Double-channel heater drain cooling section inlet structure and design method

Abstract

The invention discloses a double-channel heater drain cooling section inlet structure and a design method. A traditional heater siphon inlet is modified and optimally designed, a newly designed separation partition plate is introduced to form a siphon section dual-channel inlet, meanwhile, a downstream side drain cooling end plate extends to flow, and two channels further form high and low water level channel inlets. A series of newly-designed turbulent flow grids are evenly embedded in the inner end faces of upstream and downstream drain cooling end plates and the inner and outer end faces of the separation partition plate. In addition, a siphon section inlet is processed into a tapered molded line inlet channel, and the area scaling ratio of an inlet and outlet of a tapered channel and the starting expansion position of a tapered line can be determined through numerical simulation optimization according to the optimal running water level of a drain cooling section as an optimization target. The modeling design is realized by changing the coordinates of the control points on a control molded line to adjust the curvature distribution of the control molded line.

Description

technical field [0001] The invention belongs to the field of steam turbine power generation, and in particular relates to an inlet structure and a design method of a hydrophobic cooling section of a double-channel heater. Background technique [0002] At present, the regenerative cycle is widely used in the system design of large thermal power plants, and the regenerative cycle is realized by configuring the feed water heater. The feedwater heater is an important equipment to improve the economy of thermal power plants. According to the different steam-water heat exchange methods in the feedwater heater, it is usually divided into superheating section, saturated section and cooling section in structure. The superheated section of the heater uses the sensible heat of the superheated extraction steam of the steam turbine stage to heat the feed water in the shaped pipe. After the steam is deflected in multiple ways through the partition, the superheated steam will be cooled to ...

AI Technical Summary

Problems solved by technology

Currently affected by factors such as power peak regulation, the operating conditions of the generator set are complex. The heater must not only operate under rated conditions, but may also be affected by various abnormal conditions. Therefore, the water level of the heater will fluctuate significantly. Fluctuation phenomenon

The commonly used cold-draining section of the heater is a single-channel planar end wall design. When the working condition changes and the water level of the heater fluctuates, the equilibrium state of the siphon structure is easily destroyed, and part of the steam in the saturated section will enter the cold-draining section. , which leads to the occurrence of vapor-liquid two-phase flow phenomenon, which increases the difference between the hydrophobic ends of the heater, which in turn intensifies the erosion of the tube wall of the next stage heater, thus making the tube wall thinner, and in severe cases, safety accidents such as tube bursts occur

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