共查询到17条相似文献,搜索用时 93 毫秒
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根据我国西北某地区的典型环境温度对600MW直接空冷机组的低压末叶片进行优化,得到合理的低压排汽面积,同时根据末级叶片的设计特点对其变工况特性进行分析,从而对620mm末叶片的变工况性能有一定了解。分析结果表明,设计背压为15kPa.a时,末叶片采用620mm比较合适;采用专用强化叶型、控制反动度、控制攻角等方法的620mm末叶片可以有效保证空冷机组变工况安全高效运行。 相似文献
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直接空冷600MW汽轮机排汽装置的结构、安装与运行 总被引:3,自引:1,他引:3
对直接空冷600MW机组排汽装置的结构特点、安装与试验要求、方法及运行进行了论述,让读者对排汽装置有比较全面的了解,对电厂的现场安装、试验及运行起指导作用。 相似文献
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The utilization of sensible waste heat such as flue gas and industrial surplus heat is essential for energy saving. Supercritical CO2 power generation cycle is a promising way to be used in this field. In this paper, a new supercritical CO2 Rankine cycle coupled with an absorption refrigeration cycle is proposed, which consists of a reheating supercritical CO2 cycle, a mixed-effect Li Br-H2O absorption refrigeration cycle and solar subsystem including evacuated-t... 相似文献
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改进型200MW汽轮机及大型空冷汽轮机的不断投产,为200MW间接空冷汽轮机改造提供了技术储备。末级叶片的优化设计是发展空冷机组重要条件之一,正是由于选择了合适的末级叶片,对丰镇电厂的机组改造取得了成功。 相似文献
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通过分析轻型汽车发动机台架实验用排气装置的现状,并指出缺点和不足,提出改进方案,设计一种适用多类型轻型汽车发动机台架实验的新型排气装置,在x,y,z,x,y,z六个方向有一定自由度和伸缩空间,这样解决在安装过程的空间干涉问题,达到一机多用,减少研发与测试成本并可缩短研发周期,并在发动机台架下与传统排气装置进行了发动机外特性对比,两种排气装置的实验结果基本一致,证明新型排气装置是可行的。 相似文献
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As a renewable source, solar energy has received more and more attention in recent years. Solar energy can readily provide heat efficiently within the temperature range of 70–100°C. For the utilization of this energy source, a cascading cycle was designed and was discussed. An organic Rankine cycle (ORC) and an adsorption refrigeration cycle were combined to provide the first- and second-stage energy conversion cycle, respectively. In the analysis, R600 was used as the working fluid for the ORC and a silica gel–water working pair was analyzed for the adsorption refrigeration cycle. The energy efficiency for electrical generation and refrigeration, as well as the exergy efficiency of the cascading cycle, was assessed. For an environmental temperature of 30°C and a refrigeration temperature of 12°C, the results showed that typically 1 kW of electricity and 6.3 kW of refrigeration could be generated from approximately 15 kW heating power. The electricity generation efficiency was between 0.1 and 0.15, while the refrigeration coefficient of performance was approximately 0.8. The exergy efficiency was found to be between 0.84 and 0.89 and between 0.32 and 0.46 for the single ORC and adsorption refrigeration cycle, respectively. The overall exergy efficiency was between 0.56 and 0.74. 相似文献
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《传热工程》2013,34(6):71-78
A new refrigeration system that uses a specially designed finned plate heat exchanger and works with zeolite and methanol is proposed. The integration of heat transfer and adsorption via a finned surface coated with zeolite CBV 901 and the use of a connected, twin active bed system to enable heat recuperation are novel features. The thermophysical properties of zeolite and methanol were first studied with the intention of designing a high performance heat exchanger (generator) for the adsorption refrigeration system. Here, the major problem is related to poor conductivity at the interface between the heat exchanger and the zeolite. The adsorbent must be heated (desorption phase) and then cooled (adsorption phase) back to ambient temperature in order to complete a thermodynamic cycle. To manufacture a sufficiently small system, there must be high rates of heat transfer in and out of the adsorbent. Therefore, the surface of the heat exchanger is finned in order to increase the heat transfer area (the fins are coated with 2 mm layer of specially prepared zeolite paste). The following characteristics were estimated from initial calculation: heating temperature, 120°C; outside tube temperature, 119.6°C; middle fin temperature, 117°C; and coated layer of zeolite paste temperature, 115.3°C. The mathematical code developed to calculate the effects of operating conditions and the Coefficient of Performance (COP) was presented at HPC 2001 in Paris. It is based on the Dubinin-Astakhov equation and thermodynamic analyses. The results obtained shows that 0.535 is the COP for a single bed and 0.925 for a double bed. 相似文献
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AbstractIn this paper, the performance of an organic Rankine cycle (ORC) power generating system operating with refrigerant R245fa was investigated when heat source temperature was below 200?°C. It was found the system thermal efficiency increased but the exergy efficiency of the evaporator decreased with the increase of the heat source temperature. It was also obtained that the exergy efficiency of the evaporator could reach70% when the heat source temperature was 80?°C, which was high enough to prove that the transformation efficiency between the waste heat and the electricity power was ideal. In the simulation model, the area of different parts of the heat exchanger were considered to be varied, flow rate of the waste heat and working medium, the system thermal and exergy efficiency of the evaporator were respectively calculated, the different parameter change regarding the performance influences of the ORC system were simulated. The results can be considered as a reference to research on the design of ORC power generating systems and heat exchangers. 相似文献