with Bin method, is employed to prove the worthiness of extra expenditure. Results show that the optimum gas saving revenue is obtained at 2.8% heat recovery generator vapor production ratio with 42 kW exhaust heat recovered, and the system energy efficiency is improved from 1.78 to 1.83. The initial investment of exchanger can be paid back within 7 years and 9 000 CNY of gas saving revenue will be achieved over the 15-year life cycle of the machine. This technology can be easily implemented and present desirable economic effects, which is feasible to the development of triple-effect absorption cycles.
基金Project(51276023) supported by the National Natural Science Foundation of ChinaProject(09k069) supported by the Open Project Funded by Universities Innovation Platform, Hunan Province, ChinaProject(2011GK311) supported by the Office of Science and Technology of Hunan Province, China
文摘Drum level sloshing is the latest discovery in the application of heat recovery steam generator (HRSG) in combined cycle, and shows certain negative influence on drum level controlling. In order to improve drum level controlling, influence factors on the drum level sloshing were investigated. Firstly, drum sub-modules were developed using the method of modularization modeling, and then the model of drum level sloshing was set up as well. Experiments were carried out on the experimental rig, and the model was validated using the obtained experimental results. Dynamic simulation was made based on the model to get a 3-D graph of drum level sloshing, which shows a vivid procedure of drum level sloshing. The effect of feed-water flow rate, main-steam flow rate and heating quantity on the drum level sloshing was analyzed. The simulation results indicate that the signals with frequency higher than 0.05 Hz are that of drum level sloshing, the signals with frequency of 0.0-0.05 Hz are that of drum level trendy and "false water level", and variation of the feed-water flow rates, main-steam flow rates and heating quantities can change the frequency of drum level sloshing, i.e., the frequency of sloshing increases with the increase of feed-water flow rate, or the decrease of the main-steam flow rate and the heating quantity. This research work is fundamental to improve signal-to-noise ratio of drum level signal and precise controlling of drum level.
文摘Reducing CO2 emissions and restraining dependence on nuclear power generation are serious concerns in the prevention of global warming since the Great East Japan Earthquake. To do so, it is necessary to use and expand natural renewable energy source such as solar energy and to promote energy conservation. However, in high-latitude regions, it is difficult to directly and effectively use solar power due to on insufficient amount of solar radiation. If steam can be generated from warm water at less than 373 K, it is possible to obtain steam by solar water heaters from weak solar radiation and industrial waste warm water without the consumption of any fossil fuels. In this study, the authors have been developing a system which generates steam over 423 K from warm water at less than 373 K using an adsorption heat pump with zeolite. Therefore, bench-scale equipment which generates steam continuously and the experimental results are mentioned.