A small low-speed wind tunnel is designed to calibrate hot wires (anemometer wires) (Figure 2). The air temperature is 19 °C. The test section of the wind tunnel is 30 cm in diameter and 30 cm in height. The flow through the test section must be as uniform as possible. The speed range of the wind tunnel varies from 1 m/s to 8 m/s, and the design will be optimized with an airspeed of V= 4.0 m/s in the test section. For a flow state at a speed of 4.0 m/s, which is almost uniform at the entrance to the test section, how fast does the air velocity on the tunnel axis accelerate to the end of the test section? Note: kinematic viscosity of air at 19 °C v=1.507x10$ m²/s flow rectifiers spreader test silencer fan section Figure 2. schematic view of the wind tunnel

A small low-speed wind tunnel is designed to calibrate hot wires (anemometer wires) (Figure 2). The air temperature is 19 °C. The test section of the wind tunnel is 30 cm in diameter and 30 cm in height. The flow through the test section must be as uniform as possible. The speed range of the wind tunnel varies from 1 m/s to 8 m/s, and the design will be optimized with an airspeed of V= 4.0 m/s in the test section. For a flow state at a speed of 4.0 m/s, which is almost uniform at the entrance to the test section, how fast does the air velocity on the tunnel axis accelerate to the end of the test section? Note: kinematic viscosity of air at 19 °C v=1.507x10$ m²/s flow rectifiers spreader test silencer fan section Figure 2. schematic view of the wind tunnel

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter5: Analysis Of Convection Heat Transfer

Section: Chapter Questions

Problem 5.9P: When a sphere falls freely through a homogeneous fluid, it reaches a terminal velocity at which the...

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