Question

Task 8 6 Pts A so called "flow straightener" is arranged in a tube to produce a flat velocity profile, independent of the profile which is created by the flow. The straightener consist of a package of parallel-arranged thin tubes with small inner diameter, which fills out the entire cross section of the hosting tube (see fig. 1). Here a special design of the straightener is used: it consists of 50 tubes with quadratic cross section (0.025 0.025 m²) and 25 tubes with rectangular cross section (0.025 x 0.05 m²). The tubes are arranged according to a special geometrical scheme (see fig. 2). The liquid is water with a density of 1000 kg/m². The pressure difference Ap between the front and the rear side of the straightener and the length of the straightener are given in tab. 1 The entrance friction factor of the straightener tubes is 1.1 and the friction factor is 0.025, which includes the correction factor between circular and rectangular geometries. Calculate the volume flow rate. 1 2 5 L m 0.5 0.8 105 3 0.3 105 4 0.5 2.0 105 0.8 2.0 105 Ap N/m2 105 Table 1

Answer 1