知识与财富的链接
选取了Spalart-Allmaras湍流模型,对Re＜5500时管路中突然扩大的局部水头损失进行了数值模拟.计算结果表明:模拟得到的测压管水头与试验值吻合较好,用断面平均速度计算速度水头时,若取动能修正系数为1.0,则会使局部水头损失的计算值较实际值偏小,速度水头计算方法的影响远大于突然扩大管路的沿程损失对局部水头损失系数的影响.
Using Spalart-Allmaras turbulence model, local head loss of sudden expansion in pipe was simulated when Re was less than 5500. The results showed that the simulated piezometric head agreed well with the test. The simulated coefficient of local head loss was lower than actual value when velocity head was calculated with the average velocity of pipe section and the kinetic energy revise factor was 1.0. The influence of kinetic energy computation method was greater than that of the friction head loss occurred at the sudden expansion pipe on local head loss.
