Uncertainty evaluation method for overall thermal performance test of combined cycle unit

Abstract

The invention discloses an uncertainty evaluation method for an overall thermal performance test of a combined cycle unit. The uncertainty evaluation method comprises the following steps: a, establishing a mathematical physical equation between heat consumption rates and output powers of an input quantity and an output quantity; b, collecting the accuracy and parameter distribution types of test instruments and meters corresponding to all input quantities in the thermal performance test of the combined cycle unit; c, performing a thermal performance test, and calculating an input quantity matrix and standard uncertainty of test data; d, calculating the standard uncertainty of the test instrument and the instrument; e, generating a random variable delta X according to the test data and thestandard uncertainty of the test instrument and the instrument, and calculating corresponding output quantities HR (X + delta X) and P (X + delta X); and f, performing repetitive calculation, ending the calculation when the repetitive calculation result meets the condition that UN-UN-1 is less than or equal to delta U0, and calculating the final test uncertainty U according to the standard deviation sigma of the probability distribution curve. The uncertainty of the performance test of the combined cycle unit can be quickly and accurately calculated, and the method can be used for guiding theperformance test of the combined cycle unit.

Description

Technical field[0001]The invention belongs to the technical field of combined cycle unit performance testing, and specifically relates to a method for evaluating the uncertainty of the overall thermal performance test of the combined cycle unit.Background technique[0002]The overall performance test of the combined cycle unit, especially the assessment test of the newly-built unit, is of great significance for the technical appraisal, performance guarantee and problems of the unit. The test uncertainty can measure test quality and test level, and is an important indicator for judging whether the test meets the relevant standards.[0003]The current source of the general uncertainty evaluation method is "The guide to the expression of uncertainty in measurement" (GUM) promulgated and implemented by ISO in 1993. GUM is a direct uncertainty analysis method. It is a mathematical reasoning method to calculate the combined standard uncertainty and expanded uncertainty through the uncertainty...

AI Technical Summary

Problems solved by technology

In the calculation process of this method, the partial derivative of each input quantity to the output quantity needs to be calculated as the sensitivity coefficient. When the input quantity and output quantity are complex nonlinear functions, the process of calculating the partial derivative becomes extremely cumbersome.

For the performance test of the combined cycle unit, the relationship between input and output is a complex nonlinear function, and the GUM method requires tedious partial derivatives

Images