Problem 01 t* = 0.015s 100 m In 1940, fluid dynamicist G. I. Taylor determined from Dimensional Analysis that the radius R of a fireball created by a nuclear explosion is exclusively determined by the released energy E, initial gas density po and elapsed time t* since detonation. Note: 1 kiloton = 4 × 1012 J (Joules). (a) List in a table the primary dimensions of R, E, po and t*. How many primary dimensions are there? (b) Find the single Pi group that controls the blast radius R. (c) In 1945, an experiment was conducted in the desert of New Mexico with a 20 kiloton bomb. On that day, air density was recorded at po = 1.23kg/m³. The photograph above taken at t* 0.015s shows a radius R108 m. Compute the value of the Pi group you have found. (d) Assuming that the Pi group remains constant, find the blast radius R at t* = 0.02s.

Problem 01 t* = 0.015s 100 m In 1940, fluid dynamicist G. I. Taylor determined from Dimensional Analysis that the radius R of a fireball created by a nuclear explosion is exclusively determined by the released energy E, initial gas density po and elapsed time t* since detonation. Note: 1 kiloton = 4 × 1012 J (Joules). (a) List in a table the primary dimensions of R, E, po and t. How many primary dimensions are there? (b) Find the single Pi group that controls the blast radius R. (c) In 1945, an experiment was conducted in the desert of New Mexico with a 20 kiloton bomb. On that day, air density was recorded at po = 1.23kg/m³. The photograph above taken at t 0.015s shows a radius R108 m. Compute the value of the Pi group you have found. (d) Assuming that the Pi group remains constant, find the blast radius R at t* = 0.02s.

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 5.9P: When a sphere falls freely through a homogeneous fluid, it reaches a terminal velocity at which the...

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