A Cessna 172 has a chord length of 5 ft and a cruise speed of 140 mph (or 205 ft s). The scaled model in a wind tunnel has a chord length of 2.5 ft. To achieve Reynolds number similarity, assuming the same air density and viscosity at model- and full-scale, the airspeed in wind tunnel testing should be set to: 102.5 fts 1 410 fts 1 820 fts 1 205 fts 1

A Cessna 172 has a chord length of 5 ft and a cruise speed of 140 mph (or 205 ft s). The scaled model in a wind tunnel has a chord length of 2.5 ft. To achieve Reynolds number similarity, assuming the same air density and viscosity at model- and full-scale, the airspeed in wind tunnel testing should be set to: 102.5 fts 1 410 fts 1 820 fts 1 205 fts 1

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

See similar textbooks

Similar questions

The drag force of a new sports car is to be predicted at a speed of 60 mi/h at an air temperature of 25 C. Automotive engineers build a 0.333333333333333 scale model of the car to test in a wind tunnel. The temperature of the wind tunnel air is also 25 C. Determine how fast (in mi/h) the engineers should run the wind tunnel to achieve similarity between the model and the prototype
(a) Explain on how the drag force on a prototype car can be predicted from the scale model? (c) In a wind tunnel experiment, a drag force on 1:8 scale model billboard is 1 kN. The airin the wind tunnel is 20 degree Celsius. During a storm, the wind speed can reach 20km/hr with air temperature of 10 degree Celsius. Determine the drag force experienceby the billboard during storm.
You are to conduct wind tunnel testing of a new football design that has a smaller lace height than previous designs. It is known that you will need to maintain a Re and St similarity for the testing. Based on standard college quarterbacks, the prototype parameters are set at V = 40 mph and ω = 300 rpm, where V and ω are the speed and angular velocity of the football. The prototype football has a 7 in. diameter. Due to instrumentation required to measure pressure and shear stress on the surface of the football, the model will require a length scale of 2:1 (the model will be larger than the prototype). Determine the required model freestream velocity and model angular velocity. [Answer in units of mph and rpm].
Why does the figure in Fh has 2.5 and 4? Even though its not in the given.
b. A 2.5m ship model was tested in fresh water (p = 1000kg/m³) and measurements indicated that there was a resistance of 45N when the model was moved at 2m/s. Work out the velocity of 40m phototype. Also find the force required to drive the prototype at this speed through sea water (p = 1025kg/m³).
Consider a classically configured airplane with the following parameters: weight W = 120 kN !! wing area S = 50 m2 area of horizontal tail S = 12 m2 airplane lift curve slope C1a = 0.08 / degree tail lift curve slope CLa = 0.06 / degree horizontal tail volume V = 0.9 In two subsequent flight tests in air of density p = 0.55 kg/m³, the airplane is trimmed for straight, level and unaccelerated flight at different velocities. The following velocites v and associated tail incidences i, are recorded: Test 1 Test 2 Vx (m/s) 120 220 ų (degrees) 2.5 2.0 Use this data to calculate the static margin SM. Enter your answer as a decimal number (NOT in %) in the text box and upload your workings together with those of Question 1 as described in the instructions above.
A model of a high-rise office building at 1/550 scale is tested in a wind tunnel to estimate the pressures and forces on the full-scale structure. The wind-tunnel air speed is 20 m/s at 20°C and atmospheric pressure, and the full-scale structure is expected to withstand winds of 200 km/h (10°C). If the extreme values of the pressure coefficient are found to be 1.0, –2.7, and –0.8 on the windward wall, side wall, and leeward wall of the model, respectively, what corresponding pressures could be expected to act on the prototype? If the lateral wind force (wind force on building normal to wind direction) was measured as 20 N in the model, what lateral force might be expected in the prototype in the 200 km/h wind?
A thin plate weighting 100 gm. takes 3 sec, to fall a distance of one meter in a liquid with a specific gravity of 0.92 between two vertical boundaries 0.5 cm apart, the plate moves at a mid-distance If the surface area of the plate is (1.5) m. What are the dynamic viscosity of the liquid and the kinematic viscosity?
A sign is being towed at a constant velocity of 4 m/s at an altitude of 100 m where air has a density of 1.20 kg/m³ and absolute viscosity of 1.5 x 10-5 Pa-s. Assume that the sign has the same resistance characteristics as a flat plate and neglect the effect of the plane on the free-stream velocity. a) the boundary layer is laminar or turbulent. b) What is the boundary layer thickness at the tail end of the sign? Indicate whether What is the boundary shear stress at the tail end of the sign? Estimate the power required to tow the sign. 2.0 m FLUID MECHANICS FOR ALL ENGINEERS 30 m
6. A 1: 25 scale model of a ship has a submerged surface area of 6 m², a length of 5 m and experiences a total drag of 25 N when towed through water with a velocity of 1.2m/s. Estimate the total drag on the prototype when cruising at the corresponding speed. The skin friction force can be estimated by F. = C Ap V2/2 where the coefficient C = 0.0735/(Re)1/5 S Assume water = 1 x 10-³ Pa.s and P water both model and the prototype. = 1030 kg/m³ for
A slab of concrete used in highway construction is set in place when the ambient temperature is 20 degrees celsius. If its length at that time is 20.478m, calculate the minimum gap required between concrete slabs if buckling is to be prevented. Assume the maximum temperature that will be reached is 55 degrees celsius.
An aircraft is flying in level flight at a speed of 200 km/h through air (density, p = 1.2 kg/m³, and viscosity, µ = 1.6 x 10-5 N-s/m²). The lift coefficient at this speed is 0.4 and the drag coefficient is 0.0065. The mass of the aircraft is 800 kg. The effective lift area of the aircraft is