The depth in the soil of the Earth at which freezing temperatures penetrate is often of importance in agriculture and construction. During a certain fall day, the temperature in the Earth is constant at 15.6 oC to a depth of several meters. A cold wave suddenly reduces the air temperature from 15.6 oC to -17.8 oC. The convective coefficient above the soil is 11.36 W/m2 K. The soil properties are a = 4.65 x 10-7 m2/s and k = 0.865 W/m K. Neglect any latent heat effects. a) What is the surface temperature after 5.0 hours? b) To what depth in the soil will the freezing temperature of 0 °C penetrate in 5.0 hours?

The depth in the soil of the Earth at which freezing temperatures penetrate is often of importance in agriculture and construction. During a certain fall day, the temperature in the Earth is constant at 15.6 oC to a depth of several meters. A cold wave suddenly reduces the air temperature from 15.6 oC to -17.8 oC. The convective coefficient above the soil is 11.36 W/m2 K. The soil properties are a = 4.65 x 10-7 m2/s and k = 0.865 W/m K. Neglect any latent heat effects. a) What is the surface temperature after 5.0 hours? b) To what depth in the soil will the freezing temperature of 0 °C penetrate in 5.0 hours?

Fundamentals of Geotechnical Engineering (MindTap Course List)

5th Edition

ISBN:9781305635180

Author:Braja M. Das, Nagaratnam Sivakugan

Publisher:Braja M. Das, Nagaratnam Sivakugan

Chapter7: Seepage

Section: Chapter Questions

Problem 7.1P

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