基于数值模拟方法的多孔板流阻特性与流动机理研究

Study on Flow Resistance Characteristics and Flow Mechanism of Perforated Plate Based on Numerical Simulation Method

多孔板作为节流装置广泛应用于工业界,明确多孔板流阻特性的主要影响因素和流动机理对该类装置的工程应用具有重大意义。针对影响多孔板流阻特性的结构参数,以内流直管道的多孔板为研究对象,通过数值模拟方法分析了开孔率、深径比以及小孔数量对多孔板前后压降系数的影响机理,重点讨论流动的机理特征。结果表明:开孔率对压降的影响比较明显,开孔率越小,压降值越大;相比开孔率对压降值的影响,深径比对压降的影响不大;在同样的开孔率下,多孔板的流阻更大,但是其可以产生更快的压力恢复;小孔数量为5时,小孔下游涡量紊乱性明显,涡间干扰相较单孔更强。

Perforated plates are widely used in industry as a throttling device.It is important to identify the main factors and flow mechanism of perforated plate flow resistance characteristics for the engineering application.The perforated plate of straight pipeline is the research object.Through the numerical simulation method,the influence mechanism of the porosity,the thickness to diameter ratio and the number of small holes on the pressure drop coefficient of perforated plate is analyzed,and the flow mechanism characteristics are mainly discussed in this paper.The results show that the effect of porosity on pressure drop is obvious.The smaller the porosity is,the larger the pressure drop is.The thickness to diameter ratio has little effect on pressure drop.Under the same porosity,the flow resistance of the perforated plate is greater,but it can produce faster pressure recovery.When the number of small holes is 5,the downstream vorticity disorder of small holes is obvious,and the interference between vortices is stronger than that of single holes.