Example 12.4 Given: A 1/20 scale model of a high-rise building is tested in a wind tunnel. The drag force of the model on the rectangular face is measured to be 200 N for a wind speed of 20 m/s. Find: The drag force on the prototype building in a 40 m/s wind velocity using the drag coefficient conservation. Note: prototype height=3w. Tair = constant Match force coefficients. CFP F₂ Fm F₂ F₂ = = = 1x = = = CFm Pp Pm = (2)'()* Lm. 40 m/s 20 m/s 1600 1600 × Fm 1600 × 200 N 320 kN 20² K W. Prototype Vm Model

Example 12.4 Given: A 1/20 scale model of a high-rise building is tested in a wind tunnel. The drag force of the model on the rectangular face is measured to be 200 N for a wind speed of 20 m/s. Find: The drag force on the prototype building in a 40 m/s wind velocity using the drag coefficient conservation. Note: prototype height=3w. Tair = constant Match force coefficients. CFP F₂ Fm F₂ F₂ = = = 1x = = = CFm Pp Pm = (2)'()* Lm. 40 m/s 20 m/s 1600 1600 × Fm 1600 × 200 N 320 kN 20² K W. Prototype Vm Model

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

A two-story hospital is shown in the figure and must withstand an estimated wind speed of 145km/h and is located in an urban area surrounded by buildings. Determine the design wind pressure on all four sides of the hospital. Assume that the main entrance is the windward region. The building has a period of vibration of 0.4s. The dimensions of the structure are in feet, transform to meters. Subject : Structural Analysis 15' 15' 日日日日日 11 日日 100' 100
WILEY 8.75 PLUS 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?
Experiments were conducted in a wind tunnel with a wind speed of 50 km/hr on a flat plate of size 2m long and 1 m wide. The density of air is 1.15 kg/m³. The co-efficient of lift and drag are 0.75 and 0.15 respectively. Determine the lift force, drag force and resultant force.
Numerical Integration Example 3: A wind force distributed against the side of a building 240m high is Measured as: Height, h, (m) 0 30 60 90 120 150 180 210 240 Force, fh), (N/m)0 340 1200 1600 2700 3100 3200 3500 3800 Compute the total force and its location (line of action) due to this distributed wind force. (Use Simpson's rule) 3 240 m
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 200-lb block is on top of a 300-lb block and both blocks are tied to a pulleya pulley that is attached to the wall, as shown in the figure. The coefficient of static friction between thetwo blocks is 0.3 and between the 300 lb block and the floor is 0.4. The coefficient of dynamic frictionbetween all surfaces is 0.25. Disregard the friction at the pulley.Determine the minimum force that must be applied to the 300 lb block in order for it to initiatemotion (imminent motion).
Consider a uniform 10mlong beam, with flexural rigidity of 15,000Nm2that is clamped on the left hand side and with a roller support on the right hand side.1.What are the boundary conditions for this beam?2.Calculate Green’s function for this beam.
b) A wing of an aircraft of 13 m span and 2.5 m mean chord is designed to develop a lift of 50 kN at a speed of 350 km/h. A 1/19 scale model of the wing section is tested in a wind tunnel at 450 m/s and p= 5.33 kg/m³. The total drag measured is 390 N. Assuming that the wind tunnel data refer to a section of infinite span, calculate the total drag for the full-size wing. Assume an elliptical lift distribution and take air density as 1.2 kg/m³. Take the coefficient of induced drag as, Tt x Aspect ratio
2. Four machines are equally spaced along the length of an 8 m fixed- free beam of elastic modulus 210 x10° N/m² and cross-section moment of inertia 1.6x10 mt, as shown in Figure 2. Determine the flexibility matrix for a four degree-of-freedom model of the system with the location of the machines as the generalized coordinates. 2 m - 2m 2 m- E-210x 10° Nim 1-1.6x 10 kg-m Figure 2. Four machines along the span of a fixed-free beam.
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).
A 1-meter-long, simply supported copper beam (E = 117 GPa) carries uniformly distributed load q. The maximum deflection is measured as 2.5 mm. (Use available deflection formulas. All beams have constant flexural rigidity EI.) (a) Calculate the magnitude of the distributed load q (in kN/m) if the beam has a rectangular cross section (width b = 25 mm, height h = 50 mm). kN/m (b) If instead the beam has circular cross section and q = 500 N/m, calculate the radius r (in mm) of the cross section. Neglect the weight of the beam. mm
A beam has a natural frequency of 1.179 hz and a damping ratio of 5%. It’s subjected to loads that would cause 2.38 mm of displacement if the loads were applied statically. However the loads oscillate at a frequency of 0.844hz. Calculate the maximum displacement.