660 MW等级超超临界锅炉低负荷水动力安全性分析

Low Load Hydrodynamic Safety Analysis of 660MW Ultra Supercritical Boiler

由于现代电力负荷峰谷差逐渐增大,火电必须参与调峰,不再带基本负荷。这些都使得锅炉水冷壁工质在超临界压力与亚临界压力之间不断变化,管内工质既可能为超临界压力水,也可能为汽液两相流,工质热物性变化大,尤其是30%THA工况水冷壁容易发生脉动、水冷壁多值性、停滞、动态不稳定性等问题,因此依托某660 MW超超临界锅炉低负荷工况运行时对锅炉水动力安全性进行核算,校核锅炉受热面工作的可靠性并提出提高可靠性的措施。

Due to the gradual increase of peak valley difference of modern electric power load, thermal power must participate in peak regulation and no longer carry basic load. All of these make the working medium of boiler water wall constantly changing between supercritical pressure and subcritical pressure. The working medium in the tube may be supercritical pressure water or vapor-liquid two-phase flow, and the thermal physical properties of working medium change greatly. Especially, the water wall under 30% THA condition is prone to pulsation, multi value of water wall,stagnation, dynamic instability and other problems. Therefore, this paper relies on a 660 MW ultra supercritical boiler When the boiler is operating under low load condition, the hydrodynamic safety of the boiler is checked, and the reliability of the heating surface of the boiler is checked, and the measures to improve the reliability are put forward.