Boiler secondary air damper characteristic test data processing method

Abstract

The invention discloses a boiler secondary air damper characteristic test data processing method which comprises the following steps of: dividing boiler secondary air damper characteristic test data into two groups, wherein a first group refers to test data when the opening degree of a secondary air damper is 100%, and a second group refers to test data when the opening degree of the secondary air damper is respectively a%, b%, c% and d%; processing the first group of data, thereby obtaining a hearth resistance loss coefficient; calculating resistance coefficients of the secondary air damper under each opening degree; drawing a resistance coefficient-damper opening degree relation curve; and in combination with airflow temperature and secondary air box-hearth outlet pressure difference, calculating air speed of a secondary air nozzle during heat-state operation. According to the method, the hearth resistance loss coefficient is introduced during damper characteristic test data processing, so that compared with a scheme which ignores furnace pressure loss, the scheme adopted by the method is capable of calculating the secondary air volume more accurately.

Description

technical field [0001] The invention belongs to the field of thermal energy engineering, and relates to a processing method for characteristic test data of a boiler secondary air baffle. Background technique [0002] In the stage of commissioning and commissioning of thermal power generating units or after the overhaul, the aerodynamic field test of the furnace is often carried out. Under cold conditions, the thermal operating conditions in the furnace are simulated to understand the flow characteristics of the air flow, check whether the installation angle of the burner is correct, and check the rotation. Whether the air flow is deflected, edged or brushed, provides the necessary basis for thermal operation and combustion adjustment; the aerodynamic field test of the furnace includes three stages. Resistance balance, the second is the secondary air baffle characteristic test, the third is to adjust the furnace air volume ratio to enter the self-modeling state, and enter the...

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Problems solved by technology

[0004] At present, the test data of the baffle characteristics are often drawn as the change curve of the nozzle wind speed (or air volume) with the baffle opening for reference in adjusting the wind speed. , "Experimental Research on Cold State Aerodynamic Field of 1913t / h Supercritical Square Tangential Boiler", "Experimental Research on Cold State Aerodynamic Field of 2023th Subcritical Four Corner Tangential Boiler" and other documents have carried out similar processing on the test data; Although the opening of the secondary air baffle that should be maintained in the third stage of the aerodynamic field test can be quickly determined according to the relationship curve between the nozzle wind speed and the baffle opening, but due to the change of the airflow density and the pressure difference between the bellows and the furnace outlet, the curve Cannot be used for hot running adjustments

[0005] "Application of Boiler Cold State Aerodynamic Field Test Data in Thermal State Adjustment", "Corner Tangent Round Boiler Cold State Aerodynamic Field Test", "Relationship Research on Furnace Bellows Pressure, Damper Opening and Secondary Wind Speed" and other documents, After further processing the test data of the characteristics of the secondary air baffle, the resistance coefficient of the baffle is obtained, and the resistance coefficient is applied to the calculation of the air volume in the hot state. The pressure drop to the outlet of the furnace is equal to the pressure drop from the bellows to the secondary air nozzle; using this assumption, the nozzle wind speed obtained will be greater than the actual value; in order to improve the calculation accuracy of the nozzle wind speed, the literature "Mathematical model and measurement of boiler secondary air nozzle flow Method Discussion" provides a solution to directly measure the pressure difference between the bellows and the secondary air nozzle, bypassing the problem of furnace pressure drop; however, due to the large number of secondary air nozzles, this solution requires a large number of new pressure measuring points, which increases the Test costs, and these new measuring points need to invest a lot of operation and maintenance costs in actual production

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