An underwater device which is 2m long is to be moved at 4 m/sec. If a geometricallysimilar model 40 cm long is tested in a variable pressure wind tunnel at a speed of 60m/sec with the following information,Poir at Standard atmospheric pressure = 1.18kg/m³Pwater = 998kg/m3Hair = 1.80 x 10-5 Pa-s at local atmospheric pressure andHwater = 1 × 10-3 Pa-s then the pressure of the air in the model usedtimes local atmospheric pressureis

By pressure modelling - PprototypePmodel= ρV2prototypeρV2modelPatmPmodel=…

Answered: An underwater device which is 2m long…

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

See similar textbooks

Similar questions

A- Womersley number (a) of a human aorta is 20 and for the rabbit aorta is 17, the blood density is approximately the same across the species. The values of viscosity were 0.0035 Ns/m² for the human and 0.0040 Ns/m² for the rabbit. The diameter of the aorta is 2.0 cm for the man, and 0.7 cm for the rabbit, estimate the heart rate beats per minute (bpm) for both species
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?
A football, meant to be thrown at 60 mi/h in sea-level air( ρ = 1.22 kg/m 3 , μ = 1.78 E-5 N . m 2 ), is to be testedusing a one-quarter scale model in a water tunnel ( ρ =998 kg/m 3 , μ = 0.0010 N . s/m 2 ). For dynamic similarity,what is the ratio of prototype force to model force?( a ) 3.86 : 1, ( b ) 16 : 1, ( c ) 32 : 1, ( d ) 56 : 1, ( e ) 64 : 1
Global warming will produce rising sea levels partly due to melting ice caps and partly due to the expansion of water as average ocean temperatures rise. To get some idea of the size of this effect, calculate the change in length, Ah (in mm), of a column of water 1.5 km high for a temperature increase of 1.2 °C.Assume the column is not free to expand sideways. As a model of the ocean, that is a reasonable approximation, as only parts of the ocean very close to the surface can expand sideways onto land, and only to a limited degree. As another approximation, neglect the fact that ocean warming is not uniform with depth. Properties of water: 3 = 210 x 10 /C. c= 4186 J/kg - °C, L; = 334 kJ/kg, Le = 2256 kJ/kg Enter you answer below (to the nearest mm): Ah (in mm) = Type your answer.
2. The apparatus shown below is designed to measure the density of an unknown fluid (p2₂). The two sides of the device are separated by a movable, frictionless partition. The partition is attached to the immobile sidewalls of the device via springs (different spring constants) on either side. Before pouring fluid into the device, both springs are unstretched. The device has a rectangular cross-section and extends a width w into the page. Derive an expression for the unknown density p2 = f(p1, h₁, h₂, k₁, k2, Ax, g), where Ar is the displacement of the partition relative to its equilibrium location before the fluids are poured into the apparatus. h₁ P1 k₁ 5 P2 ли Ax k₂ h₂
Wind tunnel test section km/h Model FD Moving belt Drag balance The aerodynamic drag of a new Volvo FH truck is to be predicted at a speed of 85 km/h at an air temperature of 25°C (p=1.184 kg/m³, u=1.849x10-5kg/m-s). Volvo engineers build a 1/2 scale model of the FH to test in a wind tunnel. The temperature of the wind tunnel is also 25°C. The drag force is measured with a drag balance, and the moving belt is used to simulate the moving ground. Determine how fast the engineers should run the wind tunnel to achieve similarity between the model and the prototype.
1. (a) The motion of a floating vessel through the surrounding fluid results in a drag force D which is thought to depend upon the vessel's speed v, its length I, the density p and dynamic viscosity μ of the fluid and the acceleration due to gravity g. Show that:- D = pv²1² (1) (b) In order to predict the drag on a full scale 50m long ship traveling at 7m/s in sea water at 5°C of density 1027.7225 kg/m³ and viscosity 1.62 x 103 Pa.s, a model 3m long is tested in a liquid of density 805 kg/m³. What speed does the model need to be tested at and what is the required viscosity of the liquid?
2 A prototype car is designed for cold weather operation in Denver (-10°C, 83 kPa, altitude 1600m, µ = 1.741 × 10-5 Pas). It's drag force is to be tested in a 1:7 model in a wind tunnel at 150 mph under standard sea level conditions. If the model and prototype satisfy dynamic similarity what prototype velocity, in mph, is matched? Is this a reasonable test? 1 mile = 1609 m HINT: p = pRT
1. A model submarine is tested in a sea water tank at a speed of 30 m/s. The prototype speed should be 21.6 km/hr. (a) Determine the geometric scale between the model and the prototype (b) Determine the model speed if it is tested in a pressurized air wind tunnel with 12/s. kinematic viscosity v = 8 × 10-7 m² /s. For sea water use v = 1.124 × 10-6 m² /s.
Problem 4: The power P developed by a wind turbine is a function of diameter D, air density p, wind speed V, and rotational rate @. Viscous effect is negligible. (4a) Rewrite the above relationship in a dimensionless form; (4b) In a wind tunnel, a small model with a diameter of 90cm, rotating at 1200 RPM (revolution per minute), delivered 200 watts when the wind speed is 12m/s. The data are to be used for a prototype of diameter of 50m and wind speed of 8 m/s. For dynamic similarity, what will be (i) the rotational speed of the prototype turbine? (ii) the power delivered by the prototype turbine? Assume air has sea-level density.
2. A student team is to design a human-powered submarine for a design competition. The overall length of the prototype submarine is 4.85 m, and its student designers hope that it can travel fully submerged through water at 0.440 m/s. The water is freshwater (a lake) at T = 15 °C. The design team builds a one-fifth scale model to test in their university's wind tunnel, as shown in the Fig. A shield surrounds the drag balance strut so that the aerodynamic drag of the strut itself does not influence the measured drag. The air in the wind tunnel is at 25 °C and at one standard atmosphere pressure. At what air speed do they need to run the wind tunnel in order to achieve similarity? Take for water at T = 15 °C and atmospheric pressure, p = 999.1 kg/m³ and µ = 1.138 × 10-³ Pa.s. Take for air at T = 25 °C and atmospheric pressure, p = 1.184 kg/m³ and µ = 1.849 × 105 Pa.s. Wind tunnel test section V Poo, P Model Shield FD Drag balance Strut
Buckingham Pi. A mechanical stirrer is used to mix chemicals in a large tank. The required shaft power P is a function of liquid density p, viscosity μ, stirrer blade diameter D, and angular speed w of the spinning blades. (a) use repeating variables p, D, u to find a relation between dimensionless power (1) and w (m2); (b,c) a small 1/3 scale model is used in water to predict the actual required power in a viscous liquid with SG =2 and μ = 12μwater. Find (b) the ratio of speeds, wwater/ wactual, necessary for dynamic similarity and then (c) the predicted ratio of powers Pwater/ Pactual. expecting unit : (a) π1 ~ D ; π^2 ~ D^2; (b) wwater/ wactual: 10^0; (c) Pwater/ Pactual 10^-3 SI constant Patm = 10^5 Pa; pwater - 1000 kg/m^3; pair ~ 1.2kg/m^3; µwater ~ 10^-3 N•s/m^2; pair - 2 x 10^-5 N•s/m^2 ; g = 9.8 m/s^2 =

