摘要
空冷机组的背压影响机组建设投资和运行费用,因此,背压是空冷汽轮机设计、制造的重要参数。影响其背压的主要因素有:大气环境温度、空冷初始温差、凝汽器的端差。确定环境温度通常采用6000h法和+5℃以上温度平均法。机组存在最佳的初始温差,使其综合技术经济性最好。末级叶片设计时,应考虑适应排气点的排气面积、叶片承受容积流量剧烈变化的能力、叶片中的应力在适当水平、叶片有良好的可膨胀性、叶片采用加强型和高机械阻尼的结构。
The backprcssure of the air-cooled units has an influence on construction investment and operation cost of the units and so the backpressure is an important parameter of design and manufacture for the air-cooled turbines. The major factors effecting on the backpressure include atmospheric environment temperature, primary temperature difference of air-cooling, end difference of condensers. To determine the environment temperature is usually by means of 6 000 h and above ＋ 5℃ temperature average. The optimum primary temperature difference existing for the unit will make its best compreheusve eeonomie and technical performance. In design of the last hlade the consideration should be given to the exhaust area at the exhaust point, capability of the hlades to hear severe variation of volume flow, proper stress on the blades, good expansihility of the blades. The hlades should consist of enhanced and high mechanical damping structures.
出处
《电力建设》
2005年第8期1-3,共3页
Electric Power Construction
关键词
空冷机组
背压
末级叶片
参数选取
air-cooled unit
back pressure
last stage blade
parameter selection
