An open tank, 6 mm in diameter, contains 1 mm deep layer of benzene (Mol wt = 78) at its bottom. The vapour pressure of benzene in the tank is 13.15 kN/m2 and its diffusion takes place through a stagnant air film 2.5 mm thick, At the operating temperature of 20°C, the diffusivity of benzene in the tank is 8.0 x 10-6 m2/s. If the benzene has a density of 880 kg/m³, calculate the time taken for the entire benzene to evaporate. Take atmospheric pressure as 101.3 kN/m² and neglect any resistance to diffusion of benzene beyond the air film. %3D

An open tank, 6 mm in diameter, contains 1 mm deep layer of benzene (Mol wt = 78) at its bottom. The vapour pressure of benzene in the tank is 13.15 kN/m2 and its diffusion takes place through a stagnant air film 2.5 mm thick, At the operating temperature of 20°C, the diffusivity of benzene in the tank is 8.0 x 10-6 m2/s. If the benzene has a density of 880 kg/m³, calculate the time taken for the entire benzene to evaporate. Take atmospheric pressure as 101.3 kN/m² and neglect any resistance to diffusion of benzene beyond the air film. %3D

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.

Chapter9: Heat Transfer With Phase Change

Section: Chapter Questions

Problem 9.29P

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