Question 11) Vortices are usually shed from the rear of a cylinder, which are placed in a uniform flow at low speeds. The vortices alternatively leave the top and the bottom of the cylinder, as shown in figure, causing an altemating force normal because of generating a dimensionless relationship for Kánmán vortex shedding frequency f (1/s) as a function of free-stream speed V(7m/s), fluid density p (kgm³), fluid viscosity µ (kg/m.s), sound velocity c (m/s), surface roughness & (m) and cylinder diameter D(m). || I-Determine the nondimensional a parameters using repeating variables, involving f, , c and u as nonrepeating variables ii-the dynamics of Bhosphorus bridge is investigated in a wind tunnel for the vortex generation behind the wires. A 1/59 scaled down model of the hanging wires is used in the laboratory. If vortex shedding frequency of of Bhosphorus bridge 590 Hz is measured in the laboratory at 29 m/s. Then detemine the expected frequency in the actual case exposed to 190 km/h wind velocity.

Question 11) Vortices are usually shed from the rear of a cylinder, which are placed in a uniform flow at low speeds. The vortices alternatively leave the top and the bottom of the cylinder, as shown in figure, causing an altemating force normal because of generating a dimensionless relationship for Kánmán vortex shedding frequency f (1/s) as a function of free-stream speed V(7m/s), fluid density p (kgm³), fluid viscosity µ (kg/m.s), sound velocity c (m/s), surface roughness & (m) and cylinder diameter D(m). || I-Determine the nondimensional a parameters using repeating variables, involving f, , c and u as nonrepeating variables ii-the dynamics of Bhosphorus bridge is investigated in a wind tunnel for the vortex generation behind the wires. A 1/59 scaled down model of the hanging wires is used in the laboratory. If vortex shedding frequency of of Bhosphorus bridge 590 Hz is measured in the laboratory at 29 m/s. Then detemine the expected frequency in the actual case exposed to 190 km/h wind velocity.

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Description: Question 11) Vortices are usually shed from the rear of a cylinder, which are placed in a uniform flow at lowspeeds. The vortices alternatively leave the top and the bottom of the cylinder, as shown in figure, causing analtemating force normal becau

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

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Vortices are usually shed from the rear of a cylinder, which are placed in a uniform flow at low speeds. The vortices alternatively leave the top and the bottom of the cylinder, as shown in figure, causing an alternating force normal because of generating a dimensionless relationship for Kármán vortex shedding frequency fk (1/s) as a function of free-stream speed V(m/s), fluid density r (kg/m3), fluid viscosity µ (kg/m.s), sound velocity c (m/s), surface roughness ɛ (m) and cylinder diameter D(m). Solve the problem by making the necessary assumptions and drawing the schematic figure. I-Determine the nondimensional p parameters using repeating variables, involving f, ɛ, c and µ as nonrepeating variables ii-the dynamics of Bhosphorus bridge is investigated in a wind tunnel for the vortex generation behind the wires. A 1/56,2 scaled down model of the hanging wires is used in the laboratory. If vortex shedding frequency of of Bhosphorus bridge 562 Hz is measured in the laboratory at…
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.
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Assume an inviscid, incompressible flow. Also, standard sea level density and pressure are 1.23 kg/m3 (0.002377 slug/ft3) and 1.01 × 105 N/m2 (2116 lb/ft2), respectively. Consider the lifting flow over a circular cylinder of a given radius and witha given circulation. If V∞ is doubled, keeping the circulation the same,does the shape of the streamlines change? Explain.
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Some engineers want a good estimate of drag and boundary-layerthickness at the trailing edge of a miniature wing. The chord and span ofthe wing are 6 mm and 30 mm, respectively and a typical flight speed is5 m/s in air (kinematic viscosity = 15 × 10−6 m2/s; density = 1.2kg/m3). An engineer may decide to make a superseding model withchord and span of 150 mm and 750 mm, respectively. Measurements onthe model in a water channel flowing at 0.5 m/s (kinematic viscosity = 1× 10−6 m2/s, density = 1000 kg/m3) give a drag of 0.19 N and aboundary-layer thickness of 3 mm. Estimate the corresponding values forthe prototype