全尺度压缩空气泡沫输运管道压力分布试验

Experimental study on pressure distribution in full-scale compressed air foam transport pipeline

为有效提升压缩空气泡沫输运能力,更好地应对换流站火灾,开展699、406、261 m全尺度压缩空气泡沫输运管道压力分布试验研究;分析组合管道复杂程度和管道长度对压缩空气泡沫输运管道内压力的影响;采用当量阻力长度等效静压损失和局部压力损失的影响,并引入综合当量阻力系数,构建适用于工程应用的压力损失经验关系式。结果表明:在压缩空气泡沫输运阶段,管道进出口压力随时间增加先迅速升高,后趋于稳定,达到稳定状态所用时间与管长和管道复杂程度成正比,在压缩空气泡沫停止输运后,管道内压力骤降;组合管道的复杂程度不同,导致压缩空气泡沫管道内局部压力随输送距离增加,呈现非线性减小的变化趋势;得到压力损失与当量阻力长度的经验关系式,该式可用于预测管径DN50~DN200、管长1 000 m范围内的压降变化。

To effectively enhance the transportation capacity of compressed air foam and better address the fire hazards in converter stations,experimental research was conducted on pressure distribution using full-scale compressed air foam transport pipelines of 699,406 and 261 m as examples.Furthermore,the equivalent resistance length method was proposed to consider static pressure loss and local pressure loss,and a comprehensive equivalent resistance coefficient was introduced.An empirical pressure loss relationship suitable for engineering applications was developed.The results indicate that during the compressed air foam transport phase,the pipeline inlet and outlet pressures rapidly increase with time before stabilizing.The time required to reach a steady state is proportional to the length and complexity of the pipeline.After foam transport ceases,the pressure within the pipeline drops sharply.The complexity of the pipeline configuration leads to a nonlinear decrease in local pressure with increasing transport distance.Finally,an empirical relationship between the pressure loss and the equivalent resistance length has been obtained,which can be used to predict pressure drop variations for pipe diameters ranging from DN50 to DN200 and pipeline lengths up to 1000 m.