An electric windshield defroster is used to remove 0.25-in of ice from a windshield. The properties of the ice are Tsat = 328F, uif = hif = 144 Btu/lbm, and v = 0.01602 ft3/lbm. Determine the electrical energy required per square foot of windshield surface area to melt this ice and remove it as liquid water at 328F. What is the minimum temperature at which the defroster may be operated? Assume that no heat is transferred from the defroster or ice to the surroundings.

An electric windshield defroster is used to remove 0.25-in of ice from a windshield. The properties of the ice are Tsat = 328F, uif = hif = 144 Btu/lbm, and v = 0.01602 ft3/lbm. Determine the electrical energy required per square foot of windshield surface area to melt this ice and remove it as liquid water at 328F. What is the minimum temperature at which the defroster may be operated? Assume that no heat is transferred from the defroster or ice to the surroundings.

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter44: Geothermal Heat Pumps

Section: Chapter Questions

Problem 1RQ: Geothermal heat pumps, or water-source heat pumps, are classified as either _____loop or _____loop...

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