Question

solve thes problem

how thes equation come from slope for

solution

EXAMPLE 5.10 The pressure drop due to friction for flow in a long smooth pipe is a function of average flow velocity, density, viscosity, and pipe length and diameter: Ap fcn V, p, , L, D). We wish to know how ΔΡ varies with V. (a) Use the pi theorem to rewrite this function in s and Similarity dimensionless form. (b) Then plot this function, using the following data for three pipes and three fluids V, m/s* 1.06 2.12 3.54 0.88 1.77 2.74 0.20 0.39 0.67 D, cm 1., m Ap, Pa p, kg/m μ, kg/(m . s) Im 0.3 0.6 4,680 22.300 70,800 2,080 10.500 30.400 540 2.480 9,600 1.0 1.0 2.92 E-4 2.92 E-4 2.92 E-4t 0.0010 0.00104 0.00 1 야 1.56 E-38 1.56 E-38 1.56 E-38 680+ 2.0 2.0 2.0 3.0 3.0 7.0 9.0 4.0 6.0 8.0 680 680 998 998 998 3.550 3.550 13,550s 2.0 0.5 4.0 Gasoline. Water sMercury (c) Suppose it is further known that Ap is proportional to L (which is quite true for long pipes with well-rounded entrances). Use this information to simplify and improve the pi theorem formulation. Plot the dimensionless data in this improved manner and comment on the results. power-law function: ex-ose) D' pVD 1.75 0.155 Ans. (c)

Answer 1

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