CFD模拟循环水排净管线防冻问题

CFD Simulation of Anti-freezing Problem of Circulating Water Drainage Pipeline

利用CFD软件初步模拟分析循环水排净管线防冻问题,研究循环水排净管线长度、循环水流速、室外温度、风速、保温厚度对排净管线轴向温度分布的影响。研究结果如下:随着排净管线长度的增加,排净管线轴向温度先缓慢降低,当排净管线长度大于循环水流动可影响的长度后,其温度随其长度的增加快速减小;循环水流速越大,其影响的排净管线区域越大,排净管线温度开始快速降低的点越靠近排净管线末端,且其温度下降的速率越慢;室外温度越高,循环水排净管线轴向温度降低得越慢,但排净管轴向温度开始明显降低的点与室外温度无关;循环水排净管线包裹保温材料具有明显的防冻作用,包裹保温材料后的循环水管线,受室外温度,风速的影响都将变小。但循环水管线不用时,排净管线的水一定要排空。模拟结果为北方寒冷地区循环水管线的防冻设计提供技术指导依据。

In the paper,the anti-freezing problem of circulating water drainage pipeline was preliminatively simulated and analyzed by using CFD software,and the influence of circulating water drainage pipeline length,circulating water velocity,outdoor temperature,wind speed and insulation thickness on the axial temperature distribution of the drainage pipe line was studied.The results are as follows:with the increase of the length of the clean pipeline,the axial temperature of the clean pipeline decreases slowly at first.When the length of the clean pipeline is greater than the length that can be influenced by circulating water flow,the temperature decreases rapidly with the increase of the length.The larger the flow rate of circulating water is,the larger the drainage area is affected.The closer the point where the temperature of the drainage line begins to decrease rapidly is to the end of the drainage line,and the slower the rate of temperature decrease is.The higher the outdoor temperature is,the slower the axial temperature of the circulating water drainage pipe decreases,but the point at which the axial temperature of the drainage pipe decreases obviously has nothing to do with the outdoor temperature.The circulating water drainage pipeline wrapped with insulation material has obvious anti-freezing effect,and the circulating water pipeline wrapped with insulation material will be less affected by outdoor temperature and wind speed.But when the circulating water pipeline is not used,the water of the clean pipeline must be emptied.The simulation results provide technical guidance for the antifreezing design of circulating water pipelines in cold areas in north China.