effective velocity meaning in English
有效流速
有效声速
有效速度
Examples
- For shutters , the results show : 1 ) according to the formula p = , the theoretical value of is calculated by the effective velocity of the flow , and its engineering value is calculated by the arriving velocity of the flow , the relationship between the theoretical value of and its engineering value is 2 ) the smaller value of declining angle will result in the smaller pressure loss and smaller outlet velocities . as a result , the declining angle of 30 掳 or less is recommended in some places which need small wind velocity , such as broadcasting studio and library , and the declining angle of 45 掳 or less is recommended in places which need big wind velocity , such as cinema and office ; 3 ) the larger value of ratio between the wide of the shutter b and the space between two boards h ( b / h ) will result in the larger pressure loss and smaller outlet velocities . the range of b / h from 0 . 8 to 2 . 0 and the optimum value 1 . 2 is recommended ; 4 ) the range of b from 10 mm to 50 nun and the optimum value 40 mm is recommended ; 5 ) the proper thickness of the boards 8 of the shutters is 1 . 5 mm ; 6 ) cuneiform boards should replace the rectangle inlet boards of the shutters in order to obtain better ventilation
数值模拟采用fluent软件，计算结果用excel进行处理，通过对大量数值工况进行数值模拟计算，结果表明：对于单侧百叶风口，计算表明： 1 )对于公式p = ( ~ 2 ) 2 ，的理论计算值中定义为流体流经百叶风口内部时的速度，即有效速度，而工程上常使用流体的来流速度来计算，计算表明，的理论计算值与工程应用值的关系为( _ (理论) ) ( _ (工程) ) = 0 . 813 ； 2 )当来流速度一定时，挡板倾斜角度越小，压力损失越小、出口速度越小；因此在要求进口风速比较小的场所，如播音室、图书馆等，宜采用挡板角度30的百叶风口；在要求进口风速比较大的场所，如电影院、办公室等，百叶挡板的角度应选45 ； 3 )当来流速度一定时，百叶挡板的挡板宽度b与挡板间距h的比值b h越大，压力损失越大，出口速度越小，计算表明，鉴于压力损失、出口风速、板间形成涡流区的大小，百叶挡板的b h值取0 . 8到2 . 0之间， b h = 1 . 2为最佳值； 4 )当来流速度一定时，在计算的条件下，当百叶挡板宽度b = 40mm时，百叶挡板的阻力系数最小，考虑到涡流区等的影响，建议选用10mm b 50mm的百叶挡板；西安建筑科技大学硕士学位论文5 )百叶挡板的厚度取为1 . sinln为好; 6 )百叶挡板的入口侧可选用具有倾斜度的楔形挡板来代替矩形挡板，利用其较好的导流作用，可得到更好的出流效果。