广州中电荔新锅炉烟道降阻分析与优化改造

Resistance-reduction and Optimization for Boiler Flue in Guangzhou ZDLX Power Co.,Ltd.

为解决广州中电荔新机组投产后机组运行至满负荷附近时引风机出口烟道阻力异常高的问题,在对引风机出口处烟道流速测试分析的基础上,以引风机出口到增压风机入口烟道段为例,利用Gambit软件按烟道实际尺寸建立了烟道的数学模型。该模型采用SIMPLE算法,实现压力和速度的耦合求解;模型模拟和实测获得的压力损失结果接近,验证该数学模型的合理性。利用该模型对改造前烟道模拟,发现扩压拐弯段和增压风机入口段的压损比较严重,认为是烟道几何形状不合理所导致。为此,通过加装弧段导流板、隔流板、斜板等措施找到降阻最佳方案并对扩压拐弯段和增压风机入口段进行改造,改造后流场模拟表明这两段流速明显下降,阻力得以降低。

For solving problem of abnormal high fuel resistance at the exit of induced draft fan when the unit of Guangzhou ZDLX Co.,Ltd.running with almost full load,this paper analyzes fuel flow velocity testing at the exit of induced draft fan.Taking fuel section from the exit of induced draft fan to entrance of the booster fan as example,it discusses establish-ment of mathematical model for the fuel by using Gambit software and according to actual size of the fuel.This model uses SIMPLE algorithm to realize coupling solution to pressure and speed.Pressure loss results of model simulation and actual measurement are close to each other which verifies reasonability of this mathematical model.Fuel simulation before optimi-zation reform was conducted by using this model,pressure loss of diffusion turning section and entrance section of the boost-er fan was found serious which was considered to be caused by unreasonable geometrical shape of the fuel.Therefore,by means of installing arc guide plate,isolating plate,cantboard and so on,optimal resistance-reduction scheme was found and optimization on diffusion turning section and entrance section of the booster fan was carried on.Flow field simulation after optimization indicated that flow velocity of these two sections declined obviously and resistance reduced.