Info Ihl
3.14 Water flows from the faucet on the first floor of the building shown in Fig. P3.14 with a maximum velocity of 20 ft s. For steady inviscid flow, determine the maximum water velocity from the basement faucet and from the faucet on the second floor assume each floor is 12 ft tall . 3.11 Air flows smoothly past your face as you ride your bike, but bugs and particles of dust pelt your face and get into your eyes. Explain why this is so. 3.12 Water in a container and air in a tornado flow in...
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3.81 Water flows through the branching pipe shown in Fig. P3.81. If viscous effects are negligible, determine the pressure at section 2 and the pressure at section 3 . 3.84 Water flows through the horizontal Y-fitting shown in Fig. P3.84. If the flowrate and pressure in pipe 1 are Q1 2.3 ft3 s and P1 50 lb in.2, determine the pressures, P2 and P3, in pipes 2 and 3 under the assumption that the flowrate divides evenly between pipes 2 and 3 . 3.85 Water flows from the pipe shown in Fig. P3.85 as...
T 1
3.68 JP-4 fuel SG 0.77 flows through the Venturi meter shown in Fig. P3.68 with a velocity of 15 ft s in the 6-in. pipe. If viscous effects are negligible, determine the elevation, h, of the fuel in the open tube connected to the throat of the Venturi meter.
Xample 313
Water flows over a triangular weir, as is shown in Fig. E3.13. Based on a simple analysis using the Bernoulli equation, determine the dependence of the flowrate on the depth H. If the flowrate is Q0 when H H0, estimate the flowrate when the depth is increased to H 3H0. With the assumption that the flow is steady, inviscid, and incompressible, it is reasonable to assume from Eq. 3.18 that the average speed of the fluid over the triangular notch in the weir plate is proportional to V2gH. Also,...
Info Bav
3.20 Pop with the same properties as water flows from a 4-in. diameter pop container that contains three holes as shown in Fig. P3.20 see Video 3.5 . The diameter of each fluid stream is 0.15 in., and the distance between holes is 2 in. If viscous effects are negligible and quasi-steady conditions are assumed, determine the time at which the pop stops draining from the top hole. Assume the pop surface is 2 in. above the top hole when t 0. Compare your results with the time you measure from the...
Xample 314
Water is siphoned from the tank shown in Fig. E3.14 through a hose of constant diameter. A small hole is found in the hose at location 1 as indicated. When the siphon is used, will water leak out of the hose, or will air leak into the hose, thereby possibly causing the siphon to malfunction Whether air will leak into or water will leak out of the hose depends on whether the pressure within the hose at 1 is less than or greater than atmospheric. Which happens can be easily determined by using...
Water Flows Through The Horizontal Branching Pipe Shown
3.82 Water flows through the horizontal branching pipe shown in Fig. P3.82 at a rate of 10 ft3 s. If viscous effects are negligible, determine the water speed at section 2 , the pressure at section 3 , and the flowrate at section 4 . 3.80 The surface area, A, of the pond shown in Fig. P3.80 varies with the water depth, h, as shown in the table. At time t 0 a valve is opened and the pond is allowed to drain through a pipe of diameter D. If viscous effects are negligible and qua-sisteady...
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3.4 What pressure gradient along the streamline, dp ds, is required to accelerate water in a horizontal pipe at a rate of 30 m s2 3.5 At a given location the air speed is 20 m s and the pressure gradient along the streamline is 100 N m3. Estimate the air speed at a point 0.5 m farther along the streamline. 3.6 What pressure gradient along the streamline, dp ds, is required to accelerate water upward in a vertical pipe at a rate of 30 ft s2 What is the answer if the flow is downward
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3.54 The center pivot irrigation system shown in Fig. P3.54 is to provide uniform watering of the entire circular field. Water flows through the common supply pipe and out through 10 evenly spaced nozzles. Water from each nozzle is to cover a strip 30 feet wide as indicated. If viscous effects are negligible, determine the diameter of each nozzle, di, i 1 to 10, in terms of the diameter, dln, of the nozzle at the outer end of the 3.52 An inviscid, incompressible liquid flows steadily from the...
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3.71 Water, considered an inviscid, incompressible fluid, flows steadily as shown in Fig. P3.71. Determine h. 3.76 An ancient device for measuring time is shown in Fig. P3.76. The axisymmetric vessel is shaped so that the water level falls at a constant rate. Determine the shape of the vessel, R R z , if the water level is to decrease at a rate of 0.10 m hr and the drain hole is 5.0 mm in diameter. The device is to operate for 12 hr without needing refilling. Make a scale drawing of the shape...
V Lac
3.91 A weir see Video V10.7 of trapezoidal cross section is used to measure the flowrate in a channel as shown in Fig. P3.91. If the flowrate is Q0 when H 2, what flowrate is expected when H 3.92 Water flows down the sloping ramp shown in Fig. P3.92 with negligible viscous effects. The flow is uniform at sections 1 and 2 . For the conditions given, show that three solutions for the downstream depth, h2, are obtained by use of the Bernoulli and continuity equations. However, show that only two...
