700-DEG-C boiler water wall arrangement structure capable of inhibiting negative flow response characteristics

Abstract

The invention discloses a 700-DEG-C boiler water wall arrangement structure capable of inhibiting negative flow response characteristics. The 700-DEG-C boiler water wall arrangement structure comprises water wall tube inlets, water wall tube outlets, a high heat load area water wall, low heat load area water walls, high heat load area water wall tubes, high heat load area water wall fins, low heatload area water wall tubes, low heat load area water wall fins and low heat load area water wall tube inlet throttle rings. Through the comprehensive consideration of the negative flow response characteristics of an ultra-supercritical boiler water wall and the strict restrictions of a 700-DEG-C boiler to the wall temperature deviation, the tubes of relatively small tube diameters are arranged ina high heat load area, and meanwhile, the tubes of relatively large tube diameters are arranged in low heat load areas and equipped with the inlet throttle rings; and through the structural arrangement and the design of resistance characteristics, the mass velocity of the high heat load area water wall tubes is relatively high, the mass velocity of the low heat load area water wall tubes is relatively low, the wall temperature deviation caused by the negative flow response characteristics is effectively inhibited, and the water wall local overtemperature risk of the 700-DEG-C boiler is remarkably reduced.

Description

technical field [0001] The invention relates to the technical field of high-efficiency power generation, in particular to an arrangement structure of a water-cooled wall of a 700°C boiler that suppresses negative flow response characteristics. Background technique [0002] 700℃ ultra-supercritical power generation technology is one of the important technical directions for efficient power generation in the future. In order to pursue higher efficiency, the United States, Japan, and Europe have successively carried out research on ultra-supercritical 700°C power generation technology since the 1980s, focusing on the development of high-temperature components. Since the late 1990s, Europe, Japan, the United States, India and other countries and regions have successively launched 700 ℃ ultra-supercritical power generation technology research programs, such as the European AD-700 and subsequent series programs, the US USC program, Japan’s A-USC plan, India 700°C technology devel...

AI Technical Summary

Problems solved by technology

However, for ultra-supercritical boilers of 700°C grade, the wall temperature level of boiler water-cooled walls is higher, and the wall temperature deviation caused by negative flow response characteristics is more serious. Taking a Π-type 700°C ultra-supercritical boiler as an example, its full load The wall temperature at the outlet of the water cooling wall can reach 540°C-630°C, which greatly increases the risk of local overheating of the cold wall

For ultra-supercritical boilers at 700°C, simply relying on the arrangement of throttling tube coils cannot effectively suppress the flow and wall temperature deviation caused by negative flow response characteristics.

[0005] However, it can be seen from the public literature that although there have been some studies on the hydrodynamics and wall temperature calculation of 700 °C ultra-supercritical boilers, how to effectively solve the wall temperature deviation caused by the negative flow response characteristics is rarely seen.

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