falls to earth at terminal velocity. Assume a hail ball (ice) falls into a warm layer of air at 1000 m (about 3000 ft) above the ground. The initial temperature of the hail on entering the warm layer is uniform at -20C and the surrounding air is at 5C and atmospheric pressure. The hail is at terminal velocity (assume the drag coefficient is 0.5). The diameter of the hail is 2 mm. (a) What is the terminal velocity of the hail? (If you can't get this, assume a value of 7 m/s for remaining parts. (small value question) (b) How far does the hail fall before surface of the hail begins to melt (i.e. surface reaches 0C)? (c) What is the temperature at the center of ice at this time? (d) Once the ice starts melting, assume the surface temperature stays at OC and determine how far the hail falls before enough energy is transferred to convert all of the ice to water. You can use a latent heat value for conversion of ice to water of 3.34e5 j/kg. You can use the same value of h that you calculated for the previous questions. answers(a: 6.2 m/s, b: 28 m, c: 272.9 K, d: 585 m)

falls to earth at terminal velocity. Assume a hail ball (ice) falls into a warm layer of air at 1000 m (about 3000 ft) above the ground. The initial temperature of the hail on entering the warm layer is uniform at -20C and the surrounding air is at 5C and atmospheric pressure. The hail is at terminal velocity (assume the drag coefficient is 0.5). The diameter of the hail is 2 mm. (a) What is the terminal velocity of the hail? (If you can't get this, assume a value of 7 m/s for remaining parts. (small value question) (b) How far does the hail fall before surface of the hail begins to melt (i.e. surface reaches 0C)? (c) What is the temperature at the center of ice at this time? (d) Once the ice starts melting, assume the surface temperature stays at OC and determine how far the hail falls before enough energy is transferred to convert all of the ice to water. You can use a latent heat value for conversion of ice to water of 3.34e5 j/kg. You can use the same value of h that you calculated for the previous questions. answers(a: 6.2 m/s, b: 28 m, c: 272.9 K, d: 585 m)

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 5.57P

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