【摘要】 孔流系数是孔特性研究的重要参数之一,其特性研究在工程实际中非常重要。可以由理论公式、实验数据拟合或关联式及数值模拟等方法表示。常用孔的形状可以分成普通孔(圆孔、方孔)与特殊孔(如U型孔,V型孔等)两大类,笔者对常用工艺孔孔流系数的不同研究方法及适用条件进行了综述,分析发现,孔流系数C0=F(孔形状、雷诺数Re、厚径比δ/d0)。薄壁小孔的孔流系数可以近似为0.62~0.63;厚壁孔的孔流系数可以近似为0.82;流量系数C0与流速系数CV、收缩系数ε、阻力系数ξ的关联式可以表述为简单孔孔流系数关联式为:C0=εCV,收缩系数ε=AA1c,CV=11+ξ流速系数。笔者认为,前人对特殊孔的研究相对较少,今后对孔流系数的研究应借助先进实验方法,采用数值模拟技术,拓宽研究领域和适用范围,特别是应加强对特殊孔的研究,以加快新设备的开发与利用。更多还原

【Abstract】 The character of hole flow is very important because it is one of the important parameters of this research,which can be usually expressed by theoretic formulas,charts made by datum from experiments,and simulations.The holes can be divided into two groups,special holes and common ones.In this paper,the research situation and its applied conditions of general holes met in engineering are discussed.It was found that the discharge coefficient is the function of the shape,the flow conditions,Re,δ/d₀ and other parameters.The sharp and thick circular hole flow is with the discharge coefficient of 0.62～0.63 and 0.82 respectively.The relationship among C₀、C_V、ε and ξ is as C₀=εC_V;ε=A_cA₁,C_V=11+ξ for common holes.It is pointed out that the research on the special hole flow in engineering is very limited.Further research on discharge coefficient should be made better by using modern experimental method,and combining with model simulation,in order to enlarge the use field,and stimulate the design and development of new equipments.更多还原