P314
3.13 As shown in Fig. P3.13 and Video V3.2, the swirling motion of a liquid can cause a depression in the free surface. Assume that an inviscid liquid in a tank with an R 1.0 ft radius is rotated sufficiently to produce a free surface that is h 2.0 ft below the liquid at the edge of the tank at a position r 0.5 ft from the center of the tank. Also assume that the liquid velocity is given by V K r, where K is a constant. a Show that h K2 1 r2 - 1 R2 2 . b Determine the value of K for this...
An Air Cushion Vehicle Is Supported By Forcing Air Into The Chamber Created By
grill is required to maintain the correct cooking conditions, determine the pressure within the grill near the holes. 3.88 An air cushion vehicle is supported by forcing air into the chamber created by a skirt around the periphery of the vehicle as shown in Fig. P3.88. The air escapes through the 3-in. clearance between the lower end of the skirt and the ground or water . Assume the vehicle weighs 10,000 lb and is essentially rectangular in shape, 30 by 50 ft. The volume of the chamber is large...
V Otl
3.57 The vent on the tank shown in Fig. P3.57 is closed and the tank pressurized to increase the flowrate. What pressure, p1, is needed to produce twice the flowrate of that when the vent is open 3.58 Water flows steadily through the large tanks shown in Fig. P3.58. Determine the water depth, hA. 3.59 Air at 80 F and 14.7 psia flows into the tank shown in Fig. P3.59. Determine the flowrate in ft3 s, lb s, and slugs s. Assume incompressible flow. 3.60 Water flows from a large tank as shown in...
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Consider a compressible fluid for which the pressure Repeat Problem 3.1 if the pipe is vertical with the flow 3.3 An incompressible fluid with density p flows steadily past the object shown in Video V3.3 and Fig. P3.3. The fluid velocity along the horizontal dividing streamline lt x lt a is found to be V V0 1 a x , where a is the radius of curvature of the front of the object and V0 is the upstream velocity. a Determine the pressure gradient along this streamline. b If the upstream pressure is...
T Xbn
3.89 A small card is placed on top of a spool as shown in Fig. P3.89. It is not possible to blow the card off the spool by blowing air through the hole in the center of the spool. The harder one blows, the harder the card sticks to the spool. In fact, by blowing hard enough it is possible to keep the card against the spool with the spool turned upside down. Note It may be necessary to use a thumb tack to prevent the card from sliding from the spool. Explain this phenomenon. 3.87 A conical plug...
B Figure P336
3.33 The speed of an airplane through the air is obtained by use of a Pitot-static tube that measures the difference between the stagnation and static pressures. See Video V3.4. Rather than indicating this pressure difference psi or rectly, the indicator is calibrated in speed mph or knots . This calibration is done using the density of standard sea level air. Thus, the air speed displayed termed the indicated air speed is the actual air speed only at standard sea level conditions. If the...
B Figure P339
3.40 An inviscid fluid flows steadily along the stagnation streamline shown in Fig. P3.40 and Video V3.3, starting with speed V0 far upstream of the object. Upon leaving the stagnation point, point 1 , the fluid speed along the surface of the object is assumed to be given by V 2 V0 sin U, where U is the angle indicated. At what angular position, U2, should a hole be drilled to give a pressure difference of p1 p2 pV2 2 Gravity is negligible. 3.41 A cetain vacuum cleaner can create a vacuum of 2...
Info Vbx
very thin shear layer between 4 and 5 in which adjacent fluid particles interact and rotate or spin. This produces a rotational flow. A more complete analysis would show that the Bernoulli equation cannot be applied across streamlines if the flow is rotational see Chapter 6 . V_ The Bernoulli equation is not valid for flows that involve pumps or turbines. As is suggested by Example 3.18, if the flow is irrotational that is, the fluid particles do not spin as they move , it is appropriate to use...
3
In the previous two sections, we developed the basic equations governing fluid motion under a fairly stringent set of restrictions. In spite of the numerous assumptions imposed on these flows, a variety of flows can be readily analyzed with them. A physical interpretation The Bernoulli equation can be written in terms of heights called heads. of the equations will be of help in understanding the processes involved. To this end, we rewrite Eqs. 3.7 and 3.12 here and interpret them physically....
B Figure P334
3.38 The circular stream of water from a faucet is observed to taper from a diameter of 20 mm to 10 mm in a distance of 50 cm. Determine the flowrate. 3.39 Water is siphoned from the tank shown in Fig. P3.39. The water barometer indicates a reading of 30.2 ft. Determine the maximum value of h allowed without cavitation occurring. Note that the pressure of the vapor in the closed end of the barometer equals the vapor pressure. 3.35 A 0.15-m-diameter pipe discharges into a 0.10-m-di-ameter pipe....
Info Pdh
3.53 Air assumed frictionless and incompressible flows steadily through the device shown in Fig. P3.53. The exit velocity is 100 ft s, and the differential pressure across the nozzle is 6 lb ft2. a Determine the reading, H, for the water-filled manometer attached to the Pitot tube. b Determine the diameter, d, of the nozzle. 3.50 Water is pumped from a lake through an 8-in. pipe at a rate of 10 ft3 s. If viscous effects are negligible, what is the pressure in the suction pipe the pipe between...