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

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

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

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using pure water at 20°C. The velocity of the prototype in seawater (p = A 1/18 scale model of the submarine is to be tested in the water tunnel 1015 kg/m³, v = 1.4x106 m²/s) is 3 m/s. Determine: a) the speed of the water in the water tunnel for dynamic similarity D) the ratio of the drag force on the model to the drag force on the prototype
(b) A wind-tunnel experiment is performed on a small 1:5 linear-scale model of a car, in order to assess the drag force F on a new full-size car design. A dimensionless "drag coefficient" Ca is defined by C, =- pu'A where A is the maximum cross-sectional area of the car in the flow. With the model car, a force of 3 N was recorded at a flow velocity u of 6 m s. Assuming that flow conditions are comparable (i.e., at the same Reynolds number), calculate the expected drag force for the full-sized car when the flow velocity past it is 31 m s (equivalent to 70 miles per hour). [The density of air p= 1.2 kg m.]
A prototype automobile is designed for cold weather inDenver, CO ( - 10 ° C, 83 kPa). Its drag force is tobe tested on a one-seventh-scale model in a wind tunnelat 150 mi/h, 20 ° C, and 1 atm. If the model and prototypeare to satisfy dynamic similarity, what prototypevelocity, in mi/h, needs to be matched? Comment onyour result.
(c) If a drag force of 214 N is measured o wind tunnel, a 1:20 scale model is created and tested at the same air temperature in order to determine the drag. A blimp typically flies at 20 m/s in air at standard conditions. In order to model the blimp's behavior in a LOAD (a) What is the AMO At a model velocity of 75 m/s, what is the appropriate air pressure in the wind tunnel? DO dimensionless parameter to use so that dynamic similarity is maintained? DO prototype be? CHE CHEGO EXAM yOT UPL OT on the model, what would the corresponding drag on the UPZ EXAM EXAM NOT U 20 NOT TO CHEC DAD
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