工业锅炉热效率测试不确定度分析

Uncertainty Analysis of Thermal Efficiency Testing for Industrial Boiler

为描述锅炉热效率测试结果的可信程度,需对测量结果进行测量不确定度分析,测量不确定度表征测量结果的可信程度。本文以燃煤热水锅炉正平衡测试不确定度分析为研究内容,介绍了正平衡测试不确定度分析的基本原理,包括分析模型的建立,评定方法的选择,合成标准不确定度及扩展不确定度的计算,给出了一台燃煤热水锅炉正平衡热效率不确定度的分析模型及评定实例。评定结果表明,影响燃煤热水锅炉正平衡测试结果不确定度的因素主要有燃料消耗量、出水温度、进水温度、循环水流量、燃煤热值、循环水密度等,在测试中要着重减小这些参数的不确定度。

In order to describe the confidence level of thermal efficiency test result for industrial boil- er, Uncertainty analysis should be needed, it characterized the reliability of the measurement results. This paper introduced the basic theory of uncertainty analysis, include the establishment of uncertain- ty analysis model, the assessment method of uncertainty in type A or B, and the calculation of normal combined uncertainty and extended uncertainty. Then, a coal -fired hot -water boiler is employed as an example for illustrate the proposed method. The calculated results state clearly that the main affecting factors of uncertainty for the measured values are Coal consumption, outlet water tempera- ture,inlet water temperature, water flow rate, coal＇ s Calorific value, and water density. Therefore, it is necessary to reduce the uncertainty of these parameters in testing.