In the field of air pollution control, one often needs to sample the quality of a moving airstream. In such measurements a sampling probe is aligned with the flow as sketched in Fig. 9-51. A suction pump draws air through the probe at volume flow rate V as sketched. For accurate sampling, the air speed through the probe should be the same as that of the airstream (isokinetic samp ling). However if the applied suction is too large, as sketched in Fig. 9-51, the air speed through the probe is greater than that of the airstream (superisokinetic sampling). For simplicity consider a two-dimensional case in which the sampling probe height is h = 4.58 mm and its width (into the page of Fig. 9-51)is W= 39.5 mm. The values of the stream function corresponding to the lower and upper dividing streamlines are
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Fluid Mechanics: Fundamentals and Applications
- If the hematocrit of John's blood wereto change from 42% to 55% and at the same time the diameter of one ofJohn's vessels were to decrease by 1%. Using Poisselle's equation, by how much(and in what direction) would John's blood pressure have to change inorder to maintain the same volume flow rate?arrow_forwardA pitot-static tube to be used in 2n airplane for on-flight measurement was calibrated on ground by using air of density 1.20 kg/m? . A measurement taken at an altitude of 3000 m where the ambient pressure and density were 70 kPa (abs) and 0.91 kg/m? respectively, indicated a velocity of 200 m/s by using the above ‘ground level calibration. Estimate the true speed of the airplane [Take k = 1.4 2nd R = 287 J(kg Karrow_forwardWhat is the relationship between the pressure and the volume of air in cartesian diver?arrow_forward
- A pipe of diameter 2.5 m is required to transport an oil of sp.gr. 0.86 & viscosity 3×10- 2 poise at 3750 li/s. Tests were conducted on a 20cm diameter pipe using water at 20oC Find the velocity and rate of flow in the model. Viscosity of water at 20 m= 0.01poise.arrow_forwardA dimensionless combination of variables that is important in the study of viscous flow through pipes is called the Reynolds number, Re, defined as ???/? where, as indicated in Fig. 11, ? is the fluid density, V the mean fluid velocity, D the pipe diameter, and the fluid viscosity. A Newtonian fluid having a viscosity of 0.38 ? . ?/?² and a specific gravity of 0.91 flows through a 25‐mmdiameter pipe with a velocity of 2.6 ?/?. Determine the value of the Reynolds number using (a) SI units, and (b) BG units.arrow_forwardIn this lab we will drop a steel ball (Psteel = 8000 kg/m³, rball = 2.18 x10³ m) through the air (Nair = 1.8 x105 Pa.s, Pair = 1.29 kg/m³), and through a viscous soap solution (Nsoap = 9.0 Pa.s [you will measure this number in the lab, but use this number for the prelab], Psoap = 1000 kg/m³). %3D 1 Pa = 1 N/m?. Calculate the terminal speed of the ball falling through the air, assuming that inertial drag is the dominant contributor. (For a sphere CD = and A is the area of the circle of radius r of the ball). Neglecting drag, estimate the time in seconds it takes for the steel ball to reach the terminal speed found in part 2 (i). Neglecting drag, estimate how far the ball would have travelled before reaching its terminal speed and comment on whether it is reasonable to neglect drag when studying the motion of this ball as it falls through the air from rest from the top of a 30 cm tall beaker or even from the ceiling of the room. Neglecting drag it would take 36 m to reach the terminal…arrow_forward
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- Saturated steam at 99.6 °C is heated to 350°C. Use the steam table provided to determine: a. The required heat input if 1 kg of steam undergoes the process in a variable-volume constant-pressure container. b. The work of expansion (in kJ) of the steam undergoing the process. C. The required heat input if a continuous stream flowing at 1 kg/s undergoes the process at constant pressure. d. Does your numeric answer to part c equal the sum of parts b and a? Explain why or why not. Given: 1 bar = 10 N/m4, Q= AH, Q = AU, AA = AÛ + PAV, table B.7 in kJ/kg and m/kg.arrow_forwardDimensional Analysis and Hydraulic Similitude (fluid mechanics) 1. Water at 60F at 12 ft/s in a 6-in. pipe. (a) For dynamic similarity, determine the velocity of medium fuel oil at 90F flowing in a 12-in. pipe. (b) Determine the diameter of the pipe that should be used if a medium lubricating oil at 70oF if flowing at a velocity of 50 ft/s. find the: a. velocity : ____________________ fps b. diameter : ____________________ in.arrow_forward"lin' 2. In an undistur bed airstream, where the presure is 14.7 and the semperature is 519 °R the vélocity #kec what are the velocity , density j 600 the presure is 13.9 10/in2? temperature, and speed of sound wherearrow_forward
- Principles of Heat Transfer (Activate Learning wi...Mechanical EngineeringISBN:9781305387102Author:Kreith, Frank; Manglik, Raj M.Publisher:Cengage Learning