蒸汽发生器管板二次侧表面温度场瞬态计算

Transient Thermal-hydraulic Analysis of Secondary Side Fluid on the Tubesheet's Upper Surface in the Steam Generator

蒸汽发生器管板二次侧表面温度场瞬态分析用于得到瞬态工况下管板二次侧附近流体的温度场分布,为管板的疲劳断裂分析提供输入数据。通过对法国管板二次侧表面温度场瞬态分析软件MYRTE的研究,在掌握软件建模和分析方法基础上,采用FLUENT实现管板二次侧流体温度场的瞬态计算。通过在控制方程中添加附加的质量源项和能量源项建立了二次侧流场的计算模型。质量源项中添加通过流量分配板流失的质量;能量源项中添加通过流量分配板的焓通量和来自一次侧的释热。计算得到的二次侧流体区域速度场和温度场分布与MYRTE计算结果符合较好,二次侧流体温度从入口至管板中心处是缓慢升高的,管板中心处加热较为明显。同时绘制出二次侧流体温度随时间变化的曲线图,可以为管板的疲劳断裂分析提供输入参数。

MYRTE is a specialized software developed by France that be used for the transient thermal-hydraulic analysis of secondary side fluid on the tubesheet＇s upper surface in steam generator. Temperature distribution acquired can be used as the input for the fatigue analysis of tubesheet. CFD simulation of temperature distribution on the tubesheet＇s secondary side upper surface using FLUENT is conducted based on the MYRTE method. Additional mass and energy source terms are appended to the mass and energy conservative equations, respectively. The additional mass source contains the mass loss through the flow distribution plate; the additional energy source includes the heat transfer from the tubesheet and tube bundles as well as energy loss through theflow distribution plate. Velocity distribution, temperature distributions and the temperature-time curve of the secondary side fluid are given. The results obtained from FLUENT agree well with those from MYRTE. The secondary side fluid temperature increases gradually from the inlet to the center of tubesheet. Heating efficiency is more distinct in area surrounding the tubesheet center. The temperature-time curve could provide input for the fatigue analysis of the tubesheet.