In the design and development competition in a University, a team of students has planned to develop a prototype submarine with 6.5 meter length that would travel fully submerged at X m/s speed in a fresh lake water. The team has designed a model which has one-sixth of a prototype size to test in the university wind tunnel to study the effect of various parameters, such as drag force on the prototype (Figure Q2). Considering the necessary assumptions (a) determine the speed of the wind the team has to blow into the tunnel in order to achieve similarity. (b) With all the same conditions the team change their mind and want to develop a smaller size of model to save money and time. Targeting the maximum acceptable speed of the air blown not to exceed 125 m/s to avoid compressibility of air, what should be the minimum length of the model? (c) What will happen to the length of the model if the temperature of the blowing wind increases as a result of the season change? Discuss the reason.

In the design and development competition in a University, a team of students has planned to develop a prototype submarine with 6.5 meter length that would travel fully submerged at X m/s speed in a fresh lake water. The team has designed a model which has one-sixth of a prototype size to test in the university wind tunnel to study the effect of various parameters, such as drag force on the prototype (Figure Q2). Considering the necessary assumptions (a) determine the speed of the wind the team has to blow into the tunnel in order to achieve similarity. (b) With all the same conditions the team change their mind and want to develop a smaller size of model to save money and time. Targeting the maximum acceptable speed of the air blown not to exceed 125 m/s to avoid compressibility of air, what should be the minimum length of the model? (c) What will happen to the length of the model if the temperature of the blowing wind increases as a result of the season change? Discuss the reason.

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

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