汽轮机通流部分面积评价本科.docVIP

摘 要 汽轮机通流部分是机组能量转换的关键部位，通流部分一旦发生故障将对汽轮机组运行的安全性与经济性产生重要影响。所以，对汽轮机通流部分故障分析和诊断是十分必要的。本论文在参考大量国内外文献的基础上，对汽轮机通流部分的的通流特性进行了细致的研究。 本文首先从影响汽轮机相对内效率的因素出发，论证了影响汽轮机相对内效率的因素以及级内各项损失的原因，并对漏汽损失在原理上进行了理论分析，并给出了漏汽损失的公式计算分析。 以弗留格尔公式为基础，经过推导演绎，提出了汽轮机级组特征通流面积的新概念，给出了明确的解析式。通过具体实例验证了级组特征通流面积的精度，并指出了级组特征通流面积在机组运行分析、变工况计算、监测与诊断等方面的应用途径。在建立机组通流部分的精确热力性能档案时，除了考虑级组的特征通流面积及其相对于设计工况的偏差率外，还考虑了级组的相对内效率和级组内功率。 对汽轮机通流部分结垢现象，从实际出发给予分析，并对汽轮机结垢后，对汽轮机功率和效率的影响从理论上进行了论证。最后，还对结垢后汽轮机前后压力比的变化进行了分析。 本论文紧密结合电厂汽轮机通流部分的实际情况进行分析研究。研究成果的应用，可以较好的解决以前单纯的以级组相对内效率为判据所带来的诊断结果受回热系统运行情况和机组“重热现象”影响的弊端，也能为电厂汽轮机通流部分运行监测、故障诊断以及机组的变工况计算提供良好的理论依据。 关键字：汽轮机；通流部分；特征通流面积；结垢 Title Turbine flow passage area of Evaluation Method Abstract The flow passage of steam turbine is the key part of a unit for energy conversion. Once faults occur in the flow passage，it will have great impact on the security and economy of a running turbine.Thus，it is necessary to study on fault analysis and fault diagnosis of the flow passage of steam turbine. Referring to plenty of literatures both in China and abroad，this paper has carried out detailed research on flow characteristic of the flow passage of steam turbine.In this paper，starting from the influence factors of relative internal efficiency for steam turbines，demonstrates the influence factors of relative internal efficiency of steam turbines and the reasons for the loss in the level and leakage losses in the theoretical analysis on the principle and calculation and analysis of leakage loss of a formula are given. Based on Flugel formula，a new concept of characteristic flow area of steam turbines was presented by derivation and deduction，and the definite analytical expression of the characteristic flow area was given in this paper. An illustrative example is provided to verify the precision of characteristic flow area，and the appliedaccuracy thermal performance file of flow passage the characteridtic flow area of steam turbine and its rate of