報告書番号

M01

タイトル（和文）

発電用大型ガスタービン初段動翼を対象とした温度解析技術の開発

タイトル（英文）

Development of numerical temperature analysis using CFD for 1st stage rotor blade of gas turbine for power generation

概要 （図表や脚注は「報告書全文」に掲載しております）

今日、ガスタービンを用いた複合発電は、重要な位置づけにある一方で保守コストが高く、電力各社はコスト低減の必要性に迫られている。翼寿命の最大の支配要因は温度分布であり、寿命評価や信頼性評価に対する温度把握は重要であるが、GT運転中の動翼温度分布を、長時間信頼性を確保しつつ精度良く計測することは、技術的に極めて困難である。本報告では、適切な保守により大きなコスト低減が期待できる初段動翼を対象に、実測が困難な翼温度を寿命評価に適用可能な精度で推定できる、翼周り対流熱伝達-翼構造材熱伝導-内部冷却を連成させて解く数値解析技術を構築し、1100℃級ならびに1300℃級初段動翼温度分布や翼内外の熱流動特性を解析的に明らかにした。本成果の活用により、負荷変動など過渡運転状態における翼温度分布推定が可能となり、熱疲労損傷評価に不可欠な起動・停止時の時系列的な3次元翼温度分布を求めることを可能とした。

概要 （英文）

Introduction of combined cycle power generation facility with gas turbines burning liquefied natural gas is promoted as main facility in thermal power generation. The plant have some merits that a start up, a shut down and load adjustment are easy, and the efficiency is high, and exhaust gas is clean. On the other hand, because of an expensive maintenance cost of first stage rotor blade which is a main component of GT, establishment of the maintenance judgment criteria technically that it is reasonable for users is expected. Therefore it is necessary to establish life evaluation technology of precision in accuracy, and it is indispensable to predict temperature distribution of the parts. The main factors which has an influence on life of a blade is temperature distribution, and it is important that temperature distribution is grasped for life and reliability evaluation. However, it is extremely difficult technically precision is good while getting reliability for a long time, and to measure for the temperature distribution in GT operating. In addition, because of complicated blade shape and heat transfer of the blade inside and outside, a highly precise estimate method by analysis is not developed.Objectives of this study builds the numerical analysis technique that can predict blade temperature accurately that can apply to life evaluation for a blade, and it is to clarify blade temperature distribution of a blade.Main results are as follows.1. Construction of conjugate analysis methodFor 1100 ℃ class first stage rotor blade having multi-hall type cooling pass and 1300 ℃ class first stage rotor blade having serpentine cooling pass installed angled lib, I untied blade circumference combustion gas flow convection heat transfer by Computational Fluid Dynamics, blade structure materials heat conduction, blade inside cooling simultaneously and built thermal conjugate analysis method which demanded a solution of the whole heat flow ground and got spiritual awakening equal to or less than it.2. Inspection of analysis precisionThe high temperature domain of blade surface temperature by numerical simulation coped well with the area which erosion produced by the high temperature oxidation in an actual blade. In addition, the result by simulation agreed with blade surface temperature estimated by materials organization of an actual blade well, and I was equal to or less than 20 ℃ that were a precision aim in life evaluation. 3. Practical use of this numerical simulation technologyParametric evaluations to blade temperature for unknown factors in GT operating condition, combustion gas temperature distribution or cooling air mass flow rate, enable by using the simulation technique. In addition, 3 dimensions of blade temperature distribution of chronological order in start up and shut down conditions which are necessary to be indispensable for thermal fatigue damage evaluation were enabled.

報告者

キーワード