A cricket ball travels at 130 km/h through air at 20 degrees Celsius. The cricket ball has a diameter of 220 mm such that the Reynolds number is Re = 529,630. Which of the following answers is closest to the ratio of the largest to smallest (Kolmogorov) length scales in this flow. The Kolmogorov scale is dependent on the Reynolds number and the largest turbulent scale can be estimated as 1/5 of the characteristic geometrical scale of the flow. 19632 %3D NK 190, 632 NK 19 NK 0.19 NK

A cricket ball travels at 130 km/h through air at 20 degrees Celsius. The cricket ball has a diameter of 220 mm such that the Reynolds number is Re = 529,630. Which of the following answers is closest to the ratio of the largest to smallest (Kolmogorov) length scales in this flow. The Kolmogorov scale is dependent on the Reynolds number and the largest turbulent scale can be estimated as 1/5 of the characteristic geometrical scale of the flow. 19632 %3D NK 190, 632 NK 19 NK 0.19 NK

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

See similar textbooks

Similar questions

Water is flowing in a pipe with radius of 25.4 cm at velocity of 5 m/s. The viscosity of water is 1.131 Pa-s and its density is equal to 997.9 ??/?^3.What is its Reynolds number and type of fluid flow?
P1 A thin layer of water flows down a plate inclined to the horizontal with an angle a = 15° in the shown coordinate system. If the thickness of the water layer is a=0.5 mm, assuming that the flow is laminar and incompressible, (water density p = 1000 kg/m³viscosity µ = 0.001 Pa.s and acceleration of gravity g = 9.81 m/s²) and an air flow shears the layer in a direction opposite to its flow with a shear stress of 1 N /m². Solve the Navier-Stokes equation: air water (a) to find the value of the maximum water velocity in m/s to three decimal points, Answer: (b)and to find the value of water velocity at the layer's surface in m/s to three decimal points, Answer:
Pipelines are cleaned by pushing through them a closefitting cylinder called a pig . The name comes from thesquealing noise it makes sliding along. Reference 50describes a new nontoxic pig, driven by compressed air, forcleaning cosmetic and beverage pipes. Suppose the pigdiameter is 5-15/16 in and its length 26 in. It cleans a6-in-diameter pipe at a speed of 1.2 m/s. If the clearance isfi lled with glycerin at 20 8 C, what pressure difference, inpascals, is needed to drive the pig? Assume a linear velocityprofi le in the oil and neglect air drag.
1- Reynolds number is a dimensionless number represent .....to .. 2- The velocity profile of the flow between two parallel plates is linear if the pressure gradient equal and parabolic if the pressure gradient has a .... 3- In the sink and source flow the potential function is represented as.. ...... and the stream function is represented as **** 4- In the laminar boundary layer, the .............. is the dominant reason for the loss while in turbulent boundary layer the is dominant. 5- For inviscid flow, there are no shear stresses the only forces acting on a fluid element are ....... and. *****
Consider a two-dimensional (planar), steady and incompressible flow in the en- trance region of a duct leading to the fully developed region, as shown. Velocity profile at the entrance is U, which is uniform. At length L the flow becomes fully developed. Fluid viscosity is μ and its density of p. Pressure is uniform in the vertical (y) direction. Consider unity width normal to the page. Vo h L เง I x u Find the fully-developed velocity profile u(y) at x ≥ L. Using continuity equa- tion, express the velocity profile in terms of Uo, y and h only. Find the pressure gradient dp/dr and wall shear stress in the fully developed region (x > L) in terms of μ, U₁ and h. Calculate the total friction force acting on the walls in the entrance region (0 < x
1. The Stokes-Oseen formula for drag force Fon a sphere of diameter D in a fluid stream of low velocity V, density p, and viscosity u is: 9T F = 3TuDV + 16PD? Is this formula dimensionally homogenous? 2. The efficiency n of a pump is defined as the (dimensionless) ratio of the power required to drive a pump: QAp input power Where Q is the volume rate of flow and Ap is the pressure rise produced by the pump. Suppose that a certain pump develops a pressure of Ibf/in? (1ft = 12 in) when its flow rate is 40 L/s (1L =0.001 m). If the input power is 16hp (1hp = 760 W), what is the efficiency?
The radius of the blood vessel is 0.9 cm with a viscosity and density of 0.004 kg/(m-sec) and 1010 kg/m^3. Find the Reynolds number if the flow velocity is 0.18 m/sec? 1018 918 618 718 818 Kinematic similarity is about similarity of ...
Mott ." cometer, which we can analyze later in Chap. 7. A small ball of diameter D and density p, falls through a tube of test liquid (p. µ). The fall velocity V is calculated by the time to fall a measured distance. The formula for calculating the viscosity of the fluid is discusses a simple falling-ball vis- (Po – p)gD² 18 V This result is limited by the requirement that the Reynolds number (pVD/u) be less than 1.0. Suppose a steel ball (SG = 7.87) of diameter 2.2 mm falls in SAE 25W oil (SG = 0.88) at 20°C. The measured fall velocity is 8.4 cm/s. (a) What is the viscosity of the oil, in kg/m-s? (b) Is the Reynolds num- ber small enough for a valid estimate?
Please help me in answering the following practice question. Thank you for your help. Consider several elementary planar irrotational flows arranged in a plane in a cartesian coordinate system (x-y plane) with the unit of length in m (meter). A line source with strength 18 m^2/s is located at point A (0, 1); a line sink with strength of 15 m^2/s is located at point B (3, -2); a line vortex with strength of 9 m^2/s is located at point C (4, 1); and a uniform flow of 10 m/s is at angle 30° with positive x-direction (counter-clockwise). Find the resultant velocity and pressure induced at point D (2, 0) by the uniform stream, line source, line sink & line vortex. Pressure at the infinity at upstream of uniform flow is 1000 Pa.Please list all necessary assumptions.
Consider steady, incompressible, laminar, fully developed, planar Poiseuille flow between two parallel, horizontal plates (velocity and pressure profiles are shown in Fig. At some horizontal location x = x1, the pressure varies linearly with vertical distance z, as sketched. Choose an appropriate datum plane (z = 0), sketch the profile of modi fied pressure all along the vertical slice, and shade in the region representing the hydrostatic pressure component. Discuss.
Two parallel plates, one moving at 4 m/s and the otherfi xed, are separated by a 5-mm-thick layer of oil of specific gravity 0.80 and kinematic viscosity 1.25 E-4 m 2 /s.What is the average shear stress in the oil?( a ) 80 Pa, ( b ) 100 Pa, ( c ) 125 Pa, ( d ) 160 Pa, ( e ) 200 Pa
Laminar Flow in a Vertical Cylindrical Annulus Derive the equation for steady-state laminar flow inside the annulus between two concentric vertical pipes. This type of flow occurs often in concentric pipe heat exchangers. max velocity profile