4. Under certain conditions, wind blowing past a rectangular speed limit sign can cause the sign to oscillate with a frequency (see Fig.). Assume that is a function of the sign width, b; sign height, h; wind velocity, V; air density, p; and an elastic constant, k, for the supporting pole. The constant, k, has dimensions of Nm. (a) Develop a suitable set of pi terms for this problem using b, V, and p as repeating variables. (b) List all the other possible combinations of repeating variables that could have been utilized for this problem.

4. Under certain conditions, wind blowing past a rectangular speed limit sign can cause the sign to oscillate with a frequency (see Fig.). Assume that is a function of the sign width, b; sign height, h; wind velocity, V; air density, p; and an elastic constant, k, for the supporting pole. The constant, k, has dimensions of Nm. (a) Develop a suitable set of pi terms for this problem using b, V, and p as repeating variables. (b) List all the other possible combinations of repeating variables that could have been utilized for this problem.

Name: 4. Under certain conditions, wind blowing past a rectangular speed li
Uploaded: 2024-03-20T06:56:55.000Z
Channel: Bartleby
Description: 4. Under certain conditions, wind blowing past a rectangular speed limit sign can cause the signto oscillate with a frequency (see Fig.). Assume that is a function of the sign width, b; signheight, h; wind velocity, V; air density, p; and an elastic

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 5.8P

See similar textbooks

Similar questions

The pressure drop per unit length in horizontal pipe flow,∆ p/L , depends on the fluid density ρ , viscosity μ , diameterD , and volume flow rate Q . Rewrite this function in termsof pi groups.
Example: A fan of diameter 0.7 m running 1500 rpm delivers 140 m3/min of air at 15C against 75 mm of water total pressure when the total effeciency is 86%. Determine the volume of air delivered, total pressure and power consumed, if (a) the air temperature is 50C. (b) the air temperature is 50C and the fan speed is 1700 rpm. (c) the same conditions as (b) but a 0.6 m diameter, geometrically similar fan is used.
Chapter 7, Problem 63, there is an 'h' value that is solved when expressing half the width of the Rankine Oval that I am not quite understanding the process by which the value is solved for. Could you break down the process by which h=0.02423 m? It's been a while since I was last in school, so the mathematical method by which 'h' was solved is a little unclear to me.
If the given Pi is 3.14159 Capillary tube: radius = 0.02 cm; length = 9 cm; pressure = 0.7 mmHg Liquid sample: density = 4 ml; time of flow = 4.5 seconds What is the pressure in MKS unit and CGS unit? What is its viscosity? If the weight is 8.5 g, what is its density? What is its kinematic viscosity? What is its fluidity?
A ship is towing a sonar array that approximates a submergedcylinder 1 ft in diameter and 30 ft long with itsaxis normal to the direction of tow. If the tow speed is12 kn (1 kn = 1.69 ft/s), estimate the horsepower requiredto tow this cylinder. What will be the frequency of vorticesshed from the cylinder? Use Figs.
The power P required to drive a propeller is known to depend on the diameter of the propeller D, the density of fluid ρ, the speed of sound a, the angular velocity of the propeller ω, the freestream velocity V , and the viscosity of the fluid µ. (a) How many dimensionless groups characterize this problem? (b) If the effects of viscosity are neglected, and if the speed of sound is not an important variable, express the relationship between power and the other variables in nondimensional form. (c) A one-half scale model of a propeller is built, and it uses Pm horsepower when running at a speed ωm. If the full-scale propeller in the same fluid runs at ωm/2, what is its power consumption in terms of Pm if the functional dependence found in part (b) holds? What freestream velocity should be used for the model test?
Given problem: a.) At temperatures of 100° F and 120 psi absolute, calculation of above properties for methane (CH4): what is the barometric pressure if the gauge reading is 104.5 Psig? b.) A pipe transports an incompressible fluid. The volume flow rate is 10m3/s at point 1 along the pipe. The area halves at spot 2 along the pipe. At site 2, what is the volume flow rate?
Find the following based on the graphs given (angle of attack: 6 degrees, Re: 3.01*10^6, chord length: 0.75m, velocity: 60 m/s, standard atmosphere):
A 30 mm diameter shaft rotates in a 30.1 mm inner diameter and 60 mm long bearing with a frequency of 5000 rpm. At that frequency it can be assumed that the eccentricity is zero. The lubricant used is SAE-30 oil at 60 ° C (μ = 4 x 10-2 Nm-2s). What is the power absorbed by the mechanism? Remember that W = C. ω, Where: ω = angular velocity = 2πf, C = conjugate (moment or torque) and 1hp = 736W = 75 kg.m/s. Expected Answer: w = 0.38hp
The power P generated by a certain windmill design depends upon its diameter D, the air density ρ, the wind velocity V, the rotation rate Ω, and the number of blades n. A model windmill, of diameter 50 cm, develops 2.7 kW at sea level when V = 40 m/s and when rotating at 4800 rev/min. What power will be developed by a geometrically and dynamically similar prototype, of diameter 5 m, in winds of 10 m/s at 2000 m standard altitude? At 2000 m altitude, ρ = 1.0067 kg/m3. At sea level, ρ = 1.2255 kg/m3. A model windmill, of diameter 50 cm, develops 2.7 kW at sea level when V = 40 m/s and when rotating at 4800 rev/min. What is the appropriate rotation rate of a geometrically and dynamically similar prototype, of diameter 5 m, in winds of 10 m/s at 2000 m standard altitude?
A prototype ocean platform piling is expected to encountercurrents of 150 cm/s and waves of 12-s period and 3-mheight. If a one-fifteenth-scale model is tested in a wavethe channel, what current speed, wave period, and wave heightshould be encountered by the model?
1. An automobile radio aerial consists of three sections having diameters in., in., and in. Find the frequency of the vortex shedding when the car is traveling at 35 mph and 65 mph. 2. For problems 9.36 and 9.37 find the vortex shedding frequency. Estimate the wavelength between successive vortices. problem 9.36: Air flows over a 60 f t high circular smoke stack at a uniform speed of 30 mph. Find the total force acting on the stack if its diameter is 6 f t and the air temperature is 70°F. problem 9.37: A 0.5 in. diameter cable is strung between poles 120 f t apart. A 60 mph wind is blowing at right angles to the cable. Find the force acting on the cable due to the wind. The air temperature is 40°F.