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A defrost heater is integrated with the sun roof glass in order to prevent ice from forming. The sun roof begins at L1 = 0.3 m from the front of the roof and extends to L2 = 0.6 m. The roof is W = 1.2 m wide. The car is driving at u[infinity] = 10 m/s through air at T[infinity] = -15°C. Assume that the properties of the air are conductivity k = 0.023 W/m-K, density  = 1.3 kg/m3 , viscosity  = 1.65x10-5 Pa-s, and specific heat capacity c = 1003 J/kg-K. The defrost heater is a thin sheet of electrically resistive material that covers the entire sun roof and transfers a uniform heat flux to the glass. The convection coefficient between the interior surface of the roof and the cabin air is sufficiently low that convection heat transfer with the interior can be neglected. Assume that the flow over the roof remains laminar. Do not use a correlation to solve this problem; instead, use your conceptual knowledge of boundary layer behavior to estimate the answers

User Sdfor
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1 Answer

7 votes

Answer:

a) 119.75 w

b) 14.9⁰C

Step-by-step explanation:

See attached Image

A defrost heater is integrated with the sun roof glass in order to prevent ice from-example-1
User Norbert Radyk
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