两类过热器壁温分布特性的仿真研究

以一种分布式传热模型为基础,对后屏过热器和高温过热器的壁温分布特性进行了仿真研究.结果表明:这两类过热器的壁温分布特性存在较明显的差异:对于后屏过热器,随着高度方向烟温偏差的增大,各个管圈出口段壁温下降,水平段壁温显著升高;对于高温过热器,当高度方向烟温偏差较小时,壁温最高点位于尾部上升段内,且各点壁温相近;随着这一偏差的增大,壁温最高点逆工质流程向管屏下部移动.

Simulation Research on the Wall Temperature Distribution Characteristics of Two Types of Superheater

Based on a distributed model for heat transfer of superheater, a simulation research on the wall temperature distribution characteristics is performed for the rear platen superheater and high-temperature superheater. The simulation results show that there are obvious distinctions in temperature distribution characteristics between the two types of superheater. For the rear platen superheater, with the increase of gas temperature deviation along the height, the wall temperature at the outlet decreases, and the wall temperature of the horizontal part increases remarkably. While for the high-temperature superheater, when the gas temperature deviation is small along the height, the maximum wall temperature appears at the rising section of the tail part, and the wall temperatures are very close. With the increase of gas temperature deviation, the maximum wall temperature moves against the flow direction of the working substances toward the lower part of the panels.