Recommended textbooks for you

Elements Of Electromagnetics

Mechanical Engineering

ISBN:

9780190698614

Author:

Sadiku, Matthew N. O.

Publisher:

Oxford University Press

Mechanics of Materials (10th Edition)

Mechanical Engineering

ISBN:

9780134319650

Author:

Russell C. Hibbeler

Publisher:

PEARSON

Thermodynamics: An Engineering Approach

Mechanical Engineering

ISBN:

9781259822674

Author:

Yunus A. Cengel Dr., Michael A. Boles

Publisher:

McGraw-Hill Education

Elements Of Electromagnetics

Mechanical Engineering

ISBN:

9780190698614

Author:

Sadiku, Matthew N. O.

Publisher:

Oxford University Press

Mechanics of Materials (10th Edition)

Mechanical Engineering

ISBN:

9780134319650

Author:

Russell C. Hibbeler

Publisher:

PEARSON

Thermodynamics: An Engineering Approach

Mechanical Engineering

ISBN:

9781259822674

Author:

Yunus A. Cengel Dr., Michael A. Boles

Publisher:

McGraw-Hill Education

Control Systems Engineering

Mechanical Engineering

ISBN:

9781118170519

Author:

Norman S. Nise

Publisher:

WILEY

Mechanics of Materials (MindTap Course List)

Mechanical Engineering

ISBN:

9781337093347

Author:

Barry J. Goodno, James M. Gere

Publisher:

Cengage Learning

Engineering Mechanics: Statics

Mechanical Engineering

ISBN:

9781118807330

Author:

James L. Meriam, L. G. Kraige, J. N. Bolton

Publisher:

WILEY

SEE MORE TEXTBOOKS