Air Ta = 0°C D Is Ясоnd A liquid water droplet of diameter D = 255 µm falls on a cold surface with temperature T, = -3°C. During phase change the droplet maintains a constant temperature Ta = 0°C. If the latent heat of fusion hsf = 334 for water, how much time tf does it take the droplet to freeze? Assume the drop does not deform and the only heat transfer is by conduction. The air has thermal conductivity k = 0.024 W %3D kg m-K Hint: The restrictions for Case 1 in Table 4.1 should really read z > D/2. The implication is that the droplet center can't be less than a radius away otherwise the droplet shape would deform away from spherical and the shape factor would no longer be valid. tf = 8 (3 sig figs)

Air Ta = 0°C D Is Ясоnd A liquid water droplet of diameter D = 255 µm falls on a cold surface with temperature T, = -3°C. During phase change the droplet maintains a constant temperature Ta = 0°C. If the latent heat of fusion hsf = 334 for water, how much time tf does it take the droplet to freeze? Assume the drop does not deform and the only heat transfer is by conduction. The air has thermal conductivity k = 0.024 W %3D kg m-K Hint: The restrictions for Case 1 in Table 4.1 should really read z > D/2. The implication is that the droplet center can't be less than a radius away otherwise the droplet shape would deform away from spherical and the shape factor would no longer be valid. tf = 8 (3 sig figs)

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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