7.7 Problems. b) Same question for a liquid with a viscosity index. ν=10-5 m 2 /s. c) Same question for a liquid with a viscosity index.

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1 7.7 Problems Problem 7.: horizontal pipeline has a diameter of 0. m. Water is pumped through this pipeline with a mean velocity V=.5 m/sec. Kinematic viscosity index of water ν=0-6 m /sec. Roughness of the boundary a= m. a) What difference in head can be read from two manometers that are connected to the pipe and of which the distance between the points of connection equals to 00 m. b) Same question for a liquid with a viscosity index. ν=0-5 m /s c) Same question for a liquid with a viscosity index. ν=0-4 m /s Problem 7.: In a welded steel oil line (diameter 0.6m), pumps are spaced 0 km apart. The pumps are working a difference in pressure head of 5 m oil column. alculate the discharge. ensity of the oil is ρ=800 kg/m, kinematic viscosity is ν=0-4 m /s, boundary roughness is a=5 0-5 m. In the course of time, the roughness of the pipe (expressed in terms of roughness length will grow 0 times the original value. Will the discharge be influenced by this? If so, how much (in %) will the reduction (approximate) be? Problem 7.: Find the discharge of the pipe system shown in Fig.p7. and if the diameter of the system is converted into φ50 mm find the length of the pipe of the system. (K=0.5) (K=8) 7 m (K=0.7) E (K=.0) G (K=0.7) F (K=0.5) (K=6) H sayaç K (K=0.5) (K=) I (K=0.5) M (K=) N Figure p

2 Problem 7.4: fluid with a kinematic viscosity ν=5 0-7 m /s flows in the pipe system in Fig. p7.. The roughness of the pipe is k=0.00 m and the minor head loss coefficients of the system are known as K dar =0. K g =0.05. Find the discharge of the system by using Moody diagram. (0) Enerji Yatayi h g E.Ç. h m.ç. h dar () h x Ø00 mm =4m V /g Ø75mm =m 0 () Figure p7. Problem 7.5: Water flows from the reservoir to reservoir in the Fig. p7.. The elevation difference between the reservoirs is =5.00 m. Find the discharge. raw the energy and hydraulic grade line. (g=0 m/s, ν=0-6 m /s) K g = / g+ d dar E.Ç.Ç(P.Ç) gen ç =5m =6 m = m K ç =.0 K =0. d =0.5 m - k=0 m K dar=0.4 =0. m - k=0 m K d=0. ı =8.00 m =5.00 m ı =.00 m Figure p7. Problem 7.6: fluid is pumped from a pressurized tank with a pump that is placed 4.5 m higher elevation from the fluid surface of the pressurized tank to an open tank m below the fluid surface of the pressurized tank. If the pump adds.5 kw to the system determine the discharge and the pressure at point. If the vaporization pressure of the fluid is N/cm (absolute pressure), show if the fluid evaporate or not at this point. 7-79

3 Pompa 4.5 m P E 0.5 m 0.5 m 0.5 m civa v 0 φ 50 mm λ=0.05 H E K=0.5 5 m φ 00 mm =60 m λ=0.0 K= m F γ=8700 N/m v 0 Figure p7.4 Problem 7.7: The discharge from the reservoir to reservoir is 400 lt/s in Fig. p7.5. The pressure at the outlet of the turbine E is 5 mwc. Find the power which could be obtained from the turbine and draw the energy grade line of the system. =000 m =500 mm λ =0.0 E.Ç 8 =500 m =500 mm λ = =000 m 4 =600 mm λ 4 =0.0 =500 m =600 mm λ =0.0 E 00 Figure p7.5 Problem 7.8: The fluid flows from reservoirs () and () to valve at M. The Manning roughness coefficient for the pipes are n=0.04. a) The piezometer height at M is m, b) nd when the valve is opened at M determine the discharge. c) raw the energy grade line for both cases. 7-80

4 5 m E.Ç (a hali) m 09 m E.Ç (b hali) φ 400 mm =500 m 00 m φ 00 mm =00 m M Figure p7.6 Problem 7.9: etermine the discharge at each pipe when the friction head loss in the pipe is 4 m in Fig. p7.7 and find the elevation of the reservoir E, draw the energy grade line of the system m 04.5 m E.Ç =000 m φ 600 λ =0.0 vana =400 m φ 800 λ =0.0? =00 m φ 000 λ =0.0 E Figure p

5 Problem 7.0: raw the energy grade lines of the systems below since the flow directions are known.. Solution: The energy grade lines have shown on the systems with dotted lines. Figure p7.8a Figure p7.8b Figure p7.8c 7-8

6 Figure p7.8d Figure p7.8e Figure p7.8f Figure p7.8g 7-8

7 Figure p7.8h Problem 7.: etermine the discharges in the parallel pipes and the pressure at if the pressure at point is 8 N/cm and at the pipe is open to the atmosphere in Fig. p7.9. For all pipes the Manning s roughness coefficient will be n=0.06. φ 400 =400 m φ 00 =000 m φ 00 φ 00 =800 m =000 m Figure p7.9 Problem 7.: In the system shown in Fig.7.0 water is pumped from to reservoir, find the power of the pump and draw the energy grade line of the system. The pipe length, discharge pumped from the pump, diameters of the pipes, and Kutter numbers were given in the figure 0 m =048 m =54 mm m = m =4878 m =406 mm m =0. Q =0.4 m /s =5 m =0 mm m =0. Figure p7.0a Problem 7.: The discharge of the pipe is 00 lt/s and the pipe is open to atmosphere at in the system shown in Fig. p7.. If the outlet of the pipe is at 00m; Find the elevation of the reservoir and the discharges of pipes () and (). raw the energy grade line of the system. 7-84

8 ? E.Ç. 90m =0.5 m =000 m k =0.05 cm =0.5 m =500 m k =0.0 cm =0. m =600 m k =0 00m Q =00 lt/s Figure p7. Problem 7.4: Solve the system by using Hardy-ross method in Fig.p7. (λ=0.0). 60 lt/s Ø00 =0 m Q0=45 lt/s r= Ø50 ; =6m Q0=5 lt/s ; r=5 0 lt/s Ø50 =0 m Q0=5 lt/s r= 40 lt/s Figure p